Release 2.20.1

Allows to view the number of known UUIDs as
well as name to UUID pairs.

.github/ISSUE_TEMPLATE/config.yml

@@ -7,14 +7,11 @@ contact_links:
     url: https://github.com/EssentialsX/Essentials/discussions/categories/q-a
     about: Visit the Q&A forum to search for previous help requests.
   - name: Check past feature suggestions
-    url: https://github.com/EssentialsX/Essentials/discussions/categories/ideas-and-feature-suggestions
+    url: https://github.com/EssentialsX/Essentials/issues?q=is%3Aissue+label%3A%22type%3A+enhancement%22
     about: Visit the Feature Suggestions forum to view and discuss existing feature suggestions.
   - name: Create help request
     url: https://github.com/EssentialsX/Essentials/discussions/new?category=q-a
     about: Create a support ticket to get help from developers.
-  - name: Suggest a feature
-    url: https://github.com/EssentialsX/Essentials/discussions/new?category=ideas-and-feature-suggestions
-    about: Suggest new features for EssentialsX!
   - name: Get help from the community on Discord
     url: https://discord.gg/casfFyh
     about: Join the MOSS Discord for community-powered EssentialsX support!

.github/ISSUE_TEMPLATE/request-a-feature.yml

@@ -0,0 +1,40 @@
+name: Request a feature
+description: Suggest a feature you want to see in EssentialsX!
+labels: 'type: enhancement'
+body:
+- type: markdown
+  attributes:
+    value: |
+      If you have a feature suggestion for EssentialsX, read the following tips:
+      1.  Fill out the template.
+            This will help us understand what you're requesting and why you want us
+            to add it.
+      2.  Keep it simple.
+            Make sure it's easy to understand what you're requesting. A good way is
+            to keep it to one request per GitHub issue, as we can then easily track
+            feature requests.
+      3.  Check whether it has already been asked or added.
+            You can search the issue tracker to see if your feature has already been
+            requested at https://github.com/EssentialsX/Essentials/issues. You can
+            also check the changelogs to see if the feature was recently added:
+            https://github.com/EssentialsX/Essentials/releases
+      4.  Ask yourself: "Does this belong in EssentialsX?"
+            There are lots of features that we reject because most servers won't
+            need or use them. If your feature is very specific or already exists in
+            another plugin, it might not be a good fit for EssentialsX.
+- type: textarea
+  attributes:
+    label: Feature description
+    description: Explain what you should expect to happen.
+    placeholder: |
+      What feature are you suggesting?
+  validations:
+    required: true
+- type: textarea
+  attributes:
+    label: How the feature is useful
+    description: Explain what actually happens.
+    placeholder: |
+      How is the feature useful to players, server owners and/or developers?
+  validations:
+    required: true

.github/workflows/build-master.yml

@@ -5,6 +5,9 @@ on:
     branches:
     - 2.x
     - dev/*
+  release:
+    types:
+    - published
 
 jobs:
   build:
@@ -13,26 +16,18 @@ jobs:
 
     steps:
     - name: Checkout Git repo
-      uses: actions/checkout@v2
+      uses: actions/checkout@v3
       with:
         fetch-depth: 0
 
-    - name: Restore Gradle cache
-      uses: actions/cache@v2
+    - name: Set up JDK 17
+      uses: actions/setup-java@v3
       with:
-        path: ~/.gradle/caches
-        key: ${{ runner.os }}-gradle-${{ hashFiles('**/*.gradle*') }}
-        restore-keys: |
-          ${{ runner.os }}-gradle-
+        distribution: 'temurin'
+        java-version: 17
 
-    - name: Set up JDK 16
-      uses: actions/setup-java@v2
-      with:
-        distribution: 'adopt'
-        java-version: 16
-
-    - name: Validate Gradle Wrapper
-      uses: gradle/wrapper-validation-action@v1
+    - name: Setup Gradle
+      uses: gradle/gradle-build-action@v2
 
     - name: Build with Gradle
       run: |
@@ -40,7 +35,7 @@ jobs:
         ./gradlew build --stacktrace
 
     - name: Archive plugin jars on GitHub
-      uses: actions/upload-artifact@master
+      uses: actions/upload-artifact@v3
       with:
         name: EssentialsX plugin jars
         path: jars/
@@ -54,22 +49,43 @@ jobs:
         ./gradlew publish
 
     - name: Prepare Javadocs
-      if: ${{ success() && github.event_name == 'push' && github.repository == 'EssentialsX/Essentials' && github.ref == 'refs/heads/2.x' }}
       run: |
         mv Essentials/build/docs/javadoc/ javadocs/
         cp -r EssentialsAntiBuild/build/docs/javadoc/ javadocs/EssentialsAntiBuild/
         cp -r EssentialsChat/build/docs/javadoc/ javadocs/EssentialsChat/
         cp -r EssentialsDiscord/build/docs/javadoc/ javadocs/EssentialsDiscord/
+        cp -r EssentialsDiscordLink/build/docs/javadoc/ javadocs/EssentialsDiscordLink/
         cp -r EssentialsGeoIP/build/docs/javadoc/ javadocs/EssentialsGeoIP/
         cp -r EssentialsProtect/build/docs/javadoc/ javadocs/EssentialsProtect/
         cp -r EssentialsSpawn/build/docs/javadoc/ javadocs/EssentialsSpawn/
         cp -r EssentialsXMPP/build/docs/javadoc/ javadocs/EssentialsXMPP/
 
-    - name: Deploy Javadocs
-      if: ${{ success() && github.event_name == 'push' && github.repository == 'EssentialsX/Essentials' && github.ref == 'refs/heads/2.x' }}
-      uses: netlify/actions/cli@master
+    - name: Archive Javadocs
+      uses: actions/upload-artifact@v3
       with:
-        args: deploy --dir=javadocs/ --prod --message="GitHubActionsDeploy"
+        name: javadocs
+        path: javadocs/
+
+  publish-jd:
+    name: Publish Javadocs
+    needs: build
+    if: ${{ github.event_name == 'push' && github.repository == 'EssentialsX/Essentials' && github.ref == 'refs/heads/2.x' }}
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: Setup Node
+      uses: actions/setup-node@v3
+      with:
+        node-version: 16
+
+    - name: Download Javadocs
+      uses: actions/download-artifact@v3
+      with:
+        name: javadocs
+        path: javadocs/
+
+    - name: Deploy Javadocs
+      run: npx netlify-cli deploy --dir=javadocs/ --prod --message="GitHubActionsDeploy"
       env:
         NETLIFY_AUTH_TOKEN: ${{ secrets.NETLIFY_JD_AUTH_TOKEN }}
         NETLIFY_SITE_ID: ${{ secrets.NETLIFY_JD_2X_SITE_ID }}

.github/workflows/build-pr.yml

@@ -18,26 +18,18 @@ jobs:
 
     steps:
     - name: Checkout Git repo
-      uses: actions/checkout@v2
+      uses: actions/checkout@v3
       with:
         fetch-depth: 0
 
-    - name: Restore Gradle cache
-      uses: actions/cache@v2
+    - name: Set up JDK 17
+      uses: actions/setup-java@v3
       with:
-        path: ~/.gradle/caches
-        key: ${{ runner.os }}-gradle-${{ hashFiles('**/*.gradle*') }}
-        restore-keys: |
-          ${{ runner.os }}-gradle-
+        distribution: 'temurin'
+        java-version: 17
 
-    - name: Set up JDK 16
-      uses: actions/setup-java@v2
-      with:
-        distribution: 'adopt'
-        java-version: 16
-
-    - name: Validate Gradle Wrapper
-      uses: gradle/wrapper-validation-action@v1
+    - name: Setup Gradle
+      uses: gradle/gradle-build-action@v2
 
     - name: Build with Gradle
       run: |
@@ -45,7 +37,7 @@ jobs:
         ./gradlew build --stacktrace
 
     - name: Archive plugin jars on GitHub
-      uses: actions/upload-artifact@master
+      uses: actions/upload-artifact@v3
       with:
         name: EssentialsX plugin jars
         path: jars/

.gitignore

@@ -15,6 +15,8 @@
 /Essentials/kits.yml
 /Essentials/userdata/testplayer1.yml
 /Essentials/usermap.csv
+/Essentials/usermap.bin
+/Essentials/uuids.bin
 
 # Build files
 .gradle/

.idea/checkstyle-idea.xml

@@ -1,19 +1,27 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
-  <component name="CheckStyle-IDEA">
-    <option name="configuration">
-      <map>
-        <entry key="active-configuration" value="PROJECT_RELATIVE:$PROJECT_DIR$/.checkstyle/checkstyle.xml:EssentialsX" />
-        <entry key="checkstyle-version" value="8.36.2" />
-        <entry key="copy-libs" value="true" />
-        <entry key="location-0" value="BUNDLED:(bundled):Sun Checks" />
-        <entry key="location-1" value="BUNDLED:(bundled):Google Checks" />
-        <entry key="location-2" value="PROJECT_RELATIVE:$PROJECT_DIR$/.checkstyle/checkstyle.xml:EssentialsX" />
-        <entry key="property-2.configDirectory" value=".checkstyle/" />
-        <entry key="scan-before-checkin" value="true" />
-        <entry key="scanscope" value="JavaOnly" />
-        <entry key="suppress-errors" value="false" />
-      </map>
+  <component name="CheckStyle-IDEA" serialisationVersion="2">
+    <checkstyleVersion>8.36.2</checkstyleVersion>
+    <scanScope>JavaOnly</scanScope>
+    <copyLibs>true</copyLibs>
+    <scanBeforeCheckin>true</scanBeforeCheckin>
+    <option name="thirdPartyClasspath" />
+    <option name="activeLocationIds">
+      <option value="321e5753-4201-4d2c-bf31-6232011122fd" />
+    </option>
+    <option name="locations">
+      <list>
+        <ConfigurationLocation id="bundled-sun-checks" type="BUNDLED" scope="All" description="Sun Checks">(bundled)</ConfigurationLocation>
+        <ConfigurationLocation id="bundled-google-checks" type="BUNDLED" scope="All" description="Google Checks">(bundled)</ConfigurationLocation>
+        <ConfigurationLocation id="321e5753-4201-4d2c-bf31-6232011122fd" type="PROJECT_RELATIVE" scope="All" description="EssentialsX">
+          $PROJECT_DIR$/.checkstyle/checkstyle.xml
+          <option name="properties">
+            <map>
+              <entry key="configDirectory" value=".checkstyle/" />
+            </map>
+          </option>
+        </ConfigurationLocation>
+      </list>
     </option>
   </component>
 </project>

Essentials/build.gradle

@@ -29,6 +29,10 @@ dependencies {
     }
 }
 
+test {
+    testLogging.showStandardStreams = true
+}
+
 shadowJar {
     dependencies {
         include (dependency('io.papermc:paperlib'))

Essentials/src/main/java/com/earth2me/essentials/Backup.java

@@ -102,12 +102,12 @@ public class Backup implements Runnable {
                             } while (line != null);
                         }
                     } catch (final IOException ex) {
-                        ess.getLogger().log(Level.SEVERE, null, ex);
+                        ess.getLogger().log(Level.SEVERE, "An error occurred while reading backup child process", ex);
                     }
                 });
                 child.waitFor();
             } catch (final InterruptedException | IOException ex) {
-                ess.getLogger().log(Level.SEVERE, null, ex);
+                ess.getLogger().log(Level.SEVERE, "An error occurred while building the backup child process", ex);
             } finally {
                 class BackupEnableSaveTask implements Runnable {
                     @Override

Essentials/src/main/java/com/earth2me/essentials/BalanceTopImpl.java

@@ -28,8 +28,8 @@ public class BalanceTopImpl implements BalanceTop {
     private void calculateBalanceTopMap() {
         final List<Entry> entries = new LinkedList<>();
         BigDecimal newTotal = BigDecimal.ZERO;
-        for (UUID u : ess.getUserMap().getAllUniqueUsers()) {
-            final User user = ess.getUserMap().getUser(u);
+        for (UUID u : ess.getUsers().getAllUserUUIDs()) {
+            final User user = ess.getUsers().loadUncachedUser(u);
             if (user != null) {
                 if (!ess.getSettings().isNpcsInBalanceRanking() && user.isNPC()) {
                     // Don't list NPCs in output
@@ -40,7 +40,7 @@ public class BalanceTopImpl implements BalanceTop {
                     user.updateMoneyCache(userMoney);
                     newTotal = newTotal.add(userMoney);
                     final String name;
-                    if (user.getBase() instanceof OfflinePlayer) {
+                    if (user.getBase() instanceof OfflinePlayerStub) {
                         name = user.getLastAccountName();
                     } else if (user.isHidden()) {
                         name = user.getName();

Essentials/src/main/java/com/earth2me/essentials/Essentials.java

@@ -39,6 +39,7 @@ import com.earth2me.essentials.textreader.IText;
 import com.earth2me.essentials.textreader.KeywordReplacer;
 import com.earth2me.essentials.textreader.SimpleTextInput;
 import com.earth2me.essentials.updatecheck.UpdateChecker;
+import com.earth2me.essentials.userstorage.ModernUserMap;
 import com.earth2me.essentials.utils.FormatUtil;
 import com.earth2me.essentials.utils.VersionUtil;
 import io.papermc.lib.PaperLib;
@@ -143,7 +144,7 @@ import static com.earth2me.essentials.I18n.tl;
 public class Essentials extends JavaPlugin implements net.ess3.api.IEssentials {
     private static final Logger BUKKIT_LOGGER = Logger.getLogger("Essentials");
     private static Logger LOGGER = null;
-    private final transient TNTExplodeListener tntListener = new TNTExplodeListener(this);
+    private final transient TNTExplodeListener tntListener = new TNTExplodeListener();
     private final transient Set<String> vanishedPlayers = new LinkedHashSet<>();
     private transient ISettings settings;
     private transient Jails jails;
@@ -155,7 +156,9 @@ public class Essentials extends JavaPlugin implements net.ess3.api.IEssentials {
     private transient CustomItemResolver customItemResolver;
     private transient PermissionsHandler permissionsHandler;
     private transient AlternativeCommandsHandler alternativeCommandsHandler;
-    private transient UserMap userMap;
+    @Deprecated
+    private transient UserMap legacyUserMap;
+    private transient ModernUserMap userMap;
     private transient BalanceTopImpl balanceTop;
     private transient ExecuteTimer execTimer;
     private transient MailService mail;
@@ -222,7 +225,7 @@ public class Essentials extends JavaPlugin implements net.ess3.api.IEssentials {
         LOGGER.log(Level.INFO, dataFolder.toString());
         settings = new Settings(this);
         mail = new MailServiceImpl(this);
-        userMap = new UserMap(this);
+        userMap = new ModernUserMap(this);
         balanceTop = new BalanceTopImpl(this);
         permissionsHandler = new PermissionsHandler(this, false);
         Economy.setEss(this);
@@ -301,11 +304,14 @@ public class Essentials extends JavaPlugin implements net.ess3.api.IEssentials {
             confList.add(settings);
             execTimer.mark("Settings");
 
+            upgrade.preModules();
+            execTimer.mark("Upgrade2");
+
             mail = new MailServiceImpl(this);
             execTimer.mark("Init(Mail)");
 
-            userMap = new UserMap(this);
-            confList.add(userMap);
+            userMap = new ModernUserMap(this);
+            legacyUserMap = new UserMap(userMap);
             execTimer.mark("Init(Usermap)");
 
             balanceTop = new BalanceTopImpl(this);
@@ -317,7 +323,7 @@ public class Essentials extends JavaPlugin implements net.ess3.api.IEssentials {
             execTimer.mark("Kits");
 
             upgrade.afterSettings();
-            execTimer.mark("Upgrade2");
+            execTimer.mark("Upgrade3");
 
             warps = new Warps(this.getDataFolder());
             confList.add(warps);
@@ -588,7 +594,7 @@ public class Essentials extends JavaPlugin implements net.ess3.api.IEssentials {
 
         Economy.setEss(null);
         Trade.closeLog();
-        getUserMap().getUUIDMap().shutdown();
+        getUsers().shutdown();
 
         HandlerList.unregisterAll(this);
     }
@@ -948,17 +954,7 @@ public class Essentials extends JavaPlugin implements net.ess3.api.IEssentials {
     //This will return null if there is not a match.
     @Override
     public User getOfflineUser(final String name) {
-        final User user = userMap.getUser(name);
-        if (user != null && user.getBase() instanceof OfflinePlayer) {
-            //This code should attempt to use the last known name of a user, if Bukkit returns name as null.
-            final String lastName = user.getLastAccountName();
-            if (lastName != null) {
-                ((OfflinePlayer) user.getBase()).setName(lastName);
-            } else {
-                ((OfflinePlayer) user.getBase()).setName(name);
-            }
-        }
-        return user;
+        return userMap.getUser(name);
     }
 
     @Override
@@ -1046,7 +1042,7 @@ public class Essentials extends JavaPlugin implements net.ess3.api.IEssentials {
             return true;
         }
 
-        return interactor.getBase().canSee(interactee.getBase());
+        return !interactee.isHiddenFrom(interactor.getBase());
     }
 
     //This will create a new user if there is not a match.
@@ -1061,14 +1057,9 @@ public class Essentials extends JavaPlugin implements net.ess3.api.IEssentials {
             return null;
         }
 
-        User user = userMap.getUser(base.getUniqueId());
+        final User user = userMap.getUser(base);
 
-        if (user == null) {
-            if (getSettings().isDebug()) {
-                LOGGER.log(Level.INFO, "Constructing new userfile from base player " + base.getName());
-            }
-            user = new User(base, this);
-        } else {
+        if (base.getClass() != UUIDPlayer.class || user.getBase() == null) {
             user.update(base);
         }
         return user;
@@ -1182,11 +1173,6 @@ public class Essentials extends JavaPlugin implements net.ess3.api.IEssentials {
         return this.getScheduler().scheduleSyncRepeatingTask(this, run, delay, period);
     }
 
-    @Override
-    public TNTExplodeListener getTNTListener() {
-        return tntListener;
-    }
-
     @Override
     public PermissionsHandler getPermissionsHandler() {
         return permissionsHandler;
@@ -1203,7 +1189,13 @@ public class Essentials extends JavaPlugin implements net.ess3.api.IEssentials {
     }
 
     @Override
+    @Deprecated
     public UserMap getUserMap() {
+        return legacyUserMap;
+    }
+
+    @Override
+    public ModernUserMap getUsers() {
         return userMap;
     }
 

Essentials/src/main/java/com/earth2me/essentials/EssentialsBlockListener.java

@@ -1,5 +1,6 @@
 package com.earth2me.essentials;
 
+import com.earth2me.essentials.craftbukkit.Inventories;
 import com.earth2me.essentials.utils.MaterialUtil;
 import net.ess3.api.IEssentials;
 import org.bukkit.GameMode;
@@ -45,7 +46,7 @@ public class EssentialsBlockListener implements Listener {
                 if (is != null && is.getType() != null && !MaterialUtil.isAir(is.getType())) {
                     final ItemStack cloneIs = is.clone();
                     cloneIs.setAmount(1);
-                    user.getBase().getInventory().addItem(cloneIs);
+                    Inventories.addItem(user.getBase(), cloneIs);
                     user.getBase().updateInventory();
                 }
             });

Essentials/src/main/java/com/earth2me/essentials/EssentialsEntityListener.java

@@ -1,6 +1,6 @@
 package com.earth2me.essentials;
 
-import com.earth2me.essentials.utils.MaterialUtil;
+import com.earth2me.essentials.craftbukkit.Inventories;
 import com.earth2me.essentials.utils.VersionUtil;
 import net.ess3.api.IEssentials;
 import org.bukkit.Location;
@@ -52,12 +52,12 @@ public class EssentialsEntityListener implements Listener {
             if (eDefend instanceof Player) {
                 onPlayerVsPlayerDamage(event, (Player) eDefend, attacker);
             } else if (eDefend instanceof Ageable) {
-                final ItemStack hand = attacker.getBase().getItemInHand();
+                final ItemStack hand = Inventories.getItemInMainHand(attacker.getBase());
                 if (ess.getSettings().isMilkBucketEasterEggEnabled()
                     && hand != null && hand.getType() == Material.MILK_BUCKET) {
                     ((Ageable) eDefend).setBaby();
                     hand.setType(Material.BUCKET);
-                    attacker.getBase().setItemInHand(hand);
+                    Inventories.setItemInMainHand(attacker.getBase(), hand);
                     attacker.getBase().updateInventory();
                     event.setCancelled(true);
                 }
@@ -98,7 +98,7 @@ public class EssentialsEntityListener implements Listener {
     }
 
     private void onPlayerVsPlayerPowertool(final EntityDamageByEntityEvent event, final Player defender, final User attacker) {
-        final List<String> commandList = attacker.getPowertool(attacker.getBase().getItemInHand());
+        final List<String> commandList = attacker.getPowertool(Inventories.getItemInHand(attacker.getBase()));
         if (commandList != null && !commandList.isEmpty()) {
             for (final String tempCommand : commandList) {
                 final String command = powertoolPlayer.matcher(tempCommand).replaceAll(defender.getName());
@@ -196,73 +196,23 @@ public class EssentialsEntityListener implements Listener {
             final ISettings.KeepInvPolicy vanish = ess.getSettings().getVanishingItemsPolicy();
             final ISettings.KeepInvPolicy bind = ess.getSettings().getBindingItemsPolicy();
             if (VersionUtil.getServerBukkitVersion().isHigherThanOrEqualTo(VersionUtil.v1_11_2_R01) && (vanish != ISettings.KeepInvPolicy.KEEP || bind != ISettings.KeepInvPolicy.KEEP)) {
-                for (final ItemStack stack : event.getEntity().getInventory()) {
-                    if (stack != null && !MaterialUtil.isAir(stack.getType())) {
-                        if (stack.getEnchantments().containsKey(Enchantment.VANISHING_CURSE)) {
-                            if (vanish == ISettings.KeepInvPolicy.DELETE) {
-                                event.getEntity().getInventory().remove(stack);
-                            } else if (vanish == ISettings.KeepInvPolicy.DROP) {
-                                event.getDrops().add(stack);
-                                event.getEntity().getInventory().remove(stack);
-                            }
-                        }
-                        if (stack.getEnchantments().containsKey(Enchantment.BINDING_CURSE)) {
-                            if (bind == ISettings.KeepInvPolicy.DELETE) {
-                                event.getEntity().getInventory().remove(stack);
-                            } else if (bind == ISettings.KeepInvPolicy.DROP) {
-                                event.getEntity().getInventory().remove(stack);
-                                event.getDrops().add(stack);
-                            }
+                Inventories.removeItems(user.getBase(), stack -> {
+                    if (vanish != ISettings.KeepInvPolicy.KEEP && stack.getEnchantments().containsKey(Enchantment.VANISHING_CURSE)) {
+                        if (vanish == ISettings.KeepInvPolicy.DROP) {
+                            event.getDrops().add(stack.clone());
                         }
+                        return true;
                     }
-                }
 
-                // Now check armor
-                final ItemStack[] armor = event.getEntity().getInventory().getArmorContents();
-                for (int i = 0; i < armor.length; i++) {
-                    final ItemStack stack = armor[i];
-                    if (stack != null && !MaterialUtil.isAir(stack.getType())) {
-                        if (stack.getEnchantments().containsKey(Enchantment.VANISHING_CURSE)) {
-                            if (vanish == ISettings.KeepInvPolicy.DELETE) {
-                                armor[i] = null;
-                            } else if (vanish == ISettings.KeepInvPolicy.DROP) {
-                                if (!event.getDrops().contains(stack)) {
-                                    event.getDrops().add(stack);
-                                }
-                                armor[i] = null;
-                            }
-                        }
-                        if (stack.getEnchantments().containsKey(Enchantment.BINDING_CURSE)) {
-                            if (bind == ISettings.KeepInvPolicy.DELETE) {
-                                armor[i] = null;
-                            } else if (bind == ISettings.KeepInvPolicy.DROP) {
-                                if (!event.getDrops().contains(stack)) {
-                                    event.getDrops().add(stack);
-                                }
-                                armor[i] = null;
-                            }
+                    if (bind != ISettings.KeepInvPolicy.KEEP && stack.getEnchantments().containsKey(Enchantment.BINDING_CURSE)) {
+                        if (bind == ISettings.KeepInvPolicy.DROP) {
+                            event.getDrops().add(stack.clone());
                         }
+                        return true;
                     }
-                }
-                event.getEntity().getInventory().setArmorContents(armor);
 
-                // Now check offhand
-                if (VersionUtil.getServerBukkitVersion().isHigherThanOrEqualTo(VersionUtil.v1_9_R01)) {
-                    final ItemStack stack = event.getEntity().getInventory().getItemInOffHand();
-                    //noinspection ConstantConditions
-                    if (stack != null && !MaterialUtil.isAir(stack.getType())) {
-                        final boolean isVanish = stack.getEnchantments().containsKey(Enchantment.VANISHING_CURSE);
-                        final boolean isBind = stack.getEnchantments().containsKey(Enchantment.BINDING_CURSE);
-                        if (isVanish || isBind) {
-                            event.getEntity().getInventory().setItemInOffHand(null);
-                            if ((isVanish && vanish == ISettings.KeepInvPolicy.DROP) || (isBind && bind == ISettings.KeepInvPolicy.DROP)) {
-                                if (!event.getDrops().contains(stack)) {
-                                    event.getDrops().add(stack);
-                                }
-                            }
-                        }
-                    }
-                }
+                    return false;
+                }, true);
             }
         }
     }

Essentials/src/main/java/com/earth2me/essentials/EssentialsPlayerListener.java

@@ -1,6 +1,7 @@
 package com.earth2me.essentials;
 
 import com.earth2me.essentials.commands.Commandfireball;
+import com.earth2me.essentials.craftbukkit.Inventories;
 import com.earth2me.essentials.textreader.IText;
 import com.earth2me.essentials.textreader.KeywordReplacer;
 import com.earth2me.essentials.textreader.TextInput;
@@ -120,6 +121,15 @@ public class EssentialsPlayerListener implements Listener, FakeAccessor {
         }
     }
 
+    private static boolean isGameEventEvent() {
+        try {
+            Class.forName("org.bukkit.event.block.BlockReceiveGameEvent");
+            return true;
+        } catch (final ClassNotFoundException ignored) {
+            return false;
+        }
+    }
+
     public void registerEvents() {
         ess.getServer().getPluginManager().registerEvents(this, ess);
 
@@ -127,6 +137,10 @@ public class EssentialsPlayerListener implements Listener, FakeAccessor {
             ess.getServer().getPluginManager().registerEvents(new ArrowPickupListener(), ess);
         }
 
+        if (isGameEventEvent()) {
+            ess.getServer().getPluginManager().registerEvents(new SculkListener1_17(), ess);
+        }
+
         if (isEntityPickupEvent()) {
             ess.getServer().getPluginManager().registerEvents(new PickupListener1_12(), ess);
         } else {
@@ -192,17 +206,26 @@ public class EssentialsPlayerListener implements Listener, FakeAccessor {
             return;
         }
 
-        if (!ess.getSettings().cancelAfkOnMove() && !ess.getSettings().getFreezeAfkPlayers()) {
-            event.getHandlers().unregister(this);
+        final User user = ess.getUser(event.getPlayer());
 
-            if (ess.getSettings().isDebug()) {
-                ess.getLogger().log(Level.INFO, "Unregistering move listener");
+        if (user.isFreeze()) {
+            final Location from = event.getFrom();
+            final Location to = event.getTo().clone();
+            to.setX(from.getX());
+            to.setY(from.getY());
+            to.setZ(from.getZ());
+            try {
+                event.setTo(LocationUtil.getSafeDestination(ess, to));
+            } catch (final Exception ex) {
+                event.setTo(to);
             }
-
             return;
         }
 
-        final User user = ess.getUser(event.getPlayer());
+        if (!ess.getSettings().cancelAfkOnMove() && !ess.getSettings().getFreezeAfkPlayers()) {
+            return;
+        }
+
         if (user.isAfk() && ess.getSettings().getFreezeAfkPlayers()) {
             final Location from = event.getFrom();
             final Location origTo = event.getTo();
@@ -308,6 +331,7 @@ public class EssentialsPlayerListener implements Listener, FakeAccessor {
 
         ess.getBackup().onPlayerJoin();
         final User dUser = ess.getUser(player);
+        dUser.update(player);
 
         dUser.startTransaction();
         if (dUser.isNPC()) {
@@ -367,7 +391,7 @@ public class EssentialsPlayerListener implements Listener, FakeAccessor {
                 } else if (ess.getSettings().isCustomJoinMessage()) {
                     final String msg = (newUsername ? ess.getSettings().getCustomNewUsernameMessage() : ess.getSettings().getCustomJoinMessage())
                         .replace("{PLAYER}", player.getDisplayName()).replace("{USERNAME}", player.getName())
-                        .replace("{UNIQUE}", NumberFormat.getInstance().format(ess.getUserMap().getUniqueUsers()))
+                        .replace("{UNIQUE}", NumberFormat.getInstance().format(ess.getUsers().getUserCount()))
                         .replace("{ONLINE}", NumberFormat.getInstance().format(ess.getOnlinePlayers().size()))
                         .replace("{UPTIME}", DateUtil.formatDateDiff(ManagementFactory.getRuntimeMXBean().getStartTime()))
                         .replace("{PREFIX}", FormatUtil.replaceFormat(ess.getPermissionsHandler().getPrefix(player)))
@@ -527,6 +551,7 @@ public class EssentialsPlayerListener implements Listener, FakeAccessor {
     public void onPlayerLogin(final PlayerLoginEvent event) {
         if (event.getResult() == Result.KICK_FULL) {
             final User kfuser = ess.getUser(event.getPlayer());
+            kfuser.update(event.getPlayer());
             if (kfuser.isAuthorized("essentials.joinfullserver")) {
                 event.allow();
                 return;
@@ -557,7 +582,7 @@ public class EssentialsPlayerListener implements Listener, FakeAccessor {
         final User user = ess.getUser(event.getPlayer());
         final ItemStack stack = new ItemStack(Material.EGG, 1);
         if (user.hasUnlimited(stack)) {
-            user.getBase().getInventory().addItem(stack);
+            Inventories.addItem(user.getBase(), stack);
             user.getBase().updateInventory();
         }
     }
@@ -650,7 +675,8 @@ public class EssentialsPlayerListener implements Listener, FakeAccessor {
         }
 
         if (ess.getSettings().isCommandCooldownsEnabled()
-            && !user.isAuthorized("essentials.commandcooldowns.bypass")) {
+            && !user.isAuthorized("essentials.commandcooldowns.bypass")
+            && (pluginCommand == null || !user.isAuthorized("essentials.commandcooldowns.bypass." + pluginCommand.getName()))) {
             final int argStartIndex = effectiveCommand.indexOf(" ");
             final String args = argStartIndex == -1 ? "" // No arguments present
                 : " " + effectiveCommand.substring(argStartIndex); // arguments start at argStartIndex; substring from there.
@@ -988,6 +1014,15 @@ public class EssentialsPlayerListener implements Listener, FakeAccessor {
         }
     }
 
+    private final class SculkListener1_17 implements Listener {
+        @EventHandler
+        public void onGameEvent(final org.bukkit.event.block.BlockReceiveGameEvent event) {
+            if (event.getEntity() instanceof Player && ess.getUser((Player) event.getEntity()).isVanished()) {
+                event.setCancelled(true);
+            }
+        }
+    }
+
     private final class CommandSendFilter implements CommandSendListenerProvider.Filter {
         @Override
         public Predicate<String> apply(Player player) {

Essentials/src/main/java/com/earth2me/essentials/EssentialsUpgrade.java

@@ -4,9 +4,9 @@ import com.earth2me.essentials.config.ConfigurateUtil;
 import com.earth2me.essentials.config.EssentialsConfiguration;
 import com.earth2me.essentials.config.EssentialsUserConfiguration;
 import com.earth2me.essentials.craftbukkit.BanLookup;
+import com.earth2me.essentials.userstorage.ModernUUIDCache;
 import com.earth2me.essentials.utils.StringUtil;
 import com.google.common.base.Charsets;
-import com.google.common.collect.Maps;
 import com.google.common.io.Files;
 import com.google.gson.reflect.TypeToken;
 import net.ess3.api.IEssentials;
@@ -31,10 +31,10 @@ import java.math.BigDecimal;
 import java.math.BigInteger;
 import java.security.DigestInputStream;
 import java.security.MessageDigest;
-import java.text.DecimalFormat;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.Date;
+import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Locale;
@@ -47,13 +47,12 @@ import java.util.concurrent.ScheduledFuture;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.logging.Level;
-import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
 import static com.earth2me.essentials.I18n.tl;
 
 public class EssentialsUpgrade {
-    private static final FileFilter YML_FILTER = pathname -> pathname.isFile() && pathname.getName().endsWith(".yml");
+    public static final FileFilter YML_FILTER = pathname -> pathname.isFile() && pathname.getName().endsWith(".yml");
     private static final String PATTERN_CONFIG_UUID_REGEX = "(?mi)^uuid:\\s*([0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12})\\s*$";
     private static final Pattern PATTERN_CONFIG_UUID = Pattern.compile(PATTERN_CONFIG_UUID_REGEX);
     private static final String PATTERN_CONFIG_NAME_REGEX = "(?mi)^lastAccountName:\\s*[\"\']?(\\w+)[\"\']?\\s*$";
@@ -93,7 +92,6 @@ public class EssentialsUpgrade {
             final int showProgress = countFiles % 250;
 
             if (showProgress == 0) {
-                ess.getUserMap().getUUIDMap().forceWriteUUIDMap();
                 ess.getLogger().info("Converted " + countFiles + "/" + userdir.list().length);
             }
 
@@ -103,7 +101,8 @@ public class EssentialsUpgrade {
             final EssentialsUserConfiguration config;
             UUID uuid = null;
             try {
-                uuid = UUID.fromString(name);
+                //noinspection ResultOfMethodCallIgnored
+                UUID.fromString(name);
             } catch (final IllegalArgumentException ex) {
                 final File file = new File(userdir, string);
                 final EssentialsConfiguration conf = new EssentialsConfiguration(file);
@@ -115,6 +114,7 @@ public class EssentialsUpgrade {
 
                 final String uuidString = conf.getString(uuidConf, null);
 
+                //noinspection ConstantConditions
                 for (int i = 0; i < 4; i++) {
                     try {
                         uuid = UUID.fromString(uuidString);
@@ -122,7 +122,7 @@ public class EssentialsUpgrade {
                         break;
                     } catch (final Exception ex2) {
                         if (conf.getBoolean("npc", false)) {
-                            uuid = UUID.nameUUIDFromBytes(("NPC:" + name).getBytes(Charsets.UTF_8));
+                            uuid = UUID.nameUUIDFromBytes(("NPC:" + (ess.getSettings().isSafeUsermap() ? StringUtil.safeString(name) : name)).getBytes(Charsets.UTF_8));
                             break;
                         }
 
@@ -130,23 +130,24 @@ public class EssentialsUpgrade {
                         uuid = player.getUniqueId();
                     }
 
+                    //noinspection ConstantConditions
                     if (uuid != null) {
                         countBukkit++;
                         break;
                     }
                 }
 
+                //noinspection ConstantConditions
                 if (uuid != null) {
                     conf.blockingSave();
                     config = new EssentialsUserConfiguration(name, uuid, new File(userdir, uuid + ".yml"));
                     config.convertLegacyFile();
-                    ess.getUserMap().trackUUID(uuid, name, false);
+                    ess.getUsers().loadUncachedUser(uuid);
                     continue;
                 }
                 countFails++;
             }
         }
-        ess.getUserMap().getUUIDMap().forceWriteUUIDMap();
 
         ess.getLogger().info("Converted " + countFiles + "/" + countFiles + ".  Conversion complete.");
         ess.getLogger().info("Converted via cache: " + countEssCache + " :: Converted via lookup: " + countBukkit + " :: Failed to convert: " + countFails);
@@ -913,74 +914,76 @@ public class EssentialsUpgrade {
         Bukkit.getBanList(BanList.Type.NAME).addBan(playerName, banReason, banTimeout == 0 ? null : new Date(banTimeout), Console.NAME);
     }
 
-    private void repairUserMap() {
-        if (doneFile.getBoolean("userMapRepaired", false)) {
+    public void generateUidCache() {
+        if (doneFile.getBoolean("newUidCacheBuilt", false)) {
             return;
         }
-        ess.getLogger().info("Starting usermap repair");
 
+        final File usermapFile = new File(ess.getDataFolder(), "usermap.bin");
+        final File uidsFile = new File(ess.getDataFolder(), "uuids.bin");
         final File userdataFolder = new File(ess.getDataFolder(), "userdata");
-        if (!userdataFolder.isDirectory()) {
+
+        if (!userdataFolder.isDirectory() || usermapFile.exists() || uidsFile.exists()) {
             ess.getLogger().warning("Missing userdata folder, aborting");
+            doneFile.setProperty("newUidCacheBuilt", true);
+            doneFile.save();
             return;
         }
-        final File[] files = userdataFolder.listFiles(YML_FILTER);
 
-        final DecimalFormat format = new DecimalFormat("#0.00");
-        final Map<String, UUID> names = Maps.newHashMap();
-
-        for (int index = 0; index < files.length; index++) {
-            final File file = files[index];
-            try {
-                UUID uuid = null;
-                final String filename = file.getName();
-                final String configData = new String(java.nio.file.Files.readAllBytes(file.toPath()), Charsets.UTF_8);
-
-                if (filename.length() > 36) {
-                    try {
-                        // ".yml" ending has 4 chars...
-                        uuid = UUID.fromString(filename.substring(0, filename.length() - 4));
-                    } catch (final IllegalArgumentException ignored) {
-                    }
-                }
-
-                final Matcher uuidMatcher = PATTERN_CONFIG_UUID.matcher(configData);
-                if (uuidMatcher.find()) {
-                    try {
-                        uuid = UUID.fromString(uuidMatcher.group(1));
-                    } catch (final IllegalArgumentException ignored) {
-                    }
-                }
-
-                if (uuid == null) {
-                    // Don't import
-                    continue;
-                }
-
-                final Matcher nameMatcher = PATTERN_CONFIG_NAME.matcher(configData);
-                if (nameMatcher.find()) {
-                    final String username = nameMatcher.group(1);
-                    if (username != null && username.length() > 0) {
-                        names.put(StringUtil.safeString(username), uuid);
-                    }
-                }
-
-                if (index % 1000 == 0) {
-                    ess.getLogger().info("Reading: " + format.format((100d * (double) index) / files.length)
-                        + "%");
-                }
-            } catch (final IOException e) {
-                ess.getLogger().log(Level.SEVERE, "Error while reading file: ", e);
+        try {
+            if (!usermapFile.createNewFile() || !uidsFile.createNewFile()) {
+                ess.getLogger().warning("Couldn't create usermap.bin or uuids.bin, aborting");
                 return;
             }
+
+            final Map<UUID, Long> uuids = new HashMap<>();
+            final Map<String, UUID> nameToUuidMap = new HashMap<>();
+
+            final File[] files = userdataFolder.listFiles(YML_FILTER);
+            if (files != null) {
+                for (final File file : files) {
+                    try {
+                        final String fileName = file.getName();
+                        final UUID uuid = UUID.fromString(fileName.substring(0, fileName.length() - 4));
+                        final EssentialsConfiguration config = new EssentialsConfiguration(file);
+                        config.load();
+                        String name = config.getString("last-account-name", null);
+                        name = ess.getSettings().isSafeUsermap() ? StringUtil.safeString(name) : name;
+                        final long time = config.getLong("timestamps.logout", 0L);
+
+                        if (name != null) {
+                            if (nameToUuidMap.containsKey(name)) {
+                                final UUID oldUuid = nameToUuidMap.get(name);
+                                if (oldUuid.version() < uuid.version() || (oldUuid.version() == uuid.version() && uuids.get(oldUuid) < time)) {
+                                    ess.getLogger().warning("New UUID found for " + name + ": " + uuid + " (old: " + oldUuid + "). Replacing.");
+                                    uuids.remove(oldUuid);
+                                } else {
+                                    ess.getLogger().warning("Found UUID for " + name + ": " + uuid + " (old: " + oldUuid + "). Skipping.");
+                                    continue;
+                                }
+                            }
+
+                            uuids.put(uuid, time);
+                            nameToUuidMap.put(name, uuid);
+                        }
+                    } catch (IllegalArgumentException | IndexOutOfBoundsException ignored) {
+                    }
+                }
+            }
+
+            if (!nameToUuidMap.isEmpty()) {
+                ModernUUIDCache.writeNameUuidMap(usermapFile, nameToUuidMap);
+            }
+
+            if (!uuids.isEmpty()) {
+                ModernUUIDCache.writeUuidCache(uidsFile, uuids.keySet());
+            }
+
+            doneFile.setProperty("newUidCacheBuilt", true);
+            doneFile.save();
+        } catch (final IOException e) {
+            ess.getLogger().log(Level.SEVERE, "Error while generating initial uuids/names cache", e);
         }
-
-        ess.getUserMap().getNames().putAll(names);
-        ess.getUserMap().reloadConfig();
-
-        doneFile.setProperty("userMapRepaired", true);
-        doneFile.save();
-        ess.getLogger().info("Completed usermap repair.");
     }
 
     public void beforeSettings() {
@@ -991,6 +994,10 @@ public class EssentialsUpgrade {
         moveMotdRulesToFile("rules");
     }
 
+    public void preModules() {
+        generateUidCache();
+    }
+
     public void afterSettings() {
         sanitizeAllUserFilenames();
         updateUsersPowerToolsFormat();
@@ -1001,7 +1008,6 @@ public class EssentialsUpgrade {
         uuidFileChange();
         banFormatChange();
         warnMetrics();
-        repairUserMap();
         convertIgnoreList();
         convertStupidCamelCaseUserdataKeys();
         convertMailList();

Essentials/src/main/java/com/earth2me/essentials/IEssentials.java

@@ -7,6 +7,7 @@ import com.earth2me.essentials.commands.IEssentialsCommand;
 import com.earth2me.essentials.commands.PlayerNotFoundException;
 import com.earth2me.essentials.perm.PermissionsHandler;
 import com.earth2me.essentials.updatecheck.UpdateChecker;
+import com.earth2me.essentials.userstorage.IUserMap;
 import net.ess3.nms.refl.providers.ReflOnlineModeProvider;
 import net.ess3.provider.ContainerProvider;
 import net.ess3.provider.FormattedCommandAliasProvider;
@@ -109,8 +110,6 @@ public interface IEssentials extends Plugin {
 
     int scheduleSyncRepeatingTask(Runnable run, long delay, long period);
 
-    TNTExplodeListener getTNTListener();
-
     PermissionsHandler getPermissionsHandler();
 
     AlternativeCommandsHandler getAlternativeCommandsHandler();
@@ -119,6 +118,9 @@ public interface IEssentials extends Plugin {
 
     IItemDb getItemDb();
 
+    IUserMap getUsers();
+
+    @Deprecated
     UserMap getUserMap();
 
     BalanceTop getBalanceTop();

Essentials/src/main/java/com/earth2me/essentials/ISettings.java

@@ -282,6 +282,8 @@ public interface ISettings extends IConf {
 
     int getMaxUserCacheCount();
 
+    long getMaxUserCacheValueExpiry();
+
     boolean allowSilentJoinQuit();
 
     boolean isCustomJoinMessage();

Essentials/src/main/java/com/earth2me/essentials/IUser.java

@@ -155,6 +155,8 @@ public interface IUser {
 
     void delHome(String name) throws Exception;
 
+    void renameHome(String name, String newName) throws Exception;
+
     boolean hasHome();
 
     Location getLastLocation();
@@ -330,4 +332,12 @@ public interface IUser {
             this.time = time;
         }
     }
+
+    List<String> getPastUsernames();
+
+    void addPastUsername(String username);
+
+    boolean isFreeze();
+
+    void setFreeze(boolean freeze);
 }

Essentials/src/main/java/com/earth2me/essentials/Jails.java

@@ -203,6 +203,10 @@ public class Jails implements net.ess3.api.IJails {
     private class JailListener implements Listener {
         @EventHandler(priority = EventPriority.LOW, ignoreCancelled = true)
         public void onJailBlockBreak(final BlockBreakEvent event) {
+            if (shouldIgnore(event.getPlayer())) {
+                return;
+            }
+
             final User user = ess.getUser(event.getPlayer());
             if (user.isJailed() && !user.isAuthorized("essentials.jail.allow-break")) {
                 event.setCancelled(true);
@@ -211,6 +215,10 @@ public class Jails implements net.ess3.api.IJails {
 
         @EventHandler(priority = EventPriority.LOW, ignoreCancelled = true)
         public void onJailBlockPlace(final BlockPlaceEvent event) {
+            if (shouldIgnore(event.getPlayer())) {
+                return;
+            }
+
             final User user = ess.getUser(event.getPlayer());
             if (user.isJailed() && !user.isAuthorized("essentials.jail.allow-place")) {
                 event.setCancelled(true);
@@ -219,6 +227,10 @@ public class Jails implements net.ess3.api.IJails {
 
         @EventHandler(priority = EventPriority.LOW, ignoreCancelled = true)
         public void onJailBlockDamage(final BlockDamageEvent event) {
+            if (shouldIgnore(event.getPlayer())) {
+                return;
+            }
+
             final User user = ess.getUser(event.getPlayer());
             if (user.isJailed() && !user.isAuthorized("essentials.jail.allow-block-damage")) {
                 event.setCancelled(true);
@@ -232,6 +244,9 @@ public class Jails implements net.ess3.api.IJails {
             }
             final Entity damager = event.getDamager();
             if (damager.getType() == EntityType.PLAYER) {
+                if (shouldIgnore((Player) damager)) {
+                    return;
+                }
                 final User user = ess.getUser((Player) damager);
                 if (user != null && user.isJailed()) {
                     event.setCancelled(true);
@@ -241,6 +256,10 @@ public class Jails implements net.ess3.api.IJails {
 
         @EventHandler(priority = EventPriority.LOW, ignoreCancelled = true)
         public void onJailPlayerInteract(final PlayerInteractEvent event) {
+            if (shouldIgnore(event.getPlayer())) {
+                return;
+            }
+
             final User user = ess.getUser(event.getPlayer());
             if (user.isJailed() && !user.isAuthorized("essentials.jail.allow-interact")) {
                 event.setCancelled(true);
@@ -249,6 +268,10 @@ public class Jails implements net.ess3.api.IJails {
 
         @EventHandler(priority = EventPriority.LOW, ignoreCancelled = true)
         public void onJailPlayerGameModeChange(final PlayerGameModeChangeEvent event) {
+            if (shouldIgnore(event.getPlayer())) {
+                return;
+            }
+
             final User user = ess.getUser(event.getPlayer());
             if (user.isJailed()) {
                 event.setCancelled(true);
@@ -257,6 +280,10 @@ public class Jails implements net.ess3.api.IJails {
 
         @EventHandler(priority = EventPriority.HIGHEST)
         public void onJailPlayerRespawn(final PlayerRespawnEvent event) {
+            if (shouldIgnore(event.getPlayer())) {
+                return;
+            }
+
             final User user = ess.getUser(event.getPlayer());
             if (!user.isJailed() || user.getJail() == null || user.getJail().isEmpty()) {
                 return;
@@ -275,6 +302,10 @@ public class Jails implements net.ess3.api.IJails {
 
         @EventHandler(priority = EventPriority.HIGH)
         public void onJailPlayerTeleport(final PlayerTeleportEvent event) {
+            if (shouldIgnore(event.getPlayer())) {
+                return;
+            }
+
             final User user = ess.getUser(event.getPlayer());
             if (!user.isJailed() || user.getJail() == null || user.getJail().isEmpty()) {
                 return;
@@ -294,6 +325,10 @@ public class Jails implements net.ess3.api.IJails {
 
         @EventHandler(priority = EventPriority.HIGHEST)
         public void onJailPlayerJoin(final PlayerJoinEvent event) {
+            if (shouldIgnore(event.getPlayer())) {
+                return;
+            }
+
             final User user = ess.getUser(event.getPlayer());
             final long currentTime = System.currentTimeMillis();
             user.checkJailTimeout(currentTime);
@@ -318,5 +353,10 @@ public class Jails implements net.ess3.api.IJails {
                 future.completeExceptionally(ex);
             }
         }
+
+        private boolean shouldIgnore(final Player base) {
+            // Ignore Citizens NPCs
+            return base.getUniqueId().version() == 2 || base.hasMetadata("NPC");
+        }
     }
 }

Essentials/src/main/java/com/earth2me/essentials/Kit.java

@@ -2,23 +2,23 @@ package com.earth2me.essentials;
 
 import com.earth2me.essentials.Trade.OverflowType;
 import com.earth2me.essentials.commands.NoChargeException;
-import com.earth2me.essentials.craftbukkit.InventoryWorkaround;
+import com.earth2me.essentials.craftbukkit.Inventories;
 import com.earth2me.essentials.textreader.IText;
 import com.earth2me.essentials.textreader.KeywordReplacer;
 import com.earth2me.essentials.textreader.SimpleTextInput;
 import com.earth2me.essentials.utils.DateUtil;
-import com.earth2me.essentials.utils.MaterialUtil;
 import com.earth2me.essentials.utils.NumberUtil;
 import net.ess3.api.IEssentials;
 import net.ess3.api.events.KitClaimEvent;
+import net.essentialsx.api.v2.events.KitPreExpandItemsEvent;
 import org.bukkit.Bukkit;
 import org.bukkit.Material;
 import org.bukkit.inventory.ItemStack;
-import org.bukkit.inventory.PlayerInventory;
 import org.yaml.snakeyaml.external.biz.base64Coder.Base64Coder;
 
 import java.math.BigDecimal;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.Calendar;
 import java.util.GregorianCalendar;
 import java.util.List;
@@ -214,57 +214,38 @@ public class Kit {
                     stack = metaStack.getItemStack();
                 }
 
-                if (autoEquip) {
-                    final Material material = stack.getType();
-                    final PlayerInventory inventory = user.getBase().getInventory();
-                    if (MaterialUtil.isHelmet(material) && isEmptyStack(inventory.getHelmet())) {
-                        inventory.setHelmet(stack);
-                        continue;
-                    } else if (MaterialUtil.isChestplate(material) && isEmptyStack(inventory.getChestplate())) {
-                        inventory.setChestplate(stack);
-                        continue;
-                    } else if (MaterialUtil.isLeggings(material) && isEmptyStack(inventory.getLeggings())) {
-                        inventory.setLeggings(stack);
-                        continue;
-                    } else if (MaterialUtil.isBoots(material) && isEmptyStack(inventory.getBoots())) {
-                        inventory.setBoots(stack);
-                        continue;
-                    }
-                }
-
                 itemList.add(stack);
             }
 
-            final Map<Integer, ItemStack> overfilled;
-            final boolean allowOversizedStacks = user.isAuthorized("essentials.oversizedstacks");
+            final int maxStackSize = user.isAuthorized("essentials.oversizedstacks") ? ess.getSettings().getOversizedStackSize() : 0;
             final boolean isDropItemsIfFull = ess.getSettings().isDropItemsIfFull();
-            if (isDropItemsIfFull) {
-                if (allowOversizedStacks) {
-                    overfilled = InventoryWorkaround.addOversizedItems(user.getBase().getInventory(), ess.getSettings().getOversizedStackSize(), itemList.toArray(new ItemStack[0]));
-                } else {
-                    overfilled = InventoryWorkaround.addItems(user.getBase().getInventory(), itemList.toArray(new ItemStack[0]));
+
+            final KitPreExpandItemsEvent itemsEvent = new KitPreExpandItemsEvent(user, kitName, itemList);
+            Bukkit.getPluginManager().callEvent(itemsEvent);
+
+            final ItemStack[] itemArray = itemList.toArray(new ItemStack[0]);
+
+            if (!isDropItemsIfFull && !Inventories.hasSpace(user.getBase(), maxStackSize, autoEquip, itemArray)) {
+                user.sendMessage(tl("kitInvFullNoDrop"));
+                return false;
+            }
+
+            final Map<Integer, ItemStack> leftover = Inventories.addItem(user.getBase(), maxStackSize, autoEquip, itemArray);
+            if (!isDropItemsIfFull && !leftover.isEmpty()) {
+                // Inventories#hasSpace should prevent this state from EVER being reached; If it does, something has gone terribly wrong, and we should just give up and hope people report it :(
+                throw new IllegalStateException("Something has gone terribly wrong while adding items to the user's inventory. Please report this to the EssentialsX developers. Items left over: " + leftover + ". Original items: " + Arrays.toString(itemArray));
+            }
+
+            for (final ItemStack itemStack : leftover.values()) {
+                int spillAmount = itemStack.getAmount();
+                if (maxStackSize != 0) {
+                    itemStack.setAmount(Math.min(spillAmount, itemStack.getMaxStackSize()));
                 }
-                for (final ItemStack itemStack : overfilled.values()) {
-                    int spillAmount = itemStack.getAmount();
-                    if (!allowOversizedStacks) {
-                        itemStack.setAmount(Math.min(spillAmount, itemStack.getMaxStackSize()));
-                    }
-                    while (spillAmount > 0) {
-                        user.getWorld().dropItemNaturally(user.getLocation(), itemStack);
-                        spillAmount -= itemStack.getAmount();
-                    }
-                    spew = true;
-                }
-            } else {
-                if (allowOversizedStacks) {
-                    overfilled = InventoryWorkaround.addAllOversizedItems(user.getBase().getInventory(), ess.getSettings().getOversizedStackSize(), itemList.toArray(new ItemStack[0]));
-                } else {
-                    overfilled = InventoryWorkaround.addAllItems(user.getBase().getInventory(), itemList.toArray(new ItemStack[0]));
-                }
-                if (overfilled != null) {
-                    user.sendMessage(tl("kitInvFullNoDrop"));
-                    return false;
+                while (spillAmount > 0) {
+                    user.getWorld().dropItemNaturally(user.getLocation(), itemStack);
+                    spillAmount -= itemStack.getAmount();
                 }
+                spew = true;
             }
             user.getBase().updateInventory();
 
@@ -291,8 +272,4 @@ public class Kit {
         }
         return true;
     }
-
-    private boolean isEmptyStack(ItemStack stack) {
-        return stack == null || MaterialUtil.isAir(stack.getType());
-    }
 }

Essentials/src/main/java/com/earth2me/essentials/MailServiceImpl.java

@@ -1,9 +1,11 @@
 package com.earth2me.essentials;
 
 import net.ess3.api.IUser;
-import net.essentialsx.api.v2.services.mail.MailService;
+import net.essentialsx.api.v2.events.UserMailEvent;
 import net.essentialsx.api.v2.services.mail.MailMessage;
 import net.essentialsx.api.v2.services.mail.MailSender;
+import net.essentialsx.api.v2.services.mail.MailService;
+import org.bukkit.Bukkit;
 import org.bukkit.plugin.ServicePriority;
 
 import java.text.SimpleDateFormat;
@@ -35,6 +37,12 @@ public class MailServiceImpl implements MailService {
     }
 
     private void sendMail(IUser recipient, MailMessage message) {
+        final UserMailEvent event = new UserMailEvent(recipient, message);
+        Bukkit.getPluginManager().callEvent(event);
+        if (event.isCancelled()) {
+            return;
+        }
+
         final ArrayList<MailMessage> messages = recipient.getMailMessages();
         messages.add(0, message);
         recipient.setMailList(messages);

Essentials/src/main/java/com/earth2me/essentials/MetaItemStack.java

@@ -194,14 +194,14 @@ public class MetaItemStack {
         final Material WRITTEN_BOOK = EnumUtil.getMaterial("WRITTEN_BOOK");
 
         if (split.length > 1 && split[0].equalsIgnoreCase("name") && hasMetaPermission(sender, "name", false, true, ess)) {
-            final String displayName = FormatUtil.replaceFormat(split[1].replace('_', ' '));
+            final String displayName = FormatUtil.replaceFormat(split[1].replaceAll("(?<!\\\\)_", " ").replace("\\_", "_"));
             final ItemMeta meta = stack.getItemMeta();
             meta.setDisplayName(displayName);
             stack.setItemMeta(meta);
         } else if (split.length > 1 && (split[0].equalsIgnoreCase("lore") || split[0].equalsIgnoreCase("desc")) && hasMetaPermission(sender, "lore", false, true, ess)) {
             final List<String> lore = new ArrayList<>();
             for (final String line : split[1].split("(?<!\\\\)\\|")) {
-                lore.add(FormatUtil.replaceFormat(line.replace('_', ' ').replace("\\|", "|")));
+                lore.add(FormatUtil.replaceFormat(line.replaceAll("(?<!\\\\)_", " ").replace("\\_", "_").replace("\\|", "|")));
             }
             final ItemMeta meta = stack.getItemMeta();
             meta.setLore(lore);
@@ -230,7 +230,7 @@ public class MetaItemStack {
             meta.setAuthor(author);
             stack.setItemMeta(meta);
         } else if (split.length > 1 && split[0].equalsIgnoreCase("title") && stack.getType() == WRITTEN_BOOK && hasMetaPermission(sender, "title", false, true, ess)) {
-            final String title = FormatUtil.replaceFormat(split[1].replace('_', ' '));
+            final String title = FormatUtil.replaceFormat(split[1].replaceAll("(?<!\\\\)_", " ").replace("\\_", "_"));
             final BookMeta meta = (BookMeta) stack.getItemMeta();
             meta.setTitle(title);
             stack.setItemMeta(meta);
@@ -240,7 +240,7 @@ public class MetaItemStack {
             final List<String> pages = meta.hasPages() ? new ArrayList<>(meta.getPages()) : new ArrayList<>();
             final List<String> lines = new ArrayList<>();
             for (final String line : split[1].split("(?<!\\\\)\\|")) {
-                lines.add(FormatUtil.replaceFormat(line.replace('_', ' ').replace("\\|", "|")));
+                lines.add(FormatUtil.replaceFormat(line.replaceAll("(?<!\\\\)_", " ").replace("\\_", "_").replace("\\|", "|")));
             }
             final String content = String.join("\n", lines);
             if (page >= pages.size()) {

Essentials/src/main/java/com/earth2me/essentials/Mob.java

@@ -109,6 +109,8 @@ public enum Mob {
     TADPOLE("Tadpole", Enemies.FRIENDLY, "TADPOLE"),
     WARDEN("Warden", Enemies.ENEMY, "WARDEN"),
     CHEST_BOAT("ChestBoat", Enemies.NEUTRAL, "CHEST_BOAT"),
+    CAMEL("Camel", Enemies.FRIENDLY, "CAMEL"),
+    SNIFFER("Sniffer", Enemies.FRIENDLY, "SNIFFER"),
     ;
 
     private static final Map<String, Mob> hashMap = new HashMap<>();

Essentials/src/main/java/com/earth2me/essentials/MobCompat.java

@@ -3,9 +3,11 @@ package com.earth2me.essentials;
 import com.earth2me.essentials.utils.EnumUtil;
 import com.earth2me.essentials.utils.VersionUtil;
 import net.ess3.nms.refl.ReflUtil;
+import org.bukkit.Material;
 import org.bukkit.TreeSpecies;
 import org.bukkit.entity.Axolotl;
 import org.bukkit.entity.Boat;
+import org.bukkit.entity.Camel;
 import org.bukkit.entity.Entity;
 import org.bukkit.entity.EntityType;
 import org.bukkit.entity.Fox;
@@ -15,8 +17,10 @@ import org.bukkit.entity.MushroomCow;
 import org.bukkit.entity.Ocelot;
 import org.bukkit.entity.Panda;
 import org.bukkit.entity.Parrot;
+import org.bukkit.entity.Player;
 import org.bukkit.entity.TropicalFish;
 import org.bukkit.entity.Villager;
+import org.bukkit.inventory.ItemStack;
 
 import java.lang.reflect.Method;
 
@@ -41,6 +45,7 @@ public final class MobCompat {
     public static final EntityType AXOLOTL = getEntityType("AXOLOTL");
     public static final EntityType GOAT = getEntityType("GOAT");
     public static final EntityType FROG = getEntityType("FROG");
+    public static final EntityType CAMEL = getEntityType("CAMEL");
 
     // Constants for mobs that have changed since earlier versions
     public static final EntityType CAT = getEntityType("CAT", "OCELOT");
@@ -195,6 +200,19 @@ public final class MobCompat {
         }
     }
 
+    public static void setCamelSaddle(final Entity entity, final Player target) {
+        if (VersionUtil.getServerBukkitVersion().isLowerThan(VersionUtil.v1_20_1_R01)) {
+            return;
+        }
+
+        if (entity instanceof Camel) {
+            final Camel camel = (Camel) entity;
+            camel.setTamed(true);
+            camel.setOwner(target);
+            camel.getInventory().setSaddle(new ItemStack(Material.SADDLE, 1));
+        }
+    }
+
     public enum CatType {
         // These are (loosely) Mojang names for the cats
         SIAMESE("SIAMESE", "SIAMESE_CAT"),

Essentials/src/main/java/com/earth2me/essentials/MobData.java

@@ -1,6 +1,6 @@
 package com.earth2me.essentials;
 
-import com.earth2me.essentials.craftbukkit.InventoryWorkaround;
+import com.earth2me.essentials.craftbukkit.Inventories;
 import com.earth2me.essentials.utils.EnumUtil;
 import com.earth2me.essentials.utils.StringUtil;
 import com.earth2me.essentials.utils.VersionUtil;
@@ -209,6 +209,7 @@ public enum MobData {
     MANGROVE_BOAT("mangrove", Boat.class, MobCompat.BoatVariant.MANGROVE, true),
     OAK_BOAT("oak", Boat.class, MobCompat.BoatVariant.OAK, true),
     SPRUCE_BOAT("spruce", Boat.class, MobCompat.BoatVariant.SPRUCE, true),
+    SADDLE_CAMEL("saddle", MobCompat.CAMEL, Data.CAMELSADDLE, true),
     ;
 
     final private String nickname;
@@ -362,8 +363,8 @@ public enum MobData {
                 ((Horse) spawned).getInventory().setArmor(new ItemStack((Material) this.value, 1));
             } else if (this.type.equals(EntityType.ZOMBIE.getEntityClass()) || this.type.equals(EntityType.SKELETON)) {
                 final EntityEquipment invent = ((LivingEntity) spawned).getEquipment();
-                InventoryWorkaround.setItemInMainHand(invent, new ItemStack((Material) this.value, 1));
-                InventoryWorkaround.setItemInMainHandDropChance(invent, 0.1f);
+                Inventories.setItemInMainHand(invent, new ItemStack((Material) this.value, 1));
+                Inventories.setItemInMainHandDropChance(invent, 0.1f);
             }
         } else if (this.value.equals(Data.RAID_LEADER)) {
             ((Raider) spawned).setPatrolLeader(true);
@@ -387,6 +388,8 @@ public enum MobData {
             }
         } else if (this.value.equals(Data.GOAT_SCREAMING)) {
             ((Goat) spawned).setScreaming(true);
+        } else if (this.value.equals(Data.CAMELSADDLE)) {
+            MobCompat.setCamelSaddle(spawned, target);
         } else if (this.value instanceof MobCompat.BoatVariant) {
             MobCompat.setBoatVariant(spawned, (MobCompat.BoatVariant) this.value);
         } else if (this.value instanceof String) {
@@ -446,5 +449,6 @@ public enum MobData {
         FISH_BODY_COLOR,
         FISH_PATTERN_COLOR,
         GOAT_SCREAMING,
+        CAMELSADDLE,
     }
 }

Essentials/src/main/java/com/earth2me/essentials/PlayerList.java

@@ -55,9 +55,9 @@ public final class PlayerList {
         int playerHidden = 0;
         int hiddenCount = 0;
         for (final User onlinePlayer : ess.getOnlineUsers()) {
-            if (onlinePlayer.isHidden() || (user != null && !user.getBase().canSee(onlinePlayer.getBase()))) {
+            if (onlinePlayer.isHidden() || (user != null && onlinePlayer.isHiddenFrom(user.getBase()))) {
                 playerHidden++;
-                if (showHidden || user != null && user.getBase().canSee(onlinePlayer.getBase())) {
+                if (showHidden || user != null && !onlinePlayer.isHiddenFrom(user.getBase())) {
                     hiddenCount++;
                 }
             }
@@ -75,7 +75,7 @@ public final class PlayerList {
     public static Map<String, List<User>> getPlayerLists(final IEssentials ess, final IUser sender, final boolean showHidden) {
         final Map<String, List<User>> playerList = new HashMap<>();
         for (final User onlineUser : ess.getOnlineUsers()) {
-            if ((sender == null && !showHidden && onlineUser.isHidden()) || (sender != null && !showHidden && !sender.getBase().canSee(onlineUser.getBase()))) {
+            if ((sender == null && !showHidden && onlineUser.isHidden()) || (sender != null && !showHidden && onlineUser.isHiddenFrom(sender.getBase()))) {
                 continue;
             }
             final String group = FormatUtil.stripFormat(FormatUtil.stripEssentialsFormat(onlineUser.getGroup().toLowerCase()));

Essentials/src/main/java/com/earth2me/essentials/PlayerTarget.java

@@ -4,15 +4,17 @@ import org.bukkit.Bukkit;
 import org.bukkit.Location;
 import org.bukkit.entity.Player;
 
+import java.util.UUID;
+
 public class PlayerTarget implements ITarget {
-    private final String name;
+    private final UUID uuid;
 
     public PlayerTarget(final Player entity) {
-        this.name = entity.getName();
+        this.uuid = entity.getUniqueId();
     }
 
     @Override
     public Location getLocation() {
-        return Bukkit.getServer().getPlayerExact(name).getLocation();
+        return Bukkit.getPlayer(uuid).getLocation();
     }
 }

Essentials/src/main/java/com/earth2me/essentials/Settings.java

@@ -1469,10 +1469,16 @@ public class Settings implements net.ess3.api.ISettings {
     // #easteregg
     @Override
     public int getMaxUserCacheCount() {
-        final long count = Runtime.getRuntime().maxMemory() / 1024 / 96;
+        final long count = Runtime.getRuntime().maxMemory() / 1024 / 1024;
         return config.getInt("max-user-cache-count", (int) count);
     }
 
+    // #easteregg
+    @Override
+    public long getMaxUserCacheValueExpiry() {
+        return config.getLong("max-user-cache-value-expiry", 600);
+    }
+
     @Override
     public boolean isLastMessageReplyRecipient() {
         return config.getBoolean("last-message-reply-recipient", false);

Essentials/src/main/java/com/earth2me/essentials/SpawnMob.java

@@ -1,7 +1,7 @@
 package com.earth2me.essentials;
 
 import com.earth2me.essentials.Mob.MobException;
-import com.earth2me.essentials.craftbukkit.InventoryWorkaround;
+import com.earth2me.essentials.craftbukkit.Inventories;
 import com.earth2me.essentials.utils.EnumUtil;
 import com.earth2me.essentials.utils.LocationUtil;
 import com.earth2me.essentials.utils.StringUtil;
@@ -251,8 +251,8 @@ public final class SpawnMob {
     private static void defaultMobData(final EntityType type, final Entity spawned) {
         if (type == EntityType.SKELETON) {
             final EntityEquipment invent = ((LivingEntity) spawned).getEquipment();
-            InventoryWorkaround.setItemInMainHand(invent, new ItemStack(Material.BOW, 1));
-            InventoryWorkaround.setItemInMainHandDropChance(invent, 0.1f);
+            Inventories.setItemInMainHand(invent, new ItemStack(Material.BOW, 1));
+            Inventories.setItemInMainHandDropChance(invent, 0.1f);
         }
 
         if (type == MobCompat.ZOMBIFIED_PIGLIN) {
@@ -260,8 +260,8 @@ public final class SpawnMob {
             setVillager(zombie, false);
 
             final EntityEquipment invent = zombie.getEquipment();
-            InventoryWorkaround.setItemInMainHand(invent, new ItemStack(GOLDEN_SWORD, 1));
-            InventoryWorkaround.setItemInMainHandDropChance(invent, 0.1f);
+            Inventories.setItemInMainHand(invent, new ItemStack(GOLDEN_SWORD, 1));
+            Inventories.setItemInMainHandDropChance(invent, 0.1f);
         }
 
         if (type == EntityType.ZOMBIE) {

Essentials/src/main/java/com/earth2me/essentials/TNTExplodeListener.java

@@ -1,51 +1,22 @@
 package com.earth2me.essentials;
 
-import net.ess3.api.IEssentials;
-import org.bukkit.entity.LivingEntity;
+import com.earth2me.essentials.commands.Commandnuke;
+import org.bukkit.entity.TNTPrimed;
 import org.bukkit.event.EventHandler;
 import org.bukkit.event.EventPriority;
 import org.bukkit.event.Listener;
 import org.bukkit.event.entity.EntityExplodeEvent;
 
-public class TNTExplodeListener implements Listener, Runnable {
-    private final transient IEssentials ess;
-    private transient boolean enabled = false;
-    private transient int timer = -1;
-
-    public TNTExplodeListener(final IEssentials ess) {
-        super();
-        this.ess = ess;
-    }
-
-    public void enable() {
-        if (!enabled) {
-            enabled = true;
-            timer = ess.scheduleSyncDelayedTask(this, 200);
-            return;
-        }
-        if (timer != -1) {
-            ess.getScheduler().cancelTask(timer);
-            timer = ess.scheduleSyncDelayedTask(this, 200);
-        }
-    }
-
+public class TNTExplodeListener implements Listener {
     @EventHandler(priority = EventPriority.LOW)
     public void onEntityExplode(final EntityExplodeEvent event) {
-        if (!enabled) {
+        if (!(event.getEntity() instanceof TNTPrimed)) {
             return;
         }
-        if (event.getEntity() instanceof LivingEntity) {
-            return;
-        }
-        if (event.blockList().size() < 1) {
+        if (!event.getEntity().hasMetadata(Commandnuke.NUKE_META_KEY)) {
             return;
         }
         event.setCancelled(true);
         event.getLocation().getWorld().createExplosion(event.getLocation(), 0F);
     }
-
-    @Override
-    public void run() {
-        enabled = false;
-    }
 }

Essentials/src/main/java/com/earth2me/essentials/Trade.java

@@ -1,6 +1,6 @@
 package com.earth2me.essentials;
 
-import com.earth2me.essentials.craftbukkit.InventoryWorkaround;
+import com.earth2me.essentials.craftbukkit.Inventories;
 import com.earth2me.essentials.craftbukkit.SetExpFix;
 import com.earth2me.essentials.utils.NumberUtil;
 import com.earth2me.essentials.utils.VersionUtil;
@@ -8,7 +8,6 @@ import net.ess3.api.IEssentials;
 import net.ess3.api.IUser;
 import net.ess3.api.MaxMoneyException;
 import org.bukkit.Location;
-import org.bukkit.entity.Item;
 import org.bukkit.inventory.ItemStack;
 
 import java.io.File;
@@ -16,6 +15,7 @@ import java.io.FileWriter;
 import java.io.IOException;
 import java.math.BigDecimal;
 import java.text.DateFormat;
+import java.util.Collections;
 import java.util.Date;
 import java.util.Locale;
 import java.util.Map;
@@ -197,7 +197,7 @@ public class Trade {
             return;
         }
 
-        if (getItemStack() != null && !user.getBase().getInventory().containsAtLeast(itemStack, itemStack.getAmount())) {
+        if (getItemStack() != null && !Inventories.containsAtLeast(user.getBase(), itemStack, itemStack.getAmount())) {
             future.completeExceptionally(new ChargeException(tl("missingItems", getItemStack().getAmount(), ess.getItemDb().name(getItemStack()))));
             return;
         }
@@ -225,52 +225,33 @@ public class Trade {
             user.giveMoney(getMoney());
         }
         if (getItemStack() != null) {
-            // This stores the would be overflow
-            final Map<Integer, ItemStack> overFlow = InventoryWorkaround.addAllItems(user.getBase().getInventory(), getItemStack());
+            if (type == OverflowType.ABORT && !Inventories.hasSpace(user.getBase(), 0, false, getItemStack())) {
+                if (ess.getSettings().isDebug()) {
+                    ess.getLogger().log(Level.INFO, "abort paying " + user.getName() + " itemstack " + getItemStack().toString() + " due to lack of inventory space ");
+                }
+                return Collections.singletonMap(0, getItemStack());
+            }
 
-            if (overFlow != null) {
-                switch (type) {
-                    case ABORT:
-                        if (ess.getSettings().isDebug()) {
-                            ess.getLogger().log(Level.INFO, "abort paying " + user.getName() + " itemstack " + getItemStack().toString() + " due to lack of inventory space ");
+            final Map<Integer, ItemStack> leftover = Inventories.addItem(user.getBase(), getItemStack());
+            user.getBase().updateInventory();
+            if (!leftover.isEmpty()) {
+                if (type == OverflowType.RETURN) {
+                    if (ess.getSettings().isDebug()) {
+                        ess.getLogger().log(Level.INFO, "paying " + user.getName() + " partial itemstack " + getItemStack().toString() + " with overflow " + leftover.get(0).toString());
+                    }
+                    return leftover;
+                } else {
+                    for (final ItemStack itemStack : leftover.values()) {
+                        int spillAmount = itemStack.getAmount();
+                        itemStack.setAmount(Math.min(spillAmount, itemStack.getMaxStackSize()));
+                        while (spillAmount > 0) {
+                            user.getBase().getWorld().dropItemNaturally(user.getBase().getLocation(), itemStack);
+                            spillAmount -= itemStack.getAmount();
                         }
-
-                        return overFlow;
-
-                    case RETURN:
-                        // Pay the user the items, and return overflow
-                        final Map<Integer, ItemStack> returnStack = InventoryWorkaround.addItems(user.getBase().getInventory(), getItemStack());
-                        user.getBase().updateInventory();
-
-                        if (ess.getSettings().isDebug()) {
-                            ess.getLogger().log(Level.INFO, "paying " + user.getName() + " partial itemstack " + getItemStack().toString() + " with overflow " + returnStack.get(0).toString());
-                        }
-
-                        return returnStack;
-                    case DROP:
-                        // Pay the users the items directly, and drop the rest, will always return no overflow.
-                        final Map<Integer, ItemStack> leftOver = InventoryWorkaround.addItems(user.getBase().getInventory(), getItemStack());
-                        final Location loc = user.getBase().getLocation();
-                        for (final ItemStack loStack : leftOver.values()) {
-                            final int maxStackSize = loStack.getType().getMaxStackSize();
-                            final int stacks = loStack.getAmount() / maxStackSize;
-                            final int leftover = loStack.getAmount() % maxStackSize;
-                            final Item[] itemStacks = new Item[stacks + (leftover > 0 ? 1 : 0)];
-                            for (int i = 0; i < stacks; i++) {
-                                final ItemStack stack = loStack.clone();
-                                stack.setAmount(maxStackSize);
-                                itemStacks[i] = loc.getWorld().dropItem(loc, stack);
-                            }
-                            if (leftover > 0) {
-                                final ItemStack stack = loStack.clone();
-                                stack.setAmount(leftover);
-                                itemStacks[stacks] = loc.getWorld().dropItem(loc, stack);
-                            }
-                        }
-                        if (ess.getSettings().isDebug()) {
-                            ess.getLogger().log(Level.INFO, "paying " + user.getName() + " partial itemstack " + getItemStack().toString() + " and dropping overflow " + leftOver.get(0).toString());
-                        }
-                        break;
+                    }
+                    if (ess.getSettings().isDebug()) {
+                        ess.getLogger().log(Level.INFO, "paying " + user.getName() + " partial itemstack " + getItemStack().toString() + " and dropping overflow " + leftover.get(0).toString());
+                    }
                 }
             } else if (ess.getSettings().isDebug()) {
                 ess.getLogger().log(Level.INFO, "paying " + user.getName() + " itemstack " + getItemStack().toString());
@@ -315,11 +296,11 @@ public class Trade {
             if (ess.getSettings().isDebug()) {
                 ess.getLogger().log(Level.INFO, "charging user " + user.getName() + " itemstack " + getItemStack().toString());
             }
-            if (!user.getBase().getInventory().containsAtLeast(getItemStack(), getItemStack().getAmount())) {
+            if (!Inventories.containsAtLeast(user.getBase(), getItemStack(), getItemStack().getAmount())) {
                 future.completeExceptionally(new ChargeException(tl("missingItems", getItemStack().getAmount(), getItemStack().getType().toString().toLowerCase(Locale.ENGLISH).replace("_", " "))));
                 return;
             }
-            user.getBase().getInventory().removeItem(getItemStack());
+            Inventories.removeItemAmount(user.getBase(), getItemStack(), getItemStack().getAmount());
             user.getBase().updateInventory();
         }
         if (command != null) {

Essentials/src/main/java/com/earth2me/essentials/UUIDMap.java

@@ -1,155 +1,19 @@
 package com.earth2me.essentials;
 
-import com.google.common.io.Files;
-
-import java.io.BufferedReader;
-import java.io.BufferedWriter;
-import java.io.File;
-import java.io.FileReader;
-import java.io.FileWriter;
-import java.io.IOException;
-import java.util.ArrayList;
-import java.util.HashMap;
-import java.util.Map;
-import java.util.UUID;
-import java.util.concurrent.ConcurrentSkipListMap;
-import java.util.concurrent.Executors;
-import java.util.concurrent.ScheduledExecutorService;
-import java.util.concurrent.TimeUnit;
-import java.util.logging.Level;
-import java.util.regex.Pattern;
-
+@Deprecated
 public class UUIDMap {
-    private static final ScheduledExecutorService writeScheduler = Executors.newScheduledThreadPool(1);
-    private static boolean pendingWrite;
-    private static boolean loading = false;
-    private final transient net.ess3.api.IEssentials ess;
-    private final File userList;
-    private final transient Pattern splitPattern = Pattern.compile(",");
-    private final Runnable writeTaskRunnable;
-
-    public UUIDMap(final net.ess3.api.IEssentials ess) {
-        this.ess = ess;
-        userList = new File(ess.getDataFolder(), "usermap.csv");
-        pendingWrite = false;
-        writeTaskRunnable = () -> {
-            if (pendingWrite) {
-                try {
-                    new WriteRunner(ess.getDataFolder(), userList, ess.getUserMap().getNames()).run();
-                } catch (final Throwable t) { // bad code to prevent task from being suppressed
-                    t.printStackTrace();
-                }
-            }
-        };
-        writeScheduler.scheduleWithFixedDelay(writeTaskRunnable, 5, 5, TimeUnit.SECONDS);
-    }
-
-    public void loadAllUsers(final ConcurrentSkipListMap<String, UUID> names, final ConcurrentSkipListMap<UUID, ArrayList<String>> history) {
-        try {
-            if (!userList.exists()) {
-                userList.createNewFile();
-            }
-
-            if (ess.getSettings().isDebug()) {
-                ess.getLogger().log(Level.INFO, "Reading usermap from disk");
-            }
-
-            if (loading) {
-                return;
-            }
-
-            names.clear();
-            history.clear();
-            loading = true;
-
-            try (final BufferedReader reader = new BufferedReader(new FileReader(userList))) {
-                while (true) {
-                    final String line = reader.readLine();
-                    if (line == null) {
-                        break;
-                    } else {
-                        final String[] values = splitPattern.split(line);
-                        if (values.length == 2) {
-                            final String name = values[0];
-                            final UUID uuid = UUID.fromString(values[1]);
-                            names.put(name, uuid);
-                            if (!history.containsKey(uuid)) {
-                                final ArrayList<String> list = new ArrayList<>();
-                                list.add(name);
-                                history.put(uuid, list);
-                            } else {
-                                final ArrayList<String> list = history.get(uuid);
-                                if (!list.contains(name)) {
-                                    list.add(name);
-                                }
-                            }
-                        }
-                    }
-                }
-            }
-            loading = false;
-        } catch (final IOException ex) {
-            Essentials.getWrappedLogger().log(Level.SEVERE, ex.getMessage(), ex);
-        }
+    public UUIDMap() {
     }
 
     public void writeUUIDMap() {
-        pendingWrite = true;
+        //no-op
     }
 
     public void forceWriteUUIDMap() {
-        if (ess.getSettings().isDebug()) {
-            ess.getLogger().log(Level.INFO, "Forcing usermap write to disk");
-        }
-        pendingWrite = true;
-        writeTaskRunnable.run();
+        //no-op
     }
 
     public void shutdown() {
-        writeScheduler.submit(writeTaskRunnable);
-        writeScheduler.shutdown();
-    }
-
-    private static final class WriteRunner implements Runnable {
-        private final File location;
-        private final File endFile;
-        private final Map<String, UUID> names;
-
-        private WriteRunner(final File location, final File endFile, final Map<String, UUID> names) {
-            this.location = location;
-            this.endFile = endFile;
-            this.names = new HashMap<>(names);
-        }
-
-        @Override
-        public void run() {
-            pendingWrite = false;
-            if (loading || names.isEmpty()) {
-                return;
-            }
-            File configFile = null;
-
-            try {
-                configFile = File.createTempFile("usermap", ".tmp.csv", location);
-
-                final BufferedWriter bWriter = new BufferedWriter(new FileWriter(configFile));
-                for (final Map.Entry<String, UUID> entry : names.entrySet()) {
-                    bWriter.write(entry.getKey() + "," + entry.getValue().toString());
-                    bWriter.newLine();
-                }
-
-                bWriter.close();
-                Files.move(configFile, endFile);
-            } catch (final IOException ex) {
-                try {
-                    if (configFile != null && configFile.exists()) {
-                        Files.move(configFile, new File(endFile.getParentFile(), "usermap.bak.csv"));
-                    }
-                } catch (final Exception ex2) {
-                    Essentials.getWrappedLogger().log(Level.SEVERE, ex2.getMessage(), ex2);
-                }
-                Essentials.getWrappedLogger().log(Level.WARNING, ex.getMessage(), ex);
-            }
-        }
+        //no-op
     }
 }

Essentials/src/main/java/com/earth2me/essentials/User.java

@@ -1,6 +1,7 @@
 package com.earth2me.essentials;
 
 import com.earth2me.essentials.commands.IEssentialsCommand;
+import com.earth2me.essentials.craftbukkit.Inventories;
 import com.earth2me.essentials.economy.EconomyLayer;
 import com.earth2me.essentials.economy.EconomyLayers;
 import com.earth2me.essentials.messaging.IMessageRecipient;
@@ -27,7 +28,6 @@ import org.bukkit.block.Block;
 import org.bukkit.entity.Player;
 import org.bukkit.event.player.PlayerTeleportEvent.TeleportCause;
 import org.bukkit.inventory.ItemStack;
-import org.bukkit.inventory.PlayerInventory;
 import org.bukkit.metadata.FixedMetadataValue;
 import org.bukkit.potion.PotionEffect;
 import org.bukkit.potion.PotionEffectType;
@@ -90,6 +90,7 @@ public class User extends UserData implements Comparable<User>, IMessageRecipien
     private String lastHomeConfirmation;
     private long lastHomeConfirmationTimestamp;
     private Boolean toggleShout;
+    private boolean freeze = false;
     private transient final List<String> signCopy = Lists.newArrayList("", "", "", "");
     private transient long lastVanishTime = System.currentTimeMillis();
 
@@ -106,7 +107,7 @@ public class User extends UserData implements Comparable<User>, IMessageRecipien
         this.messageRecipient = new SimpleMessageRecipient(ess, this);
     }
 
-    void update(final Player base) {
+    public void update(final Player base) {
         setBase(base);
     }
 
@@ -151,7 +152,7 @@ public class User extends UserData implements Comparable<User>, IMessageRecipien
     }
 
     private boolean isAuthorizedCheck(final String node) {
-        if (base instanceof OfflinePlayer) {
+        if (base instanceof OfflinePlayerStub) {
             return false;
         }
 
@@ -169,7 +170,7 @@ public class User extends UserData implements Comparable<User>, IMessageRecipien
     }
 
     private boolean isPermSetCheck(final String node) {
-        if (base instanceof OfflinePlayer) {
+        if (base instanceof OfflinePlayerStub) {
             return false;
         }
 
@@ -187,7 +188,7 @@ public class User extends UserData implements Comparable<User>, IMessageRecipien
     }
 
     private TriState isAuthorizedExactCheck(final String node) {
-        if (base instanceof OfflinePlayer) {
+        if (base instanceof OfflinePlayerStub) {
             return TriState.UNSET;
         }
 
@@ -310,7 +311,7 @@ public class User extends UserData implements Comparable<User>, IMessageRecipien
 
     private void _dispose() {
         if (!base.isOnline()) {
-            this.base = new OfflinePlayer(getConfigUUID(), ess.getServer());
+            this.base = new OfflinePlayerStub(getConfigUUID(), ess.getServer());
         }
         cleanup();
     }
@@ -464,7 +465,11 @@ public class User extends UserData implements Comparable<User>, IMessageRecipien
         } else if (nick.equalsIgnoreCase(getName())) {
             nickname = nick;
         } else {
-            nickname = FormatUtil.replaceFormat(ess.getSettings().getNicknamePrefix()) + nick;
+            if (isAuthorized("essentials.nick.hideprefix")) {
+                nickname = nick;
+            } else {
+                nickname = FormatUtil.replaceFormat(ess.getSettings().getNicknamePrefix()) + nick;
+            }
             suffix = "§r";
         }
 
@@ -674,6 +679,9 @@ public class User extends UserData implements Comparable<User>, IMessageRecipien
 
     @Override
     public boolean isHiddenFrom(Player player) {
+        if (getBase() instanceof OfflinePlayerStub || player instanceof OfflinePlayerStub) {
+            return true;
+        }
         return !player.canSee(getBase());
     }
 
@@ -701,7 +709,7 @@ public class User extends UserData implements Comparable<User>, IMessageRecipien
     }
 
     public boolean isHidden(final Player player) {
-        return hidden || !player.canSee(getBase());
+        return hidden || isHiddenFrom(player);
     }
 
     @Override
@@ -1137,12 +1145,7 @@ public class User extends UserData implements Comparable<User>, IMessageRecipien
      * Returns the {@link ItemStack} in the main hand or off-hand. If the main hand is empty then the offhand item is returned - also nullable.
      */
     public ItemStack getItemInHand() {
-        if (VersionUtil.getServerBukkitVersion().isLowerThan(VersionUtil.v1_9_R01)) {
-            return getBase().getInventory().getItemInHand();
-        } else {
-            final PlayerInventory inventory = getBase().getInventory();
-            return inventory.getItemInMainHand() != null ? inventory.getItemInMainHand() : inventory.getItemInOffHand();
-        }
+        return Inventories.getItemInHand(getBase());
     }
 
     @Override
@@ -1192,6 +1195,16 @@ public class User extends UserData implements Comparable<User>, IMessageRecipien
         return signCopy;
     }
 
+    @Override
+    public boolean isFreeze() {
+        return freeze;
+    }
+
+    @Override
+    public void setFreeze(boolean freeze) {
+        this.freeze = freeze;
+    }
+
     public boolean isBaltopExempt() {
         if (getBase().isOnline()) {
             final boolean exempt = isAuthorized("essentials.balancetop.exclude");

Essentials/src/main/java/com/earth2me/essentials/UserData.java

@@ -5,6 +5,7 @@ import com.earth2me.essentials.config.EssentialsUserConfiguration;
 import com.earth2me.essentials.config.entities.CommandCooldown;
 import com.earth2me.essentials.config.entities.LazyLocation;
 import com.earth2me.essentials.config.holders.UserConfigHolder;
+import com.earth2me.essentials.userstorage.ModernUserMap;
 import com.earth2me.essentials.utils.NumberUtil;
 import com.earth2me.essentials.utils.StringUtil;
 import com.google.common.base.Charsets;
@@ -16,7 +17,6 @@ import org.bukkit.Location;
 import org.bukkit.Material;
 import org.bukkit.entity.Player;
 import org.bukkit.inventory.ItemStack;
-import org.spongepowered.configurate.serialize.SerializationException;
 
 import java.io.File;
 import java.math.BigDecimal;
@@ -43,19 +43,14 @@ public abstract class UserData extends PlayerExtension implements IConf {
         super(base);
         this.ess = ess;
         final File folder = new File(ess.getDataFolder(), "userdata");
-        if (!folder.exists()) {
-            folder.mkdirs();
+        if (!folder.exists() && !folder.mkdirs()) {
+            throw new RuntimeException("Unable to create userdata folder!");
         }
 
-        String filename;
-        try {
-            filename = base.getUniqueId().toString();
-        } catch (final Throwable ex) {
-            ess.getLogger().warning("Falling back to old username system for " + base.getName());
-            filename = base.getName();
-        }
-
-        config = new EssentialsUserConfiguration(base.getName(), base.getUniqueId(), new File(folder, filename + ".yml"));
+        config = new EssentialsUserConfiguration(base.getName(), base.getUniqueId(), new File(folder, base.getUniqueId() + ".yml"));
+        config.setSaveHook(() -> {
+            config.setRootHolder(UserConfigHolder.class, holder);
+        });
         reloadConfig();
 
         if (config.getUsername() == null) {
@@ -65,12 +60,15 @@ public abstract class UserData extends PlayerExtension implements IConf {
 
     public final void reset() {
         config.blockingSave();
-        config.getFile().delete();
+        if (!config.getFile().delete()) {
+            ess.getLogger().warning("Unable to delete data file for " + config.getFile().getName());
+        }
         if (config.getUsername() != null) {
-            ess.getUserMap().removeUser(config.getUsername());
+            final ModernUserMap users = (ModernUserMap) ess.getUsers();
+            users.invalidate(config.getUuid());
             if (isNPC()) {
-                final String uuid = UUID.nameUUIDFromBytes(("NPC:" + StringUtil.safeString(config.getUsername())).getBytes(Charsets.UTF_8)).toString();
-                ess.getUserMap().removeUserUUID(uuid);
+                final String name = ess.getSettings().isSafeUsermap() ? StringUtil.safeString(config.getUsername()) : config.getUsername();
+                users.invalidate(UUID.nameUUIDFromBytes(("NPC:" + name).getBytes(Charsets.UTF_8)));
             }
         }
     }
@@ -84,18 +82,10 @@ public abstract class UserData extends PlayerExtension implements IConf {
         config.load();
         try {
             holder = config.getRootNode().get(UserConfigHolder.class);
-        } catch (SerializationException e) {
+        } catch (Throwable e) {
             ess.getLogger().log(Level.SEVERE, "Error while reading user config: " + config.getFile().getName(), e);
             throw new RuntimeException(e);
         }
-        config.setSaveHook(() -> {
-            try {
-                config.getRootNode().set(UserConfigHolder.class, holder);
-            } catch (SerializationException e) {
-                ess.getLogger().log(Level.SEVERE, "Error while saving user config: " + config.getFile().getName(), e);
-                throw new RuntimeException(e);
-            }
-        });
         money = _getMoney();
     }
 
@@ -208,6 +198,16 @@ public abstract class UserData extends PlayerExtension implements IConf {
         }
     }
 
+    public void renameHome(final String name, final String newName) throws Exception {
+        final LazyLocation location = holder.homes().remove(name);
+        if (location != null) {
+            holder.homes().put(StringUtil.safeString(newName), location);
+            config.save();
+        } else {
+            throw new Exception(tl("invalidHome", name));
+        }
+    }
+
     public boolean hasHome() {
         return !holder.homes().isEmpty();
     }
@@ -589,9 +589,13 @@ public abstract class UserData extends PlayerExtension implements IConf {
     }
 
     public void setLastAccountName(final String lastAccountName) {
+        if (getLastAccountName() != null && !getLastAccountName().equals(lastAccountName)) {
+            final List<String> usernames = holder.pastUsernames();
+            usernames.add(0, getLastAccountName());
+            holder.pastUsernames(usernames);
+        }
         holder.lastAccountName(lastAccountName);
         config.save();
-        ess.getUserMap().trackUUID(getConfigUUID(), lastAccountName, true);
     }
 
     public boolean arePowerToolsEnabled() {
@@ -722,6 +726,17 @@ public abstract class UserData extends PlayerExtension implements IConf {
         config.save();
     }
 
+    public List<String> getPastUsernames() {
+        return holder.pastUsernames();
+    }
+
+    public void addPastUsername(String username) {
+        final List<String> usernames = holder.pastUsernames();
+        usernames.add(0, username);
+        holder.pastUsernames(usernames);
+        config.save();
+    }
+
     public boolean isShouting() {
         if (holder.shouting() == null) {
             holder.shouting(ess.getSettings().isShoutDefault());

Essentials/src/main/java/com/earth2me/essentials/UserMap.java

@@ -1,383 +1,70 @@
 package com.earth2me.essentials;
 
 import com.earth2me.essentials.api.UserDoesNotExistException;
-import com.earth2me.essentials.utils.StringUtil;
-import com.google.common.base.Charsets;
-import com.google.common.cache.Cache;
-import com.google.common.cache.CacheBuilder;
-import com.google.common.cache.CacheLoader;
-import com.google.common.cache.LoadingCache;
-import com.google.common.util.concurrent.UncheckedExecutionException;
-import net.ess3.api.IEssentials;
-import net.ess3.api.MaxMoneyException;
+import com.earth2me.essentials.userstorage.ModernUserMap;
+import org.bukkit.Bukkit;
 import org.bukkit.entity.Player;
 
-import java.io.File;
-import java.lang.reflect.InvocationTargetException;
-import java.lang.reflect.Method;
-import java.text.MessageFormat;
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.List;
 import java.util.Set;
 import java.util.UUID;
 import java.util.concurrent.ConcurrentSkipListMap;
-import java.util.concurrent.ConcurrentSkipListSet;
-import java.util.concurrent.ExecutionException;
-import java.util.logging.Level;
-import java.util.regex.Pattern;
 
-public class UserMap extends CacheLoader<String, User> implements IConf {
-    private static boolean legacy = false;
-    private static Method getLegacy;
-    private final transient IEssentials ess;
-    private final transient ConcurrentSkipListSet<UUID> keys = new ConcurrentSkipListSet<>();
-    private final transient ConcurrentSkipListMap<String, UUID> names = new ConcurrentSkipListMap<>();
-    private final transient ConcurrentSkipListMap<UUID, ArrayList<String>> history = new ConcurrentSkipListMap<>();
-    private final UUIDMap uuidMap;
-    private final transient Cache<String, User> users;
-    private final Pattern validUserPattern = Pattern.compile("^[a-zA-Z0-9_]{2,16}$");
+@Deprecated
+public class UserMap {
+    private final transient ModernUserMap userMap;
+    private final transient UUIDMap uuidMap;
 
-    private static final String WARN_UUID_NOT_REPLACE = "Found UUID {0} for player {1}, but player already has a UUID ({2}). Not replacing UUID in usermap.";
-
-    public UserMap(final IEssentials ess) {
-        super();
-        this.ess = ess;
-        uuidMap = new UUIDMap(ess);
-        //RemovalListener<UUID, User> remListener = new UserMapRemovalListener();
-        //users = CacheBuilder.newBuilder().maximumSize(ess.getSettings().getMaxUserCacheCount()).softValues().removalListener(remListener).build(this);
-        final CacheBuilder<Object, Object> cacheBuilder = CacheBuilder.newBuilder();
-        final int maxCount = ess.getSettings().getMaxUserCacheCount();
-        try {
-            cacheBuilder.maximumSize(maxCount);
-        } catch (final NoSuchMethodError nsme) {
-            legacy = true;
-            legacyMaximumSize(cacheBuilder, maxCount);
-        }
-        cacheBuilder.softValues();
-        if (!legacy) {
-            users = cacheBuilder.build(this);
-        } else {
-            users = legacyBuild(cacheBuilder);
-        }
-    }
-
-    private void loadAllUsersAsync(final IEssentials ess) {
-        ess.runTaskAsynchronously(() -> {
-            synchronized (users) {
-                final File userdir = new File(ess.getDataFolder(), "userdata");
-                if (!userdir.exists()) {
-                    return;
-                }
-                keys.clear();
-                users.invalidateAll();
-                for (final String string : userdir.list()) {
-                    if (!string.endsWith(".yml")) {
-                        continue;
-                    }
-                    final String name = string.substring(0, string.length() - 4);
-                    try {
-                        keys.add(UUID.fromString(name));
-                    } catch (final IllegalArgumentException ex) {
-                        //Ignore these users till they rejoin.
-                    }
-                }
-                uuidMap.loadAllUsers(names, history);
-            }
-        });
-    }
-
-    public boolean userExists(final UUID uuid) {
-        return keys.contains(uuid);
+    public UserMap(final ModernUserMap userMap) {
+        this.userMap = userMap;
+        this.uuidMap = new UUIDMap();
     }
 
     public User getUser(final String name) {
-        final String sanitizedName = StringUtil.safeString(name);
-        try {
-            if (ess.getSettings().isDebug()) {
-                ess.getLogger().warning("Looking up username " + name + " (" + sanitizedName + ") ...");
-            }
-
-            if (names.containsKey(sanitizedName)) {
-                final UUID uuid = names.get(sanitizedName);
-                return getUser(uuid);
-            }
-
-            if (ess.getSettings().isDebug()) {
-                ess.getLogger().warning(name + "(" + sanitizedName + ") has no known usermap entry");
-            }
-
-            final File userFile = getUserFileFromString(sanitizedName);
-            if (userFile.exists()) {
-                ess.getLogger().info("Importing user " + name + " to usermap.");
-                final User user = new User(new OfflinePlayer(sanitizedName, ess.getServer()), ess);
-                trackUUID(user.getBase().getUniqueId(), user.getName(), true);
-                return user;
-            }
-            return null;
-        } catch (final UncheckedExecutionException ex) {
-            if (ess.getSettings().isDebug()) {
-                ess.getLogger().log(Level.WARNING, ex, () -> String.format("Exception while getting user for %s (%s)", name, sanitizedName));
-            }
-            return null;
-        }
+        return userMap.getUser(name);
     }
 
     public User getUser(final UUID uuid) {
-        try {
-            if (!legacy) {
-                return ((LoadingCache<String, User>) users).get(uuid.toString());
-            } else {
-                return legacyCacheGet(uuid);
-            }
-        } catch (final ExecutionException | UncheckedExecutionException ex) {
-            if (ess.getSettings().isDebug()) {
-                ess.getLogger().log(Level.WARNING, ex, () -> "Exception while getting user for " + uuid);
-            }
-            return null;
-        }
+        return userMap.getUser(uuid);
     }
 
     public void trackUUID(final UUID uuid, final String name, final boolean replace) {
-        if (uuid != null) {
-            keys.add(uuid);
-            if (name != null && name.length() > 0) {
-                final String keyName = ess.getSettings().isSafeUsermap() ? StringUtil.safeString(name) : name;
-                if (!names.containsKey(keyName)) {
-                    names.put(keyName, uuid);
-                    uuidMap.writeUUIDMap();
-                } else if (!isUUIDMatch(uuid, keyName)) {
-                    if (replace) {
-                        ess.getLogger().info("Found new UUID for " + name + ". Replacing " + names.get(keyName).toString() + " with " + uuid.toString());
-                        names.put(keyName, uuid);
-                        uuidMap.writeUUIDMap();
-                    } else {
-                        ess.getLogger().log(Level.INFO, MessageFormat.format(WARN_UUID_NOT_REPLACE, uuid.toString(), name, names.get(keyName).toString()), new RuntimeException());
-                    }
-                }
-            }
-        }
+        // no-op
     }
 
-    public boolean isUUIDMatch(final UUID uuid, final String name) {
-        return names.containsKey(name) && names.get(name).equals(uuid);
-    }
-
-    @Override
     public User load(final String stringUUID) throws Exception {
-        final UUID uuid = UUID.fromString(stringUUID);
-        Player player = ess.getServer().getPlayer(uuid);
-        if (player != null) {
-            final User user = new User(player, ess);
-            trackUUID(uuid, user.getName(), true);
-            return user;
-        }
-
-        final File userFile = getUserFileFromID(uuid);
-
-        if (userFile.exists()) {
-            player = new OfflinePlayer(uuid, ess.getServer());
-            final User user = new User(player, ess);
-            ((OfflinePlayer) player).setName(user.getLastAccountName());
-            trackUUID(uuid, user.getName(), false);
-            return user;
-        }
-
-        throw new Exception("User not found!");
+        return userMap.load(UUID.fromString(stringUUID));
     }
 
     public User load(final org.bukkit.OfflinePlayer player) throws UserDoesNotExistException {
-        if (player == null) {
-            throw new IllegalArgumentException("Player cannot be null!");
-        }
-
+        final Player userPlayer;
         if (player instanceof Player) {
-            if (ess.getSettings().isDebug()) {
-                ess.getLogger().info("Loading online OfflinePlayer into user map...");
-            }
-            final User user = new User((Player) player, ess);
-            trackUUID(player.getUniqueId(), player.getName(), true);
-            return user;
-        }
-
-        final File userFile = getUserFileFromID(player.getUniqueId());
-        if (ess.getSettings().isDebug()) {
-            ess.getLogger().info("Loading OfflinePlayer into user map. Has data: " + userFile.exists() + " for " + player);
-        }
-
-        final OfflinePlayer essPlayer = new OfflinePlayer(player.getUniqueId(), ess.getServer());
-        final User user = new User(essPlayer, ess);
-        if (userFile.exists()) {
-            essPlayer.setName(user.getLastAccountName());
+            userPlayer = (Player) player;
         } else {
-            if (ess.getSettings().isDebug()) {
-                ess.getLogger().info("OfflinePlayer usermap load saving user data for " + player);
-            }
-
-            // this code makes me sad
-            user.startTransaction();
-            try {
-                user.setMoney(ess.getSettings().getStartingBalance());
-            } catch (MaxMoneyException e) {
-                // Shouldn't happen as it would be an illegal configuration state
-                throw new RuntimeException(e);
-            }
-            user.setLastAccountName(user.getName());
-            user.stopTransaction();
+            final OfflinePlayerStub essPlayer = new OfflinePlayerStub(player.getUniqueId(), Bukkit.getServer());
+            essPlayer.setName(player.getName());
+            userPlayer = essPlayer;
         }
 
-        trackUUID(player.getUniqueId(), user.getName(), false);
+        final User user = userMap.getUser(userPlayer);
+        if (user == null) {
+            throw new UserDoesNotExistException("User not found");
+        }
         return user;
     }
 
-    @Override
-    public void reloadConfig() {
-        getUUIDMap().forceWriteUUIDMap();
-        loadAllUsersAsync(ess);
-    }
-
-    public void invalidateAll() {
-        users.invalidateAll();
-    }
-
-    public void removeUser(final String name) {
-        if (names == null) {
-            ess.getLogger().warning("Name collection is null, cannot remove user.");
-            return;
-        }
-        final UUID uuid = names.get(name);
-        if (uuid != null) {
-            keys.remove(uuid);
-            users.invalidate(uuid.toString());
-        }
-        names.remove(name);
-        names.remove(StringUtil.safeString(name));
-    }
-
-    public void removeUserUUID(final String uuid) {
-        users.invalidate(uuid);
-    }
-
     public Set<UUID> getAllUniqueUsers() {
-        return Collections.unmodifiableSet(keys);
+        return userMap.getAllUserUUIDs();
     }
 
     public int getUniqueUsers() {
-        return keys.size();
+        return userMap.getUserCount();
     }
 
     protected ConcurrentSkipListMap<String, UUID> getNames() {
-        return names;
-    }
-
-    protected ConcurrentSkipListMap<UUID, ArrayList<String>> getHistory() {
-        return history;
-    }
-
-    public List<String> getUserHistory(final UUID uuid) {
-        return history.get(uuid);
+        return new ConcurrentSkipListMap<>(userMap.getNameCache());
     }
 
     public UUIDMap getUUIDMap() {
         return uuidMap;
     }
-    //  class UserMapRemovalListener implements RemovalListener
-    //  {
-    //      @Override
-    //      public void onRemoval(final RemovalNotification notification)
-    //      {
-    //          Object value = notification.getValue();
-    //          if (value != null)
-    //          {
-    //              ((User)value).cleanup();
-    //          }
-    //      }
-    //  }
-
-    private File getUserFileFromID(final UUID uuid) {
-        final File userFolder = new File(ess.getDataFolder(), "userdata");
-        return new File(userFolder, uuid.toString() + ".yml");
-    }
-
-    public File getUserFileFromString(final String name) {
-        final File userFolder = new File(ess.getDataFolder(), "userdata");
-        return new File(userFolder, StringUtil.sanitizeFileName(name) + ".yml");
-    }
-
-    @SuppressWarnings("deprecation")
-    public User getUserFromBukkit(String name) {
-        name = StringUtil.safeString(name);
-        if (ess.getSettings().isDebug()) {
-            ess.getLogger().warning("Using potentially blocking Bukkit UUID lookup for: " + name);
-        }
-        // Don't attempt to look up entirely invalid usernames
-        if (name == null || !validUserPattern.matcher(name).matches()) {
-            return null;
-        }
-        final org.bukkit.OfflinePlayer offlinePlayer = ess.getServer().getOfflinePlayer(name);
-        if (offlinePlayer == null) {
-            return null;
-        }
-        final UUID uuid;
-        try {
-            uuid = offlinePlayer.getUniqueId();
-        } catch (final UnsupportedOperationException | NullPointerException e) {
-            return null;
-        }
-        // This is how Bukkit generates fake UUIDs
-        if (UUID.nameUUIDFromBytes(("OfflinePlayer:" + name).getBytes(Charsets.UTF_8)).equals(uuid)) {
-            return null;
-        } else {
-            names.put(name, uuid);
-            return getUser(uuid);
-        }
-    }
-
-    private User legacyCacheGet(final UUID uuid) {
-        if (getLegacy == null) {
-            final Class<?> usersClass = users.getClass();
-            for (final Method m : usersClass.getDeclaredMethods()) {
-                if (m.getName().equals("get")) {
-                    getLegacy = m;
-                    getLegacy.setAccessible(true);
-                    break;
-                }
-            }
-        }
-        try {
-            return (User) getLegacy.invoke(users, uuid.toString());
-        } catch (final IllegalAccessException | InvocationTargetException e) {
-            return null;
-        }
-    }
-
-    private void legacyMaximumSize(final CacheBuilder builder, final int maxCount) {
-        try {
-            final Method maxSizeLegacy = builder.getClass().getDeclaredMethod("maximumSize", Integer.TYPE);
-            maxSizeLegacy.setAccessible(true);
-            maxSizeLegacy.invoke(builder, maxCount);
-        } catch (final NoSuchMethodException | InvocationTargetException | IllegalAccessException e) {
-            e.printStackTrace();
-        }
-    }
-
-    @SuppressWarnings("unchecked")
-    private Cache<String, User> legacyBuild(final CacheBuilder builder) {
-        Method build = null;
-        for (final Method method : builder.getClass().getDeclaredMethods()) {
-            if (method.getName().equals("build")) {
-                build = method;
-                break;
-            }
-        }
-        Cache<String, User> legacyUsers;
-        try {
-            assert build != null;
-            build.setAccessible(true);
-            legacyUsers = (Cache<String, User>) build.invoke(builder, this);
-        } catch (final IllegalAccessException | InvocationTargetException e) {
-            legacyUsers = null;
-        }
-        return legacyUsers;
-    }
 }

Essentials/src/main/java/com/earth2me/essentials/Warps.java

@@ -121,7 +121,7 @@ public class Warps implements IConf, net.ess3.api.IWarps {
     public final void reloadConfig() {
         warpPoints.clear();
         final File[] listOfFiles = warpsFolder.listFiles();
-        if (listOfFiles.length >= 1) {
+        if (listOfFiles != null) {
             for (final File listOfFile : listOfFiles) {
                 final String filename = listOfFile.getName();
                 if (listOfFile.isFile() && filename.endsWith(".yml")) {

Essentials/src/main/java/com/earth2me/essentials/Worth.java

@@ -3,6 +3,7 @@ package com.earth2me.essentials;
 import com.earth2me.essentials.commands.NotEnoughArgumentsException;
 import com.earth2me.essentials.config.ConfigurateUtil;
 import com.earth2me.essentials.config.EssentialsConfiguration;
+import com.earth2me.essentials.craftbukkit.Inventories;
 import com.earth2me.essentials.utils.VersionUtil;
 import org.bukkit.Material;
 import org.bukkit.inventory.ItemStack;
@@ -101,7 +102,7 @@ public class Worth implements IConf {
         }
 
         int max = 0;
-        for (final ItemStack s : user.getBase().getInventory().getContents()) {
+        for (final ItemStack s : Inventories.getInventory(user.getBase(), false)) {
             if (s == null || !s.isSimilar(is)) {
                 continue;
             }

Essentials/src/main/java/com/earth2me/essentials/api/Economy.java

@@ -3,6 +3,7 @@ package com.earth2me.essentials.api;
 import com.earth2me.essentials.Trade;
 import com.earth2me.essentials.User;
 import com.earth2me.essentials.config.EssentialsUserConfiguration;
+import com.earth2me.essentials.userstorage.ModernUserMap;
 import com.earth2me.essentials.utils.NumberUtil;
 import com.earth2me.essentials.utils.StringUtil;
 import com.google.common.base.Charsets;
@@ -41,9 +42,9 @@ public class Economy {
         ess = aEss;
     }
 
-    private static void createNPCFile(String name) {
+    private static void createNPCFile(final String unsanitizedName) {
         final File folder = new File(ess.getDataFolder(), "userdata");
-        name = StringUtil.safeString(name);
+        final String name = ess.getSettings().isSafeUsermap() ? StringUtil.safeString(unsanitizedName) : unsanitizedName;
         if (!folder.exists()) {
             if (!folder.mkdirs()) {
                 throw new RuntimeException("Error while creating userdata directory!");
@@ -59,9 +60,12 @@ public class Economy {
         npcConfig.load();
         npcConfig.setProperty("npc", true);
         npcConfig.setProperty("last-account-name", name);
+        npcConfig.setProperty("npc-name", unsanitizedName);
         npcConfig.setProperty("money", ess.getSettings().getStartingBalance());
         npcConfig.blockingSave();
-        ess.getUserMap().trackUUID(npcUUID, name, false);
+        // This will load the NPC into the UserMap + UUID cache
+        ((ModernUserMap) ess.getUsers()).addCachedNpcName(npcUUID, name);
+        ess.getUsers().getUser(npcUUID);
     }
 
     private static void deleteNPC(final String name) {

Essentials/src/main/java/com/earth2me/essentials/commands/Commandbalancetop.java

@@ -7,6 +7,7 @@ import com.earth2me.essentials.utils.NumberUtil;
 import com.google.common.collect.Lists;
 import net.essentialsx.api.v2.services.BalanceTop;
 import org.bukkit.Server;
+import org.bukkit.command.BlockCommandSender;
 
 import java.math.BigDecimal;
 import java.text.DateFormat;
@@ -32,8 +33,15 @@ public class Commandbalancetop extends EssentialsCommand {
         final Calendar cal = Calendar.getInstance();
         cal.setTimeInMillis(ess.getBalanceTop().getCacheAge());
         final DateFormat format = DateFormat.getDateTimeInstance(DateFormat.SHORT, DateFormat.SHORT);
-        sender.sendMessage(tl("balanceTop", format.format(cal.getTime())));
-        new TextPager(cache).showPage(Integer.toString(page), null, "balancetop", sender);
+        final Runnable runnable = () -> {
+            sender.sendMessage(tl("balanceTop", format.format(cal.getTime())));
+            new TextPager(cache).showPage(Integer.toString(page), null, "balancetop", sender);
+        };
+        if (sender.getSender() instanceof BlockCommandSender) {
+            ess.scheduleSyncDelayedTask(runnable);
+        } else {
+            runnable.run();
+        }
     }
 
     @Override
@@ -56,8 +64,8 @@ public class Commandbalancetop extends EssentialsCommand {
         }
 
         // If there are less than 50 users in our usermap, there is no need to display a warning as these calculations should be done quickly
-        if (ess.getUserMap().getUniqueUsers() > MINUSERS) {
-            sender.sendMessage(tl("orderBalances", ess.getUserMap().getUniqueUsers()));
+        if (ess.getUsers().getUserCount() > MINUSERS) {
+            sender.sendMessage(tl("orderBalances", ess.getUsers().getUserCount()));
         }
 
         ess.runTaskAsynchronously(new Viewer(sender, page, force));

Essentials/src/main/java/com/earth2me/essentials/commands/Commandban.java

@@ -2,7 +2,7 @@ package com.earth2me.essentials.commands;
 
 import com.earth2me.essentials.CommandSource;
 import com.earth2me.essentials.Console;
-import com.earth2me.essentials.OfflinePlayer;
+import com.earth2me.essentials.OfflinePlayerStub;
 import com.earth2me.essentials.User;
 import com.earth2me.essentials.utils.FormatUtil;
 import org.bukkit.BanList;
@@ -30,7 +30,7 @@ public class Commandban extends EssentialsCommand {
             user = getPlayer(server, args, 0, true, true);
         } catch (final PlayerNotFoundException e) {
             nomatch = true;
-            user = ess.getUser(new OfflinePlayer(args[0], ess.getServer()));
+            user = ess.getUser(new OfflinePlayerStub(args[0], ess.getServer()));
         }
         if (!user.getBase().isOnline()) {
             if (sender.isPlayer() && !ess.getUser(sender.getPlayer()).isAuthorized("essentials.ban.offline")) {
@@ -54,7 +54,7 @@ public class Commandban extends EssentialsCommand {
         final String banDisplay = tl("banFormat", banReason, senderDisplayName);
 
         user.getBase().kickPlayer(banDisplay);
-        server.getLogger().log(Level.INFO, tl("playerBanned", senderDisplayName, user.getName(), banDisplay));
+        ess.getLogger().log(Level.INFO, tl("playerBanned", senderDisplayName, user.getName(), banDisplay));
 
         if (nomatch) {
             sender.sendMessage(tl("userUnknown", user.getName()));

Essentials/src/main/java/com/earth2me/essentials/commands/Commandbanip.java

@@ -54,7 +54,7 @@ public class Commandbanip extends EssentialsCommand {
         final String banDisplay = tl("banFormat", banReason, senderDisplayName);
 
         ess.getServer().getBanList(BanList.Type.IP).addBan(ipAddress, banReason, null, senderName);
-        server.getLogger().log(Level.INFO, tl("playerBanIpAddress", senderDisplayName, ipAddress, banReason));
+        ess.getLogger().log(Level.INFO, tl("playerBanIpAddress", senderDisplayName, ipAddress, banReason));
 
         for (final Player player : ess.getServer().getOnlinePlayers()) {
             if (player.getAddress().getAddress().getHostAddress().equalsIgnoreCase(ipAddress)) {

Essentials/src/main/java/com/earth2me/essentials/commands/Commandbook.java

@@ -2,7 +2,7 @@ package com.earth2me.essentials.commands;
 
 import com.earth2me.essentials.User;
 import com.earth2me.essentials.utils.FormatUtil;
-import com.earth2me.essentials.craftbukkit.InventoryWorkaround;
+import com.earth2me.essentials.craftbukkit.Inventories;
 import com.earth2me.essentials.utils.EnumUtil;
 import com.google.common.collect.Lists;
 import org.bukkit.Material;
@@ -25,7 +25,7 @@ public class Commandbook extends EssentialsCommand {
 
     @Override
     public void run(final Server server, final User user, final String commandLabel, final String[] args) throws Exception {
-        final ItemStack item = user.getItemInHand();
+        final ItemStack item = Inventories.getItemInMainHand(user.getBase());
         final String player = user.getName();
         if (item.getType() == Material.WRITTEN_BOOK) {
             final BookMeta bmeta = (BookMeta) item.getItemMeta();
@@ -52,7 +52,7 @@ public class Commandbook extends EssentialsCommand {
                 if (isAuthor(bmeta, player) || user.isAuthorized("essentials.book.others")) {
                     final ItemStack newItem = new ItemStack(WRITABLE_BOOK, item.getAmount());
                     newItem.setItemMeta(bmeta);
-                    InventoryWorkaround.setItemInMainHand(user.getBase(), newItem);
+                    Inventories.setItemInMainHand(user.getBase(), newItem);
                     user.sendMessage(tl("editBookContents"));
                 } else {
                     throw new Exception(tl("denyBookEdit"));
@@ -65,7 +65,7 @@ public class Commandbook extends EssentialsCommand {
             }
             final ItemStack newItem = new ItemStack(Material.WRITTEN_BOOK, item.getAmount());
             newItem.setItemMeta(bmeta);
-            InventoryWorkaround.setItemInMainHand(user.getBase(), newItem);
+            Inventories.setItemInMainHand(user.getBase(), newItem);
             user.sendMessage(tl("bookLocked"));
         } else {
             throw new Exception(tl("holdBook"));

Essentials/src/main/java/com/earth2me/essentials/commands/Commandbottom.java

@@ -0,0 +1,36 @@
+package com.earth2me.essentials.commands;
+
+import com.earth2me.essentials.Trade;
+import com.earth2me.essentials.User;
+import com.earth2me.essentials.utils.LocationUtil;
+import org.bukkit.Location;
+import org.bukkit.Server;
+import org.bukkit.event.player.PlayerTeleportEvent;
+
+import java.util.concurrent.CompletableFuture;
+
+import static com.earth2me.essentials.I18n.tl;
+
+public class Commandbottom extends EssentialsCommand {
+
+    public Commandbottom() {
+        super("bottom");
+    }
+
+    @Override
+    public void run(final Server server, final User user, final String commandLabel, final String[] args) throws Exception {
+        final int bottomX = user.getLocation().getBlockX();
+        final int bottomZ = user.getLocation().getBlockZ();
+        final float pitch = user.getLocation().getPitch();
+        final float yaw = user.getLocation().getYaw();
+        final Location unsafe = new Location(user.getWorld(), bottomX, ess.getWorldInfoProvider().getMinHeight(user.getWorld()), bottomZ, yaw, pitch);
+        final Location safe = LocationUtil.getSafeDestination(ess, unsafe);
+        final CompletableFuture<Boolean> future = getNewExceptionFuture(user.getSource(), commandLabel);
+        future.thenAccept(success -> {
+            if (success) {
+                user.sendMessage(tl("teleportBottom", safe.getWorld().getName(), safe.getBlockX(), safe.getBlockY(), safe.getBlockZ()));
+            }
+        });
+        user.getAsyncTeleport().teleport(safe, new Trade(this.getName(), ess), PlayerTeleportEvent.TeleportCause.COMMAND, future);
+    }
+}

Essentials/src/main/java/com/earth2me/essentials/commands/Commandclearinventory.java

@@ -2,7 +2,7 @@ package com.earth2me.essentials.commands;
 
 import com.earth2me.essentials.CommandSource;
 import com.earth2me.essentials.User;
-import com.earth2me.essentials.craftbukkit.InventoryWorkaround;
+import com.earth2me.essentials.craftbukkit.Inventories;
 import com.earth2me.essentials.utils.NumberUtil;
 import com.earth2me.essentials.utils.StringUtil;
 import com.earth2me.essentials.utils.VersionUtil;
@@ -22,8 +22,6 @@ import java.util.Set;
 import static com.earth2me.essentials.I18n.tl;
 
 public class Commandclearinventory extends EssentialsCommand {
-
-    private static final int BASE_AMOUNT = 100000;
     private static final int EXTENDED_CAP = 8;
 
     public Commandclearinventory() {
@@ -114,38 +112,30 @@ public class Commandclearinventory extends EssentialsCommand {
             }
         }
 
-        if (type == ClearHandlerType.ALL_EXCEPT_ARMOR) {
+        if (type != ClearHandlerType.SPECIFIC_ITEM) {
+            final boolean armor = type == ClearHandlerType.ALL_INCLUDING_ARMOR;
             if (showExtended) {
-                sender.sendMessage(tl("inventoryClearingAllItems", player.getDisplayName()));
+                sender.sendMessage(tl(armor ? "inventoryClearingAllArmor" : "inventoryClearingAllItems", player.getDisplayName()));
             }
-            InventoryWorkaround.clearInventoryNoArmor(player.getInventory());
-            InventoryWorkaround.setItemInOffHand(player, null);
-        } else if (type == ClearHandlerType.ALL_INCLUDING_ARMOR) {
-            if (showExtended) {
-                sender.sendMessage(tl("inventoryClearingAllArmor", player.getDisplayName()));
-            }
-            InventoryWorkaround.clearInventoryNoArmor(player.getInventory());
-            InventoryWorkaround.setItemInOffHand(player, null);
-            player.getInventory().setArmorContents(null);
+            Inventories.removeItems(player, item -> true, armor);
         } else {
             for (final Item item : items) {
                 final ItemStack stack = new ItemStack(item.getMaterial());
                 if (VersionUtil.PRE_FLATTENING) {
+                    //noinspection deprecation
                     stack.setDurability(item.getData());
                 }
+
                 // amount -1 means all items will be cleared
                 if (amount == -1) {
-                    stack.setAmount(BASE_AMOUNT);
-                    final ItemStack removedStack = player.getInventory().removeItem(stack).get(0);
-                    final int removedAmount = BASE_AMOUNT - removedStack.getAmount() + InventoryWorkaround.clearItemInOffHand(player, stack);
+                    final int removedAmount = Inventories.removeItemSimilar(player, stack, true);
                     if (removedAmount > 0 || showExtended) {
                         sender.sendMessage(tl("inventoryClearingStack", removedAmount, stack.getType().toString().toLowerCase(Locale.ENGLISH), player.getDisplayName()));
                     }
                 } else {
                     stack.setAmount(amount < 0 ? 1 : amount);
-                    if (player.getInventory().containsAtLeast(stack, amount)) {
+                    if (Inventories.removeItemAmount(player, stack, amount)) {
                         sender.sendMessage(tl("inventoryClearingStack", amount, stack.getType().toString().toLowerCase(Locale.ENGLISH), player.getDisplayName()));
-                        player.getInventory().removeItem(stack);
                     } else {
                         if (showExtended) {
                             sender.sendMessage(tl("inventoryClearFail", player.getDisplayName(), amount, stack.getType().toString().toLowerCase(Locale.ENGLISH)));
@@ -203,7 +193,7 @@ public class Commandclearinventory extends EssentialsCommand {
     }
 
     private String formatCommand(final String commandLabel, final String[] args) {
-        return "/" + commandLabel + " " + StringUtil.joinList(" ", args);
+        return "/" + commandLabel + " " + StringUtil.joinList(" ", (Object[]) args);
     }
 
     private enum ClearHandlerType {

Essentials/src/main/java/com/earth2me/essentials/commands/Commandcondense.java

@@ -4,6 +4,7 @@ import com.earth2me.essentials.ChargeException;
 import com.earth2me.essentials.Trade;
 import com.earth2me.essentials.Trade.OverflowType;
 import com.earth2me.essentials.User;
+import com.earth2me.essentials.craftbukkit.Inventories;
 import com.earth2me.essentials.utils.VersionUtil;
 import net.ess3.api.MaxMoneyException;
 import org.bukkit.Material;
@@ -39,7 +40,7 @@ public class Commandcondense extends EssentialsCommand {
         if (args.length > 0) {
             is = ess.getItemDb().getMatching(user, args);
         } else {
-            for (final ItemStack stack : user.getBase().getInventory().getContents()) {
+            for (final ItemStack stack : Inventories.getInventory(user.getBase(), false)) {
                 if (stack == null || stack.getType() == Material.AIR) {
                     continue;
                 }
@@ -85,7 +86,7 @@ public class Commandcondense extends EssentialsCommand {
 
             int amount = 0;
 
-            for (final ItemStack contents : user.getBase().getInventory().getContents()) {
+            for (final ItemStack contents : Inventories.getInventory(user.getBase(), false)) {
                 if (contents != null && contents.isSimilar(stack)) {
                     amount += contents.getAmount();
                 }

Essentials/src/main/java/com/earth2me/essentials/commands/Commandcreatekit.java

@@ -2,6 +2,7 @@ package com.earth2me.essentials.commands;
 
 import com.earth2me.essentials.CommandSource;
 import com.earth2me.essentials.User;
+import com.earth2me.essentials.craftbukkit.Inventories;
 import com.earth2me.essentials.utils.DateUtil;
 import com.earth2me.essentials.utils.PasteUtil;
 import org.bukkit.Material;
@@ -37,7 +38,7 @@ public class Commandcreatekit extends EssentialsCommand {
         // Command handler will auto fail if this fails.
         final long delay = Long.parseLong(args[1]);
         final String kitname = args[0];
-        final ItemStack[] items = user.getBase().getInventory().getContents();
+        final ItemStack[] items = Inventories.getInventory(user.getBase(), true);
         final List<String> list = new ArrayList<>();
 
         boolean useSerializationProvider = ess.getSettings().isUseBetterKits();

Essentials/src/main/java/com/earth2me/essentials/commands/Commanddelhome.java

@@ -3,6 +3,8 @@ package com.earth2me.essentials.commands;
 import com.earth2me.essentials.CommandSource;
 import com.earth2me.essentials.IUser;
 import com.earth2me.essentials.User;
+import net.essentialsx.api.v2.events.HomeModifyEvent;
+import org.bukkit.Bukkit;
 import org.bukkit.Server;
 
 import java.util.ArrayList;
@@ -37,18 +39,27 @@ public class Commanddelhome extends EssentialsCommand {
 
         if (expandedArg.length > 1 && (user == null || user.isAuthorized("essentials.delhome.others"))) {
             user = getPlayer(server, expandedArg, 0, true, true);
-            name = expandedArg[1];
+            name = expandedArg[1].toLowerCase(Locale.ENGLISH);
         } else if (user == null) {
             throw new NotEnoughArgumentsException();
         } else {
-            name = expandedArg[0];
+            name = expandedArg[0].toLowerCase(Locale.ENGLISH);
         }
 
-        if (name.equalsIgnoreCase("bed")) {
+        if (name.equals("bed")) {
             throw new Exception(tl("invalidHomeName"));
         }
 
-        user.delHome(name.toLowerCase(Locale.ENGLISH));
+        final HomeModifyEvent event = new HomeModifyEvent(sender.getUser(ess), user, name, user.getHome(name), false);
+        Bukkit.getServer().getPluginManager().callEvent(event);
+        if (event.isCancelled()) {
+            if (ess.getSettings().isDebug()) {
+                ess.getLogger().info("HomeModifyEvent canceled for /delhome execution by " + sender.getDisplayName());
+            }
+            return;
+        }
+
+        user.delHome(name);
         sender.sendMessage(tl("deleteHome", name));
     }
 

Essentials/src/main/java/com/earth2me/essentials/commands/Commandeditsign.java

@@ -3,11 +3,22 @@ package com.earth2me.essentials.commands;
 import com.earth2me.essentials.User;
 import com.earth2me.essentials.utils.FormatUtil;
 import com.earth2me.essentials.utils.NumberUtil;
+import com.earth2me.essentials.utils.VersionUtil;
 import com.google.common.collect.Lists;
+import org.bukkit.Bukkit;
 import org.bukkit.ChatColor;
 import org.bukkit.Server;
 import org.bukkit.block.Block;
+import org.bukkit.block.BlockFace;
 import org.bukkit.block.Sign;
+import org.bukkit.block.data.BlockData;
+import org.bukkit.block.data.type.HangingSign;
+import org.bukkit.block.data.type.WallHangingSign;
+import org.bukkit.block.data.type.WallSign;
+import org.bukkit.block.sign.Side;
+import org.bukkit.entity.Player;
+import org.bukkit.event.block.SignChangeEvent;
+import org.bukkit.util.Vector;
 
 import java.util.Collections;
 import java.util.List;
@@ -29,48 +40,74 @@ public class Commandeditsign extends EssentialsCommand {
         if (!(target.getState() instanceof Sign)) {
             throw new Exception(tl("editsignCommandTarget"));
         }
-        final Sign sign = (Sign) target.getState();
+        final ModifiableSign sign = wrapSign((Sign) target.getState(), user);
         try {
             if (args[0].equalsIgnoreCase("set") && args.length > 2) {
+                final String[] existingLines = sign.getLines();
                 final int line = Integer.parseInt(args[1]) - 1;
                 final String text = FormatUtil.formatString(user, "essentials.editsign", getFinalArg(args, 2)).trim();
                 if (ChatColor.stripColor(text).length() > 15 && !user.isAuthorized("essentials.editsign.unlimited")) {
                     throw new Exception(tl("editsignCommandLimit"));
                 }
-                sign.setLine(line, text);
-                sign.update();
+                existingLines[line] = text;
+                if (callSignEvent(sign, user.getBase(), existingLines)) {
+                    return;
+                }
+
                 user.sendMessage(tl("editsignCommandSetSuccess", line + 1, text));
             } else if (args[0].equalsIgnoreCase("clear")) {
                 if (args.length == 1) {
+                    final String[] existingLines = sign.getLines();
                     for (int i = 0; i < 4; i++) { // A whole one line of line savings!
-                        sign.setLine(i, "");
+                        existingLines[i] = "";
                     }
-                    sign.update();
+
+                    if (callSignEvent(sign, user.getBase(), existingLines)) {
+                        return;
+                    }
+
                     user.sendMessage(tl("editsignCommandClear"));
                 } else {
+                    final String[] existingLines = sign.getLines();
                     final int line = Integer.parseInt(args[1]) - 1;
-                    sign.setLine(line, "");
-                    sign.update();
+                    existingLines[line] = "";
+
+                    if (callSignEvent(sign, user.getBase(), existingLines)) {
+                        return;
+                    }
+
                     user.sendMessage(tl("editsignCommandClearLine", line + 1));
                 }
-            } else if (args[0].equalsIgnoreCase("copy") || args[0].equalsIgnoreCase("paste")) {
-                final boolean copy = args[0].equalsIgnoreCase("copy");
-                final String tlPrefix = copy ? "editsignCopy" : "editsignPaste";
+            } else if (args[0].equalsIgnoreCase("copy")) {
                 final int line = args.length == 1 ? -1 : Integer.parseInt(args[1]) - 1;
 
                 if (line == -1) {
                     for (int i = 0; i < 4; i++) {
-                        processSignCopyPaste(user, sign, i, copy);
+                        // We use unformat here to prevent players from copying signs with colors that they do not have permission to use.
+                        user.getSignCopy().set(i, FormatUtil.unformatString(user, "essentials.editsign", sign.getLine(i)));
                     }
-                    user.sendMessage(tl(tlPrefix, commandLabel));
+                    user.sendMessage(tl("editsignCopy", commandLabel));
                 } else {
-                    processSignCopyPaste(user, sign, line, copy);
-                    user.sendMessage(tl(tlPrefix + "Line", line + 1, commandLabel));
+                    // We use unformat here to prevent players from copying signs with colors that they do not have permission to use.
+                    user.getSignCopy().set(line, FormatUtil.unformatString(user, "essentials.editsign", sign.getLine(line)));
+                    user.sendMessage(tl("editsignCopyLine", line + 1, commandLabel));
                 }
 
-                if (!copy) {
-                    sign.update();
+            } else if (args[0].equalsIgnoreCase("paste")) {
+                final int line = args.length == 1 ? -1 : Integer.parseInt(args[1]) - 1;
+
+                final String[] existingLines = sign.getLines();
+                if (line == -1) {
+                    for (int i = 0; i < 4; i++) {
+                        existingLines[i] = FormatUtil.formatString(user, "essentials.editsign", user.getSignCopy().get(i));
+                    }
+                    user.sendMessage(tl("editsignPaste", commandLabel));
+                } else {
+                    existingLines[line] = FormatUtil.formatString(user, "essentials.editsign", user.getSignCopy().get(line));
+                    user.sendMessage(tl("editsignPasteLine", line + 1, commandLabel));
                 }
+
+                callSignEvent(sign, user.getBase(), existingLines);
             } else {
                 throw new NotEnoughArgumentsException();
             }
@@ -79,15 +116,28 @@ public class Commandeditsign extends EssentialsCommand {
         }
     }
 
-    private void processSignCopyPaste(final User user, final Sign sign, final int index, final boolean copy) {
-        if (copy) {
-            // We use unformat here to prevent players from copying signs with colors that they do not have permission to use.
-            user.getSignCopy().set(index, FormatUtil.unformatString(user, "essentials.editsign", sign.getLine(index)));
-            return;
+    private boolean callSignEvent(final ModifiableSign sign, final Player player, final String[] lines) {
+        final SignChangeEvent event;
+        if (VersionUtil.getServerBukkitVersion().isHigherThanOrEqualTo(VersionUtil.v1_20_1_R01)) {
+            event = new SignChangeEvent(sign.getBlock(), player, lines, sign.isFront() ? Side.FRONT : Side.BACK);
+        } else {
+            //noinspection deprecation
+            event = new SignChangeEvent(sign.getBlock(), player, lines);
         }
 
-        final String line = FormatUtil.formatString(user, "essentials.editsign", user.getSignCopy().get(index));
-        sign.setLine(index, line == null ? "" : line);
+        Bukkit.getServer().getPluginManager().callEvent(event);
+        if (event.isCancelled()) {
+            if (ess.getSettings().isDebug()) {
+                ess.getLogger().info("SignChangeEvent canceled for /editsign execution by " + player.getName());
+            }
+            return true;
+        }
+
+        for (int i = 0; i < 4; i++) {
+            sign.setLine(i, lines[i]);
+        }
+        sign.update();
+        return false;
     }
 
     @Override
@@ -100,7 +150,7 @@ public class Commandeditsign extends EssentialsCommand {
             final int line = Integer.parseInt(args[1]);
             final Block target = user.getTargetBlock(5);
             if (target.getState() instanceof Sign && line <= 4) {
-                final Sign sign = (Sign) target.getState();
+                final ModifiableSign sign = wrapSign((Sign) target.getState(), user);
                 return Lists.newArrayList(FormatUtil.unformatString(user, "essentials.editsign", sign.getLine(line - 1)));
             }
             return Collections.emptyList();
@@ -108,4 +158,93 @@ public class Commandeditsign extends EssentialsCommand {
             return Collections.emptyList();
         }
     }
+
+    private ModifiableSign wrapSign(final Sign sign, final User user) {
+        if (VersionUtil.getServerBukkitVersion().isHigherThanOrEqualTo(VersionUtil.v1_20_1_R01)) {
+            final Vector eyeLocLessSign = user.getBase().getEyeLocation().toVector().subtract(sign.getLocation().add(.5, .5, .5).toVector());
+            final BlockData signBlockData = sign.getBlockData();
+
+            final BlockFace signDirection;
+            if (signBlockData instanceof org.bukkit.block.data.type.Sign) {
+                signDirection = ((org.bukkit.block.data.type.Sign) signBlockData).getRotation();
+            } else if (signBlockData instanceof WallSign) {
+                signDirection = ((WallSign) signBlockData).getFacing();
+            } else if (signBlockData instanceof HangingSign) {
+                signDirection = ((HangingSign) signBlockData).getRotation();
+            } else if (signBlockData instanceof WallHangingSign) {
+                signDirection = ((WallHangingSign) signBlockData).getFacing();
+            } else {
+                throw new IllegalStateException("Unknown block data for sign: " + signBlockData.getClass());
+            }
+
+            final Side side = eyeLocLessSign.dot(signDirection.getDirection()) > 0 ? Side.FRONT : Side.BACK;
+
+            return new ModifiableSign(sign) {
+                @Override
+                String[] getLines() {
+                    return sign.getSide(side).getLines();
+                }
+
+                @Override
+                String getLine(int line) {
+                    return sign.getSide(side).getLine(line);
+                }
+
+                @Override
+                void setLine(int line, String text) {
+                    sign.getSide(side).setLine(line, text);
+                }
+
+                @Override
+                boolean isFront() {
+                    return side == Side.FRONT;
+                }
+            };
+        }
+        return new ModifiableSign(sign) {
+            @Override
+            String[] getLines() {
+                return sign.getLines();
+            }
+
+            @Override
+            String getLine(int line) {
+                return sign.getLine(line);
+            }
+
+            @Override
+            void setLine(int line, String text) {
+                sign.setLine(line, text);
+            }
+
+            @Override
+            boolean isFront() {
+                return true;
+            }
+        };
+    }
+
+    private abstract static class ModifiableSign {
+        protected final Sign sign;
+
+        protected ModifiableSign(final Sign sign) {
+            this.sign = sign;
+        }
+
+        abstract String getLine(int line);
+
+        abstract String[] getLines();
+
+        abstract void setLine(int line, String text);
+
+        abstract boolean isFront();
+
+        Block getBlock() {
+            return sign.getBlock();
+        }
+
+        void update() {
+            sign.update();
+        }
+    }
 }

Essentials/src/main/java/com/earth2me/essentials/commands/Commandenchant.java

@@ -3,7 +3,6 @@ package com.earth2me.essentials.commands;
 import com.earth2me.essentials.Enchantments;
 import com.earth2me.essentials.MetaItemStack;
 import com.earth2me.essentials.User;
-import com.earth2me.essentials.craftbukkit.InventoryWorkaround;
 import com.earth2me.essentials.utils.StringUtil;
 import com.google.common.collect.Lists;
 import org.bukkit.Material;
@@ -57,7 +56,7 @@ public class Commandenchant extends EssentialsCommand {
         final MetaItemStack metaStack = new MetaItemStack(stack);
         final Enchantment enchantment = metaStack.getEnchantment(user, args[0]);
         metaStack.addEnchantment(user.getSource(), ess.getSettings().allowUnsafeEnchantments() && user.isAuthorized("essentials.enchantments.allowunsafe"), enchantment, level);
-        InventoryWorkaround.setItemInMainHand(user.getBase(), metaStack.getItemStack());
+        stack.setItemMeta(metaStack.getItemStack().getItemMeta());
         user.getBase().updateInventory();
         final String enchantName = enchantment.getName().toLowerCase(Locale.ENGLISH).replace('_', ' ');
         if (level == 0) {

Essentials/src/main/java/com/earth2me/essentials/commands/Commandessentials.java

@@ -3,9 +3,10 @@ package com.earth2me.essentials.commands;
 import com.earth2me.essentials.CommandSource;
 import com.earth2me.essentials.EssentialsUpgrade;
 import com.earth2me.essentials.User;
-import com.earth2me.essentials.UserMap;
+import com.earth2me.essentials.craftbukkit.Inventories;
 import com.earth2me.essentials.economy.EconomyLayer;
 import com.earth2me.essentials.economy.EconomyLayers;
+import com.earth2me.essentials.userstorage.ModernUserMap;
 import com.earth2me.essentials.utils.CommandMapUtil;
 import com.earth2me.essentials.utils.DateUtil;
 import com.earth2me.essentials.utils.EnumUtil;
@@ -13,7 +14,6 @@ import com.earth2me.essentials.utils.FloatUtil;
 import com.earth2me.essentials.utils.NumberUtil;
 import com.earth2me.essentials.utils.PasteUtil;
 import com.earth2me.essentials.utils.VersionUtil;
-import com.google.common.base.Charsets;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.Lists;
 import com.google.gson.JsonArray;
@@ -23,16 +23,19 @@ import com.google.gson.JsonPrimitive;
 import org.bukkit.Bukkit;
 import org.bukkit.ChatColor;
 import org.bukkit.Location;
+import org.bukkit.Material;
 import org.bukkit.Server;
 import org.bukkit.Sound;
 import org.bukkit.World;
 import org.bukkit.command.Command;
 import org.bukkit.entity.Player;
+import org.bukkit.inventory.ItemStack;
 import org.bukkit.plugin.Plugin;
 import org.bukkit.plugin.PluginDescriptionFile;
 import org.bukkit.plugin.PluginManager;
 import org.bukkit.scheduler.BukkitRunnable;
 
+import java.io.File;
 import java.io.IOException;
 import java.lang.management.ManagementFactory;
 import java.nio.charset.StandardCharsets;
@@ -45,12 +48,15 @@ import java.util.Collection;
 import java.util.Collections;
 import java.util.Comparator;
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.List;
 import java.util.Locale;
 import java.util.Map;
+import java.util.Set;
 import java.util.UUID;
 import java.util.concurrent.CompletableFuture;
 import java.util.function.Supplier;
+import java.util.logging.Level;
 import java.util.stream.Collectors;
 
 import static com.earth2me.essentials.I18n.tl;
@@ -90,6 +96,7 @@ public class Commandessentials extends EssentialsCommand {
         "EssentialsAntiBuild",
         "EssentialsChat",
         "EssentialsDiscord",
+        "EssentialsDiscordLink",
         "EssentialsGeoIP",
         "EssentialsProtect",
         "EssentialsSpawn",
@@ -147,11 +154,12 @@ public class Commandessentials extends EssentialsCommand {
             case "homes":
                 runHomes(server, sender, commandLabel, args);
                 break;
-            case "uuidconvert":
-                runUUIDConvert(server, sender, commandLabel, args);
+            case "usermap":
+                runUserMap(sender, args);
                 break;
-            case "uuidtest":
-                runUUIDTest(server, sender, commandLabel, args);
+
+            case "itemtest":
+                runItemTest(server, sender, commandLabel, args);
                 break;
 
             // "#EasterEgg"
@@ -168,6 +176,56 @@ public class Commandessentials extends EssentialsCommand {
         }
     }
 
+    public void runItemTest(Server server, CommandSource sender, String commandLabel, String[] args) {
+        if (!sender.isAuthorized("essentials.itemtest", ess) || args.length < 2 || !sender.isPlayer()) {
+            return;
+        }
+
+        final Player player = sender.getPlayer();
+        assert player != null;
+
+        switch (args[1]) {
+            case "slot": {
+                if (args.length < 3) {
+                    return;
+                }
+                player.getInventory().setItem(Integer.parseInt(args[2]), new ItemStack(Material.DIRT));
+                break;
+            }
+            case "overfill": {
+                sender.sendMessage(Inventories.addItem(player, 42, false, new ItemStack(Material.DIAMOND_SWORD, 1), new ItemStack(Material.DIRT, 32), new ItemStack(Material.DIRT, 32)).toString());
+                break;
+            }
+            case "overfill2": {
+                if (args.length < 4) {
+                    return;
+                }
+                final boolean armor = Boolean.parseBoolean(args[2]);
+                final boolean add = Boolean.parseBoolean(args[3]);
+                final ItemStack[] items = new ItemStack[]{new ItemStack(Material.DIAMOND_SWORD, 1), new ItemStack(Material.DIRT, 32), new ItemStack(Material.DIRT, 32), new ItemStack(Material.DIAMOND_HELMET, 4), new ItemStack(Material.CHAINMAIL_LEGGINGS, 1)};
+                if (Inventories.hasSpace(player, 0, armor, items)) {
+                    if (add) {
+                        sender.sendMessage(Inventories.addItem(player, 0, armor, items).toString());
+                    }
+                    sender.sendMessage("SO MUCH SPACE!");
+                } else {
+                    sender.sendMessage("No space!");
+                }
+                break;
+            }
+            case "remove": {
+                if (args.length < 3) {
+                    return;
+                }
+                Inventories.removeItemExact(player, new ItemStack(Material.PUMPKIN, 1), Boolean.parseBoolean(args[2]));
+                break;
+            }
+            default: {
+                break;
+            }
+        }
+    }
+
     // Displays the command's usage.
     private void showUsage(final CommandSource sender) throws Exception {
         throw new NotEnoughArgumentsException();
@@ -270,6 +328,7 @@ public class Commandessentials extends EssentialsCommand {
         files.add(new PasteUtil.PasteFile("dump.json", dump.toString()));
 
         final Plugin essDiscord = Bukkit.getPluginManager().getPlugin("EssentialsDiscord");
+        final Plugin essDiscordLink = Bukkit.getPluginManager().getPlugin("EssentialsDiscordLink");
         final Plugin essSpawn = Bukkit.getPluginManager().getPlugin("EssentialsSpawn");
 
         final Map<String, Command> knownCommandsCopy = new HashMap<>(ess.getKnownCommandsProvider().getKnownCommands());
@@ -331,6 +390,15 @@ public class Commandessentials extends EssentialsCommand {
                 } catch (IOException e) {
                     sender.sendMessage(tl("dumpErrorUpload", "discord-config.yml", e.getMessage()));
                 }
+
+                if (essDiscordLink != null) {
+                    try {
+                        files.add(new PasteUtil.PasteFile("discord-link-config.yml",
+                                new String(Files.readAllBytes(essDiscordLink.getDataFolder().toPath().resolve("config.yml")), StandardCharsets.UTF_8)));
+                    } catch (IOException e) {
+                        sender.sendMessage(tl("dumpErrorUpload", "discord-link-config.yml", e.getMessage()));
+                    }
+                }
             }
 
             if (kits) {
@@ -473,12 +541,11 @@ public class Commandessentials extends EssentialsCommand {
         final long daysArg = Long.parseLong(args[1]);
         final double moneyArg = args.length >= 3 ? FloatUtil.parseDouble(args[2].replaceAll("[^0-9\\.]", "")) : 0;
         final int homesArg = args.length >= 4 && NumberUtil.isInt(args[3]) ? Integer.parseInt(args[3]) : 0;
-        final UserMap userMap = ess.getUserMap();
 
         ess.runTaskAsynchronously(() -> {
             final long currTime = System.currentTimeMillis();
-            for (final UUID u : userMap.getAllUniqueUsers()) {
-                final User user = ess.getUserMap().getUser(u);
+            for (final UUID u : ess.getUsers().getAllUserUUIDs()) {
+                final User user = ess.getUsers().loadUncachedUser(u);
                 if (user == null) {
                     continue;
                 }
@@ -523,13 +590,12 @@ public class Commandessentials extends EssentialsCommand {
             throw new Exception(HOMES_USAGE);
         }
 
-        final UserMap userMap = ess.getUserMap();
         switch (args[1]) {
             case "fix":
                 sender.sendMessage(tl("fixingHomes"));
                 ess.runTaskAsynchronously(() -> {
-                    for (final UUID u : userMap.getAllUniqueUsers()) {
-                        final User user = ess.getUserMap().getUser(u);
+                    for (final UUID u : ess.getUsers().getAllUserUUIDs()) {
+                        final User user = ess.getUsers().loadUncachedUser(u);
                         if (user == null) {
                             continue;
                         }
@@ -553,8 +619,8 @@ public class Commandessentials extends EssentialsCommand {
                 }
                 sender.sendMessage(filterByWorld ? tl("deletingHomesWorld", args[2]) : tl("deletingHomes"));
                 ess.runTaskAsynchronously(() -> {
-                    for (final UUID u : userMap.getAllUniqueUsers()) {
-                        final User user = ess.getUserMap().getUser(u);
+                    for (final UUID u : ess.getUsers().getAllUserUUIDs()) {
+                        final User user = ess.getUsers().loadUncachedUser(u);
                         if (user == null) {
                             continue;
                         }
@@ -577,52 +643,79 @@ public class Commandessentials extends EssentialsCommand {
         }
     }
 
-    // Forces a rerun of userdata UUID conversion.
-    private void runUUIDConvert(final Server server, final CommandSource sender, final String commandLabel, final String[] args) throws Exception {
-        sender.sendMessage("Starting Essentials UUID userdata conversion; this may lag the server.");
-
-        final Boolean ignoreUFCache = args.length > 2 && args[1].toLowerCase(Locale.ENGLISH).contains("ignore");
-        EssentialsUpgrade.uuidFileConvert(ess, ignoreUFCache);
-
-        sender.sendMessage("UUID conversion complete. Check your server log for more information.");
-    }
-
-    // Looks up various UUIDs for a user.
-    private void runUUIDTest(final Server server, final CommandSource sender, final String commandLabel, final String[] args) throws Exception {
-        if (args.length < 2) {
-            throw new Exception("/<command> uuidtest <name>");
+    // Gets information about cached users
+    private void runUserMap(final CommandSource sender, final String[] args) {
+        if (!sender.isAuthorized("essentials.usermap", ess)) {
+            return;
         }
-        final String name = args[1];
-        sender.sendMessage("Looking up UUID for " + name);
 
-        UUID onlineUUID = null;
+        final ModernUserMap userMap = (ModernUserMap) ess.getUsers();
+        sender.sendMessage(tl("usermapSize", userMap.getCachedCount(), userMap.getUserCount(), ess.getSettings().getMaxUserCacheCount()));
+        if (args.length > 1) {
+            if (args[1].equals("full")) {
+                for (final Map.Entry<String, UUID> entry : userMap.getNameCache().entrySet()) {
+                    sender.sendMessage(tl("usermapEntry", entry.getKey(), entry.getValue().toString()));
+                }
+            } else if (args[1].equals("purge")) {
+                final boolean seppuku = args.length > 2 && args[2].equals("iknowwhatimdoing");
 
-        for (final Player player : ess.getOnlinePlayers()) {
-            if (player.getName().equalsIgnoreCase(name)) {
-                onlineUUID = player.getUniqueId();
-                break;
+                sender.sendMessage(tl("usermapPurge", String.valueOf(seppuku)));
+
+                final Set<UUID> uuids = new HashSet<>(ess.getUsers().getAllUserUUIDs());
+                ess.runTaskAsynchronously(() -> {
+                    final File userdataFolder = new File(ess.getDataFolder(), "userdata");
+                    final File backupFolder = new File(ess.getDataFolder(), "userdata-npc-backup-boogaloo-" + System.currentTimeMillis());
+
+                    if (!userdataFolder.isDirectory()) {
+                        ess.getLogger().warning("Missing userdata folder, aborting usermap purge.");
+                        return;
+                    }
+
+                    if (seppuku && !backupFolder.mkdir()) {
+                        ess.getLogger().warning("Unable to create backup folder, aborting usermap purge.");
+                        return;
+                    }
+
+                    int total = 0;
+                    final File[] files = userdataFolder.listFiles(EssentialsUpgrade.YML_FILTER);
+                    if (files != null) {
+                        for (final File file : files) {
+                            try {
+                                final String fileName = file.getName();
+                                final UUID uuid = UUID.fromString(fileName.substring(0, fileName.length() - 4));
+                                if (!uuids.contains(uuid)) {
+                                    total++;
+                                    ess.getLogger().warning("Found orphaned userdata file: " + file.getName());
+                                    if (seppuku) {
+                                        try {
+                                            com.google.common.io.Files.move(file, new File(backupFolder, file.getName()));
+                                        } catch (IOException e) {
+                                            ess.getLogger().log(Level.WARNING, "Unable to move orphaned userdata file: " + file.getName(), e);
+                                        }
+                                    }
+                                }
+                            } catch (IllegalArgumentException ignored) {
+                            }
+                        }
+                    }
+                    ess.getLogger().info("Found " + total + " orphaned userdata files.");
+                });
+            } else if (args[1].equalsIgnoreCase("cache")) {
+                sender.sendMessage(tl("usermapKnown", ess.getUsers().getAllUserUUIDs().size(), ess.getUsers().getNameCache().size()));
+            } else {
+                try {
+                    final UUID uuid = UUID.fromString(args[1]);
+                    for (final Map.Entry<String, UUID> entry : userMap.getNameCache().entrySet()) {
+                        if (entry.getValue().equals(uuid)) {
+                            sender.sendMessage(tl("usermapEntry", entry.getKey(), args[1]));
+                        }
+                    }
+                } catch (IllegalArgumentException ignored) {
+                    final String sanitizedName = userMap.getSanitizedName(args[1]);
+                    sender.sendMessage(tl("usermapEntry", sanitizedName, userMap.getNameCache().get(sanitizedName).toString()));
+                }
             }
         }
-
-        final UUID essUUID = ess.getUserMap().getUser(name).getConfigUUID();
-
-        final org.bukkit.OfflinePlayer player = ess.getServer().getOfflinePlayer(name);
-        final UUID bukkituuid = player.getUniqueId();
-        sender.sendMessage("Bukkit Lookup: " + bukkituuid.toString());
-
-        if (onlineUUID != null && onlineUUID != bukkituuid) {
-            sender.sendMessage("Online player: " + onlineUUID.toString());
-        }
-
-        if (essUUID != null && essUUID != bukkituuid) {
-            sender.sendMessage("Essentials config: " + essUUID.toString());
-        }
-
-        final UUID npcuuid = UUID.nameUUIDFromBytes(("NPC:" + name).getBytes(Charsets.UTF_8));
-        sender.sendMessage("NPC UUID: " + npcuuid.toString());
-
-        final UUID offlineuuid = UUID.nameUUIDFromBytes(("OfflinePlayer:" + name).getBytes(Charsets.UTF_8));
-        sender.sendMessage("Offline Mode UUID: " + offlineuuid.toString());
     }
 
     // Displays versions of EssentialsX and related plugins.
@@ -750,7 +843,6 @@ public class Commandessentials extends EssentialsCommand {
             options.add("cleanup");
             options.add("homes");
             //options.add("uuidconvert");
-            //options.add("uuidtest");
             //options.add("nya");
             //options.add("moo");
             return options;
@@ -763,7 +855,6 @@ public class Commandessentials extends EssentialsCommand {
                 }
                 break;
             case "reset":
-            case "uuidtest":
                 if (args.length == 2) {
                     return getPlayers(server, sender);
                 }
@@ -782,11 +873,6 @@ public class Commandessentials extends EssentialsCommand {
                     return server.getWorlds().stream().map(World::getName).collect(Collectors.toList());
                 }
                 break;
-            case "uuidconvert":
-                if (args.length == 2) {
-                    return Lists.newArrayList("ignoreUFCache");
-                }
-                break;
             case "dump":
                 final List<String> list = Lists.newArrayList("config", "kits", "log", "discord", "worth", "tpr", "spawns", "commands", "all");
                 for (String arg : args) {

Essentials/src/main/java/com/earth2me/essentials/commands/Commandgive.java

@@ -3,7 +3,7 @@ package com.earth2me.essentials.commands;
 import com.earth2me.essentials.CommandSource;
 import com.earth2me.essentials.MetaItemStack;
 import com.earth2me.essentials.User;
-import com.earth2me.essentials.craftbukkit.InventoryWorkaround;
+import com.earth2me.essentials.craftbukkit.Inventories;
 import com.earth2me.essentials.utils.NumberUtil;
 import com.earth2me.essentials.utils.VersionUtil;
 import com.google.common.collect.Lists;
@@ -81,13 +81,8 @@ public class Commandgive extends EssentialsLoopCommand {
         final ItemStack finalStack = stack;
         loopOnlinePlayersConsumer(server, sender, false, true, args[0], player -> {
             sender.sendMessage(tl("giveSpawn", finalStack.getAmount(), itemName, player.getDisplayName()));
-            final Map<Integer, ItemStack> leftovers;
 
-            if (player.isAuthorized("essentials.oversizedstacks")) {
-                leftovers = InventoryWorkaround.addOversizedItems(player.getBase().getInventory(), ess.getSettings().getOversizedStackSize(), finalStack);
-            } else {
-                leftovers = InventoryWorkaround.addItems(player.getBase().getInventory(), finalStack);
-            }
+            final Map<Integer, ItemStack> leftovers = Inventories.addItem(player.getBase(), player.isAuthorized("essentials.oversizedstacks") ? ess.getSettings().getOversizedStackSize() : 0, finalStack);
 
             for (final ItemStack item : leftovers.values()) {
                 if (isDropItemsIfFull) {

Essentials/src/main/java/com/earth2me/essentials/commands/Commandhat.java

@@ -1,7 +1,7 @@
 package com.earth2me.essentials.commands;
 
 import com.earth2me.essentials.User;
-import com.earth2me.essentials.craftbukkit.InventoryWorkaround;
+import com.earth2me.essentials.craftbukkit.Inventories;
 import com.earth2me.essentials.utils.TriState;
 import com.earth2me.essentials.utils.VersionUtil;
 import com.google.common.collect.Lists;
@@ -28,7 +28,7 @@ public class Commandhat extends EssentialsCommand {
     @Override
     protected void run(final Server server, final User user, final String commandLabel, final String[] args) throws Exception {
         if (args.length == 0 || (!args[0].contains("rem") && !args[0].contains("off") && !args[0].equalsIgnoreCase("0"))) {
-            final ItemStack hand = user.getItemInHand();
+            final ItemStack hand = Inventories.getItemInMainHand(user.getBase());
             if (hand == null || hand.getType() == Material.AIR) {
                 user.sendMessage(tl("hatFail"));
                 return;
@@ -53,7 +53,7 @@ public class Commandhat extends EssentialsCommand {
                 return;
             }
             inv.setHelmet(hand);
-            inv.setItemInHand(head);
+            Inventories.setItemInMainHand(user.getBase(), head);
             user.sendMessage(tl("hatPlaced"));
             return;
         }
@@ -67,7 +67,7 @@ public class Commandhat extends EssentialsCommand {
         } else {
             final ItemStack air = new ItemStack(Material.AIR);
             inv.setHelmet(air);
-            InventoryWorkaround.addItems(user.getBase().getInventory(), head);
+            Inventories.addItem(user.getBase(), head);
             user.sendMessage(tl("hatRemoved"));
         }
     }

Essentials/src/main/java/com/earth2me/essentials/commands/Commandhelpop.java

@@ -36,7 +36,7 @@ public class Commandhelpop extends EssentialsCommand {
             throw new NotEnoughArgumentsException();
         }
         final String message = tl("helpOp", from, FormatUtil.stripFormat(getFinalArg(args, 0)));
-        server.getLogger().log(Level.INFO, message);
+        ess.getLogger().log(Level.INFO, message);
         ess.broadcastMessage("essentials.helpop.receive", message);
         return message;
     }

Essentials/src/main/java/com/earth2me/essentials/commands/Commandhome.java

@@ -1,6 +1,6 @@
 package com.earth2me.essentials.commands;
 
-import com.earth2me.essentials.OfflinePlayer;
+import com.earth2me.essentials.OfflinePlayerStub;
 import com.earth2me.essentials.Trade;
 import com.earth2me.essentials.User;
 import com.earth2me.essentials.utils.StringUtil;
@@ -42,7 +42,7 @@ public class Commandhome extends EssentialsCommand {
         }
         try {
             if ("bed".equalsIgnoreCase(homeName) && user.isAuthorized("essentials.home.bed")) {
-                if (!player.getBase().isOnline() || player.getBase() instanceof OfflinePlayer) {
+                if (!player.getBase().isOnline() || player.getBase() instanceof OfflinePlayerStub) {
                     throw new Exception(tl("bedOffline"));
                 }
                 PaperLib.getBedSpawnLocationAsync(player.getBase(), true).thenAccept(location -> {
@@ -101,7 +101,7 @@ public class Commandhome extends EssentialsCommand {
                     user.sendMessage(tl("homes", StringUtil.joinList(homes), count, getHomeLimit(finalPlayer)));
                 }
             });
-            if (!player.getBase().isOnline() || player.getBase() instanceof OfflinePlayer) {
+            if (!player.getBase().isOnline() || player.getBase() instanceof OfflinePlayerStub) {
                 message.complete(null);
                 return;
             }

Essentials/src/main/java/com/earth2me/essentials/commands/Commandinvsee.java

@@ -8,6 +8,8 @@ import org.bukkit.inventory.Inventory;
 import java.util.Collections;
 import java.util.List;
 
+import static com.earth2me.essentials.I18n.tl;
+
 public class Commandinvsee extends EssentialsCommand {
     public Commandinvsee() {
         super("invsee");
@@ -21,6 +23,11 @@ public class Commandinvsee extends EssentialsCommand {
         }
 
         final User invUser = getPlayer(server, user, args, 0);
+        if (user == invUser) {
+            user.sendMessage(tl("invseeNoSelf"));
+            throw new NoChargeException();
+        }
+
         final Inventory inv;
 
         if (args.length > 1 && user.isAuthorized("essentials.invsee.equip")) {
@@ -40,7 +47,9 @@ public class Commandinvsee extends EssentialsCommand {
     @Override
     protected List<String> getTabCompleteOptions(final Server server, final User user, final String commandLabel, final String[] args) {
         if (args.length == 1) {
-            return getPlayers(server, user);
+            final List<String> suggestions = getPlayers(server, user);
+            suggestions.remove(user.getName());
+            return suggestions;
         } else {
             //if (args.length == 2) {
             //    return Lists.newArrayList("equipped");

Essentials/src/main/java/com/earth2me/essentials/commands/Commanditem.java

@@ -2,7 +2,7 @@ package com.earth2me.essentials.commands;
 
 import com.earth2me.essentials.MetaItemStack;
 import com.earth2me.essentials.User;
-import com.earth2me.essentials.craftbukkit.InventoryWorkaround;
+import com.earth2me.essentials.craftbukkit.Inventories;
 import com.google.common.collect.Lists;
 import org.bukkit.Material;
 import org.bukkit.Server;
@@ -63,11 +63,7 @@ public class Commanditem extends EssentialsCommand {
 
         final String displayName = stack.getType().toString().toLowerCase(Locale.ENGLISH).replace('_', ' ');
         user.sendMessage(tl("itemSpawn", stack.getAmount(), displayName));
-        if (user.isAuthorized("essentials.oversizedstacks")) {
-            InventoryWorkaround.addOversizedItems(user.getBase().getInventory(), ess.getSettings().getOversizedStackSize(), stack);
-        } else {
-            InventoryWorkaround.addItems(user.getBase().getInventory(), stack);
-        }
+        Inventories.addItem(user.getBase(), user.isAuthorized("essentials.oversizedstacks") ? ess.getSettings().getOversizedStackSize() : 0, stack);
         user.getBase().updateInventory();
     }
 

Essentials/src/main/java/com/earth2me/essentials/commands/Commanditemlore.java

@@ -1,6 +1,7 @@
 package com.earth2me.essentials.commands;
 
 import com.earth2me.essentials.User;
+import com.earth2me.essentials.craftbukkit.Inventories;
 import com.earth2me.essentials.utils.FormatUtil;
 import com.earth2me.essentials.utils.MaterialUtil;
 import com.earth2me.essentials.utils.NumberUtil;
@@ -24,8 +25,8 @@ public class Commanditemlore extends EssentialsCommand {
 
     @Override
     protected void run(final Server server, final User user, final String commandLabel, final String[] args) throws Exception {
-        final ItemStack item = user.getBase().getItemInHand();
-        if (MaterialUtil.isAir(item.getType())) {
+        final ItemStack item = Inventories.getItemInHand(user.getBase());
+        if (item == null || MaterialUtil.isAir(item.getType())) {
             throw new Exception(tl("itemloreInvalidItem"));
         }
 
@@ -73,8 +74,8 @@ public class Commanditemlore extends EssentialsCommand {
         } else if (args.length == 2) {
             switch (args[0].toLowerCase(Locale.ENGLISH)) {
                 case "set": {
-                    final ItemStack item = user.getBase().getItemInHand();
-                    if (!MaterialUtil.isAir(item.getType()) && item.hasItemMeta() && item.getItemMeta().hasLore()) {
+                    final ItemStack item = Inventories.getItemInHand(user.getBase());
+                    if (item != null && !MaterialUtil.isAir(item.getType()) && item.hasItemMeta() && item.getItemMeta().hasLore()) {
                         final List<String> lineNumbers = new ArrayList<>();
                         for (int i = 1; i <= item.getItemMeta().getLore().size(); i++) {
                             lineNumbers.add(String.valueOf(i));
@@ -92,8 +93,8 @@ public class Commanditemlore extends EssentialsCommand {
         } else if (args.length == 3) {
             if (args[0].equalsIgnoreCase("set") && NumberUtil.isInt(args[1])) {
                 final int i = Integer.parseInt(args[1]);
-                final ItemStack item = user.getBase().getItemInHand();
-                if (!MaterialUtil.isAir(item.getType()) && item.hasItemMeta() && item.getItemMeta().hasLore() && item.getItemMeta().getLore().size() >= i) {
+                final ItemStack item = Inventories.getItemInHand(user.getBase());
+                if (item != null && !MaterialUtil.isAir(item.getType()) && item.hasItemMeta() && item.getItemMeta().hasLore() && item.getItemMeta().getLore().size() >= i) {
                     return Lists.newArrayList(FormatUtil.unformatString(user, "essentials.itemlore", item.getItemMeta().getLore().get(i - 1)));
                 }
             }

Essentials/src/main/java/com/earth2me/essentials/commands/Commanditemname.java

@@ -1,6 +1,7 @@
 package com.earth2me.essentials.commands;
 
 import com.earth2me.essentials.User;
+import com.earth2me.essentials.craftbukkit.Inventories;
 import com.earth2me.essentials.utils.FormatUtil;
 import com.earth2me.essentials.utils.MaterialUtil;
 import com.earth2me.essentials.utils.TriState;
@@ -23,8 +24,8 @@ public class Commanditemname extends EssentialsCommand {
 
     @Override
     protected void run(final Server server, final User user, final String commandLabel, final String[] args) throws Exception {
-        final ItemStack item = user.getBase().getItemInHand();
-        if (MaterialUtil.isAir(item.getType())) {
+        final ItemStack item = Inventories.getItemInHand(user.getBase());
+        if (item == null || MaterialUtil.isAir(item.getType())) {
             user.sendMessage(tl("itemnameInvalidItem"));
             return;
         }
@@ -50,8 +51,8 @@ public class Commanditemname extends EssentialsCommand {
     @Override
     protected List<String> getTabCompleteOptions(Server server, User user, String commandLabel, String[] args) {
         if (args.length == 1) {
-            final ItemStack item = user.getBase().getItemInHand();
-            if (!MaterialUtil.isAir(item.getType()) && item.hasItemMeta() && item.getItemMeta().hasDisplayName()) {
+            final ItemStack item = Inventories.getItemInHand(user.getBase());
+            if (item != null && !MaterialUtil.isAir(item.getType()) && item.hasItemMeta() && item.getItemMeta().hasDisplayName()) {
                 return Lists.newArrayList(FormatUtil.unformatString(user, "essentials.itemname", item.getItemMeta().getDisplayName()));
             }
         }

Essentials/src/main/java/com/earth2me/essentials/commands/Commandkick.java

@@ -28,7 +28,7 @@ public class Commandkick extends EssentialsCommand {
         final User user = sender.isPlayer() ? ess.getUser(sender.getPlayer()) : null;
 
         if (user != null) {
-            if (target.isHidden(sender.getPlayer()) && !user.canInteractVanished() && !sender.getPlayer().canSee(target.getBase())) {
+            if (target.isHidden(sender.getPlayer()) && !user.canInteractVanished() && target.isHiddenFrom(sender.getPlayer())) {
                 throw new PlayerNotFoundException();
             }
 
@@ -51,7 +51,7 @@ public class Commandkick extends EssentialsCommand {
         target.getBase().kickPlayer(kickReason);
         final String senderDisplayName = sender.isPlayer() ? sender.getPlayer().getDisplayName() : Console.DISPLAY_NAME;
 
-        server.getLogger().log(Level.INFO, tl("playerKicked", senderDisplayName, target.getName(), kickReason));
+        ess.getLogger().log(Level.INFO, tl("playerKicked", senderDisplayName, target.getName(), kickReason));
         ess.broadcastMessage("essentials.kick.notify", tl("playerKicked", senderDisplayName, target.getName(), kickReason));
     }
 

Essentials/src/main/java/com/earth2me/essentials/commands/Commandmail.java

@@ -261,8 +261,8 @@ public class Commandmail extends EssentialsCommand {
 
         @Override
         public void run() {
-            for (UUID userid : ess.getUserMap().getAllUniqueUsers()) {
-                final User user = ess.getUserMap().getUser(userid);
+            for (final UUID u : ess.getUsers().getAllUserUUIDs()) {
+                final User user = ess.getUsers().loadUncachedUser(u);
                 if (user != null) {
                     user.sendMail(messageRecipient, message, dateDiff);
                 }
@@ -298,9 +298,21 @@ public class Commandmail extends EssentialsCommand {
                 if (pages == 0) {
                     return Lists.newArrayList("0");
                 } else {
-                    final List<String> options = Lists.newArrayList("1");
-                    if (pages > 1) {
-                        options.add(String.valueOf(pages));
+                    final List<String> options = new ArrayList<>();
+                    for (int i = 0; i < pages; i++) {
+                        options.add(String.valueOf(i + 1));
+                    }
+                    return options;
+                }
+            } else if (args[0].equalsIgnoreCase("clear")) {
+                final ArrayList<MailMessage> mail = user.getMailMessages();
+                // We show up to 9 mails on a page, we don't need to autocomplete more than that...
+                if (mail.size() >= 9) {
+                    return Lists.newArrayList("1", "2", "3", "4", "5", "6", "7", "8", "9");
+                } else {
+                    final List<String> options = new ArrayList<>();
+                    for (int i = 0; i < mail.size(); i++) {
+                        options.add(String.valueOf(i + 1));
                     }
                     return options;
                 }

Essentials/src/main/java/com/earth2me/essentials/commands/Commandmute.java

@@ -1,7 +1,7 @@
 package com.earth2me.essentials.commands;
 
 import com.earth2me.essentials.CommandSource;
-import com.earth2me.essentials.OfflinePlayer;
+import com.earth2me.essentials.OfflinePlayerStub;
 import com.earth2me.essentials.User;
 import com.earth2me.essentials.utils.DateUtil;
 import net.ess3.api.events.MuteStatusChangeEvent;
@@ -29,7 +29,7 @@ public class Commandmute extends EssentialsCommand {
             user = getPlayer(server, args, 0, true, true);
         } catch (final PlayerNotFoundException e) {
             nomatch = true;
-            user = ess.getUser(new OfflinePlayer(args[0], ess.getServer()));
+            user = ess.getUser(new OfflinePlayerStub(args[0], ess.getServer()));
         }
         if (!user.getBase().isOnline() && sender.isPlayer()) {
             if (!sender.isAuthorized("essentials.mute.offline", ess)) {
@@ -113,7 +113,7 @@ public class Commandmute extends EssentialsCommand {
                         message = tl("muteNotifyReason", sender.getSender().getName(), user.getName(), user.getMuteReason());
                     }
                 }
-                server.getLogger().log(Level.INFO, message);
+                ess.getLogger().log(Level.INFO, message);
                 ess.broadcastMessage("essentials.mute.notify", message);
             } else {
                 sender.sendMessage(tl("unmutedPlayer", user.getDisplayName()));

Essentials/src/main/java/com/earth2me/essentials/commands/Commandnear.java

@@ -87,7 +87,7 @@ public class Commandnear extends EssentialsCommand {
         final Queue<User> nearbyPlayers = new PriorityQueue<>((o1, o2) -> (int) (o1.getLocation().distanceSquared(loc) - o2.getLocation().distanceSquared(loc)));
 
         for (final User player : ess.getOnlineUsers()) {
-            if (!player.equals(user) && !player.isAuthorized("essentials.near.exclude") && (!player.isHidden(user.getBase()) || showHidden || user.getBase().canSee(player.getBase()))) {
+            if (!player.equals(user) && !player.isAuthorized("essentials.near.exclude") && (!player.isHidden(user.getBase()) || showHidden || !player.isHiddenFrom(user.getBase()))) {
                 final Location playerLoc = player.getLocation();
                 if (playerLoc.getWorld() != world) {
                     continue;

Essentials/src/main/java/com/earth2me/essentials/commands/Commandnuke.java

@@ -6,6 +6,7 @@ import org.bukkit.Server;
 import org.bukkit.World;
 import org.bukkit.entity.Player;
 import org.bukkit.entity.TNTPrimed;
+import org.bukkit.metadata.FixedMetadataValue;
 
 import java.util.ArrayList;
 import java.util.Collection;
@@ -15,6 +16,9 @@ import java.util.List;
 import static com.earth2me.essentials.I18n.tl;
 
 public class Commandnuke extends EssentialsCommand {
+
+    public static final String NUKE_META_KEY = "ess_tnt_proj";
+
     public Commandnuke() {
         super("nuke");
     }
@@ -30,7 +34,6 @@ public class Commandnuke extends EssentialsCommand {
         } else {
             targets = ess.getOnlinePlayers();
         }
-        ess.getTNTListener().enable();
         for (final Player player : targets) {
             if (player == null) {
                 continue;
@@ -38,9 +41,12 @@ public class Commandnuke extends EssentialsCommand {
             player.sendMessage(tl("nuke"));
             final Location loc = player.getLocation();
             final World world = loc.getWorld();
-            for (int x = -10; x <= 10; x += 5) {
-                for (int z = -10; z <= 10; z += 5) {
-                    world.spawn(new Location(world, loc.getBlockX() + x, world.getHighestBlockYAt(loc) + 64, loc.getBlockZ() + z), TNTPrimed.class);
+            if (world != null) {
+                for (int x = -10; x <= 10; x += 5) {
+                    for (int z = -10; z <= 10; z += 5) {
+                        final TNTPrimed entity = world.spawn(new Location(world, loc.getBlockX() + x, world.getHighestBlockYAt(loc) + 64, loc.getBlockZ() + z), TNTPrimed.class);
+                        entity.setMetadata(NUKE_META_KEY, new FixedMetadataValue(ess, true));
+                    }
                 }
             }
         }

Essentials/src/main/java/com/earth2me/essentials/commands/Commandpowertool.java

@@ -2,6 +2,7 @@ package com.earth2me.essentials.commands;
 
 import com.earth2me.essentials.CommandSource;
 import com.earth2me.essentials.User;
+import com.earth2me.essentials.craftbukkit.Inventories;
 import com.earth2me.essentials.utils.StringUtil;
 import com.google.common.collect.Lists;
 import org.bukkit.Material;
@@ -22,7 +23,7 @@ public class Commandpowertool extends EssentialsCommand {
     @Override
     protected void run(final Server server, final User user, final String commandLabel, final String[] args) throws Exception {
         final String command = getFinalArg(args, 0);
-        final ItemStack itemStack = user.getBase().getItemInHand();
+        final ItemStack itemStack = Inventories.getItemInHand(user.getBase());
         powertool(user.getSource(), user, itemStack, command);
     }
 
@@ -111,7 +112,7 @@ public class Commandpowertool extends EssentialsCommand {
             }
 
             try {
-                final ItemStack itemStack = user.getBase().getItemInHand();
+                final ItemStack itemStack = Inventories.getItemInHand(user.getBase());
                 final List<String> powertools = user.getPowertool(itemStack);
                 for (final String tool : powertools) {
                     options.add("r:" + tool);

Essentials/src/main/java/com/earth2me/essentials/commands/Commandrealname.java

@@ -25,7 +25,7 @@ public class Commandrealname extends EssentialsCommand {
         final boolean skipHidden = sender.isPlayer() && !ess.getUser(sender.getPlayer()).canInteractVanished();
         boolean foundUser = false;
         for (final User u : ess.getOnlineUsers()) {
-            if (skipHidden && u.isHidden(sender.getPlayer()) && !sender.getPlayer().canSee(u.getBase())) {
+            if (skipHidden && u.isHidden(sender.getPlayer()) && u.isHiddenFrom(sender.getPlayer())) {
                 continue;
             }
             u.setDisplayNick();

Essentials/src/main/java/com/earth2me/essentials/commands/Commandrecipe.java

@@ -2,6 +2,7 @@ package com.earth2me.essentials.commands;
 
 import com.earth2me.essentials.CommandSource;
 import com.earth2me.essentials.User;
+import com.earth2me.essentials.craftbukkit.Inventories;
 import com.earth2me.essentials.utils.EnumUtil;
 import com.earth2me.essentials.utils.NumberUtil;
 import com.earth2me.essentials.utils.VersionUtil;
@@ -53,7 +54,18 @@ public class Commandrecipe extends EssentialsCommand {
             throw new NotEnoughArgumentsException();
         }
 
-        final ItemStack itemType = ess.getItemDb().get(args[0]);
+        final ItemStack itemType;
+
+        if (args[0].equalsIgnoreCase("hand")) {
+            if (!sender.isPlayer()) {
+                throw new Exception(tl("consoleCannotUseCommand"));
+            }
+            
+            itemType = Inventories.getItemInHand(sender.getPlayer());
+        } else {
+            itemType = ess.getItemDb().get(args[0]);
+        }
+
         int recipeNo = 0;
 
         if (args.length > 1) {
@@ -155,6 +167,7 @@ public class Commandrecipe extends EssentialsCommand {
         final List<ItemStack> ingredients = recipe.getIngredientList();
         if (showWindow) {
             final User user = ess.getUser(sender.getPlayer());
+            user.getBase().closeInventory();
             user.setRecipeSee(true);
             final InventoryView view = user.getBase().openWorkbench(null, true);
             for (int i = 0; i < ingredients.size(); i++) {

Essentials/src/main/java/com/earth2me/essentials/commands/Commandrenamehome.java

@@ -0,0 +1,107 @@
+package com.earth2me.essentials.commands;
+
+import com.earth2me.essentials.CommandSource;
+import com.earth2me.essentials.User;
+import com.earth2me.essentials.utils.NumberUtil;
+import net.ess3.api.IUser;
+import net.essentialsx.api.v2.events.HomeModifyEvent;
+import org.bukkit.Bukkit;
+import org.bukkit.Server;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.Locale;
+
+import static com.earth2me.essentials.I18n.tl;
+
+public class Commandrenamehome extends EssentialsCommand {
+    public Commandrenamehome() {
+        super("renamehome");
+    }
+
+    @Override
+    public void run(final Server server, final User user, final String commandLabel, final String[] args) throws Exception {
+        User usersHome = user;
+        final String oldName;
+        final String newName;
+
+        // Allowing both formats /renamehome jroy home1 home | /sethome jroy:home1 home
+        if (args.length == 2) {
+            final String[] nameParts = args[0].split(":", 2);
+            newName = args[1].toLowerCase(Locale.ENGLISH);
+
+            if (nameParts.length == 2) {
+                oldName = nameParts[1].toLowerCase(Locale.ENGLISH);
+                if (user.isAuthorized("essentials.renamehome.others")) {
+                    usersHome = getPlayer(server, nameParts[0], true, true);
+                    if (usersHome == null) {
+                        throw new PlayerNotFoundException();
+                    }
+                }
+            } else {
+                oldName = args[0].toLowerCase(Locale.ENGLISH);
+            }
+        } else if (args.length == 3) {
+            if (!user.isAuthorized("essentials.renamehome.others")) {
+                throw new NotEnoughArgumentsException();
+            }
+
+            usersHome = getPlayer(server, args[0], true, true);
+            if (usersHome == null) {
+                throw new PlayerNotFoundException();
+            }
+
+            oldName = args[1].toLowerCase(Locale.ENGLISH);
+            newName = args[2].toLowerCase(Locale.ENGLISH);
+        } else {
+            throw new NotEnoughArgumentsException();
+        }
+
+        if ("bed".equals(newName) || NumberUtil.isInt(newName) || "bed".equals(oldName) || NumberUtil.isInt(oldName)) {
+            throw new NoSuchFieldException(tl("invalidHomeName"));
+        }
+
+        final HomeModifyEvent event = new HomeModifyEvent(user, usersHome, oldName, newName, usersHome.getHome(oldName));
+        Bukkit.getServer().getPluginManager().callEvent(event);
+        if (event.isCancelled()) {
+            if (ess.getSettings().isDebug()) {
+                ess.getLogger().info("HomeModifyEvent canceled for /renamehome execution by " + user.getDisplayName());
+            }
+            return;
+        }
+
+        usersHome.renameHome(oldName, newName);
+        user.sendMessage(tl("homeRenamed", oldName, newName));
+        usersHome.setLastHomeConfirmation(null);
+
+    }
+
+    @Override
+    protected List<String> getTabCompleteOptions(final Server server, final CommandSource sender, final String commandLabel, final String[] args) {
+        final IUser user = sender.getUser(ess);
+        if (args.length != 1) {
+            return Collections.emptyList();
+        }
+
+        final List<String> homes = user == null ? new ArrayList<>() : user.getHomes();
+        final boolean canRenameOthers = sender.isAuthorized("essentials.renamehome.others", ess);
+
+        if (canRenameOthers) {
+            final int sepIndex = args[0].indexOf(':');
+            if (sepIndex < 0) {
+                getPlayers(server, sender).forEach(player -> homes.add(player + ":"));
+            } else {
+                final String namePart = args[0].substring(0, sepIndex);
+                final User otherUser;
+                try {
+                    otherUser = getPlayer(server, new String[]{namePart}, 0, true, true);
+                } catch (final Exception ex) {
+                    return homes;
+                }
+                otherUser.getHomes().forEach(home -> homes.add(namePart + ":" + home));
+            }
+        }
+        return homes;
+    }
+}

Essentials/src/main/java/com/earth2me/essentials/commands/Commandrepair.java

@@ -3,6 +3,7 @@ package com.earth2me.essentials.commands;
 import com.earth2me.essentials.ChargeException;
 import com.earth2me.essentials.Trade;
 import com.earth2me.essentials.User;
+import com.earth2me.essentials.craftbukkit.Inventories;
 import com.earth2me.essentials.utils.MaterialUtil;
 import com.earth2me.essentials.utils.StringUtil;
 import com.earth2me.essentials.utils.VersionUtil;
@@ -62,7 +63,7 @@ public class Commandrepair extends EssentialsCommand {
 
     public void repairAll(final User user) throws Exception {
         final List<String> repaired = new ArrayList<>();
-        repairItems(user.getBase().getInventory().getContents(), user, repaired);
+        repairItems(Inventories.getInventory(user.getBase(), false), user, repaired);
 
         if (user.isAuthorized("essentials.repair.armor")) {
             repairItems(user.getBase().getInventory().getArmorContents(), user, repaired);

Essentials/src/main/java/com/earth2me/essentials/commands/Commandseen.java

@@ -2,7 +2,6 @@ package com.earth2me.essentials.commands;
 
 import com.earth2me.essentials.CommandSource;
 import com.earth2me.essentials.User;
-import com.earth2me.essentials.UserMap;
 import com.earth2me.essentials.craftbukkit.BanLookup;
 import com.earth2me.essentials.utils.DateUtil;
 import com.earth2me.essentials.utils.FormatUtil;
@@ -63,7 +62,7 @@ public class Commandseen extends EssentialsCommand {
             ess.getScheduler().runTaskAsynchronously(ess, new Runnable() {
                 @Override
                 public void run() {
-                    final User userFromBukkit = ess.getUserMap().getUserFromBukkit(args[0]);
+                    final User userFromBukkit = ess.getUsers().getUser(args[0]);
                     try {
                         if (userFromBukkit != null) {
                             showUserSeen(userFromBukkit);
@@ -103,8 +102,8 @@ public class Commandseen extends EssentialsCommand {
         user.setDisplayNick();
         sender.sendMessage(tl("seenOnline", user.getDisplayName(), DateUtil.formatDateDiff(user.getLastLogin())));
 
-        final List<String> history = ess.getUserMap().getUserHistory(user.getBase().getUniqueId());
-        if (history != null && history.size() > 1) {
+        final List<String> history = user.getPastUsernames();
+        if (history != null && !history.isEmpty()) {
             sender.sendMessage(tl("seenAccounts", StringUtil.joinListSkip(", ", user.getName(), history)));
         }
 
@@ -139,7 +138,7 @@ public class Commandseen extends EssentialsCommand {
         user.setDisplayNick();
         if (user.getLastLogout() > 0) {
             sender.sendMessage(tl("seenOffline", user.getName(), DateUtil.formatDateDiff(user.getLastLogout())));
-            final List<String> history = ess.getUserMap().getUserHistory(user.getBase().getUniqueId());
+            final List<String> history = user.getPastUsernames();
             if (history != null && history.size() > 1) {
                 sender.sendMessage(tl("seenAccounts", StringUtil.joinListSkip(", ", user.getName(), history)));
             }
@@ -192,14 +191,12 @@ public class Commandseen extends EssentialsCommand {
     }
 
     private void seenIP(final CommandSource sender, final String ipAddress, final String display) {
-        final UserMap userMap = ess.getUserMap();
-
         sender.sendMessage(tl("runningPlayerMatch", display));
 
         ess.runTaskAsynchronously(() -> {
             final List<String> matches = new ArrayList<>();
-            for (final UUID u : userMap.getAllUniqueUsers()) {
-                final User user = ess.getUserMap().getUser(u);
+            for (final UUID u : ess.getUsers().getAllUserUUIDs()) {
+                final User user = ess.getUsers().loadUncachedUser(u);
                 if (user == null) {
                     continue;
                 }

Essentials/src/main/java/com/earth2me/essentials/commands/Commandsell.java

@@ -2,6 +2,7 @@ package com.earth2me.essentials.commands;
 
 import com.earth2me.essentials.Trade;
 import com.earth2me.essentials.User;
+import com.earth2me.essentials.craftbukkit.Inventories;
 import com.earth2me.essentials.utils.NumberUtil;
 import com.google.common.collect.Lists;
 import net.ess3.api.events.UserBalanceUpdateEvent;
@@ -108,11 +109,11 @@ public class Commandsell extends EssentialsCommand {
         //TODO: Prices for Enchantments
         final ItemStack ris = is.clone();
         ris.setAmount(amount);
-        if (!user.getBase().getInventory().containsAtLeast(ris, amount)) {
+        if (!Inventories.containsAtLeast(user.getBase(), ris, amount)) {
             // This should never happen.
             throw new IllegalStateException("Trying to remove more items than are available.");
         }
-        user.getBase().getInventory().removeItem(ris);
+        Inventories.removeItemAmount(user.getBase(), ris, ris.getAmount());
         user.getBase().updateInventory();
         Trade.log("Command", "Sell", "Item", user.getName(), new Trade(ris, ess), user.getName(), new Trade(result, ess), user.getLocation(), user.getMoney(), ess);
         user.giveMoney(result, null, UserBalanceUpdateEvent.Cause.COMMAND_SELL);

Essentials/src/main/java/com/earth2me/essentials/commands/Commandsethome.java

@@ -4,6 +4,8 @@ import com.earth2me.essentials.CommandSource;
 import com.earth2me.essentials.User;
 import com.earth2me.essentials.utils.LocationUtil;
 import com.earth2me.essentials.utils.NumberUtil;
+import net.essentialsx.api.v2.events.HomeModifyEvent;
+import org.bukkit.Bukkit;
 import org.bukkit.Location;
 import org.bukkit.Server;
 
@@ -62,8 +64,25 @@ public class Commandsethome extends EssentialsCommand {
             return;
         }
 
+        final Location prevHomeLoc = usersHome.getHome(name);
+
+        final HomeModifyEvent event;
+        if (prevHomeLoc == null) {
+            event = new HomeModifyEvent(user, usersHome, name, location, true);
+        } else {
+            event = new HomeModifyEvent(user, usersHome, name, prevHomeLoc, location);
+        }
+
+        Bukkit.getServer().getPluginManager().callEvent(event);
+        if (event.isCancelled()) {
+            if (ess.getSettings().isDebug()) {
+                ess.getLogger().info("HomeModifyEvent canceled for /sethome execution by " + user.getDisplayName());
+            }
+            return;
+        }
+
         usersHome.setHome(name, location);
-        user.sendMessage(tl("homeSet", user.getLocation().getWorld().getName(), user.getLocation().getBlockX(), user.getLocation().getBlockY(), user.getLocation().getBlockZ(), name));
+        user.sendMessage(tl("homeSet", location.getWorld().getName(), location.getBlockX(), location.getBlockY(), location.getBlockZ(), name));
         usersHome.setLastHomeConfirmation(null);
 
     }

Essentials/src/main/java/com/earth2me/essentials/commands/Commandsetworth.java

@@ -22,7 +22,7 @@ public class Commandsetworth extends EssentialsCommand {
         final ItemStack stack;
         final String price;
         if (args.length == 1) {
-            stack = user.getBase().getInventory().getItemInHand();
+            stack = user.getItemInHand();
             price = args[0];
         } else {
             stack = ess.getItemDb().get(args[0]);

Essentials/src/main/java/com/earth2me/essentials/commands/Commandskull.java

@@ -1,7 +1,7 @@
 package com.earth2me.essentials.commands;
 
 import com.earth2me.essentials.User;
-import com.earth2me.essentials.craftbukkit.InventoryWorkaround;
+import com.earth2me.essentials.craftbukkit.Inventories;
 import com.earth2me.essentials.utils.EnumUtil;
 import com.earth2me.essentials.utils.MaterialUtil;
 import com.google.common.collect.Lists;
@@ -9,7 +9,6 @@ import org.bukkit.Material;
 import org.bukkit.Server;
 import org.bukkit.inventory.ItemStack;
 import org.bukkit.inventory.meta.SkullMeta;
-import org.bukkit.scheduler.BukkitRunnable;
 
 import java.util.Collections;
 import java.util.List;
@@ -60,26 +59,21 @@ public class Commandskull extends EssentialsCommand {
     }
 
     private void editSkull(final User user, final ItemStack stack, final SkullMeta skullMeta, final String owner, final boolean spawn) {
-        new BukkitRunnable() {
-            @Override
-            public void run() {
-                //Run this stuff async because SkullMeta#setOwner causes a http request.
-                skullMeta.setDisplayName("§fSkull of " + owner);
-                skullMeta.setOwner(owner);
-                new BukkitRunnable() {
-                    @Override
-                    public void run() {
-                        stack.setItemMeta(skullMeta);
-                        if (spawn) {
-                            InventoryWorkaround.addItems(user.getBase().getInventory(), stack);
-                            user.sendMessage(tl("givenSkull", owner));
-                            return;
-                        }
-                        user.sendMessage(tl("skullChanged", owner));
-                    }
-                }.runTask(ess);
-            }
-        }.runTaskAsynchronously(ess);
+        ess.runTaskAsynchronously(() -> {
+            //Run this stuff async because SkullMeta#setOwner causes a http request.
+            skullMeta.setDisplayName("§fSkull of " + owner);
+            //noinspection deprecation
+            skullMeta.setOwner(owner);
+            ess.scheduleSyncDelayedTask(() -> {
+                stack.setItemMeta(skullMeta);
+                if (spawn) {
+                    Inventories.addItem(user.getBase(), stack);
+                    user.sendMessage(tl("givenSkull", owner));
+                    return;
+                }
+                user.sendMessage(tl("skullChanged", owner));
+            });
+        });
     }
 
     @Override

Essentials/src/main/java/com/earth2me/essentials/commands/Commandspeed.java

@@ -67,7 +67,7 @@ public class Commandspeed extends EssentialsCommand {
         final List<Player> matchedPlayers = server.matchPlayer(name);
         for (final Player matchPlayer : matchedPlayers) {
             final User player = ess.getUser(matchPlayer);
-            if (skipHidden && player.isHidden(sender.getPlayer()) && !sender.getPlayer().canSee(matchPlayer)) {
+            if (skipHidden && player.isHidden(sender.getPlayer()) && player.isHiddenFrom(sender.getPlayer())) {
                 continue;
             }
             foundUser = true;

Essentials/src/main/java/com/earth2me/essentials/commands/Commandtempban.java

@@ -54,7 +54,7 @@ public class Commandtempban extends EssentialsCommand {
         user.getBase().kickPlayer(tl("tempBanned", expiry, senderDisplayName, banReason));
 
         final String message = tl("playerTempBanned", senderDisplayName, user.getName(), expiry, banReason);
-        server.getLogger().log(Level.INFO, message);
+        ess.getLogger().log(Level.INFO, message);
         ess.broadcastMessage("essentials.ban.notify", message);
     }
 

Essentials/src/main/java/com/earth2me/essentials/commands/Commandtempbanip.java

@@ -71,7 +71,7 @@ public class Commandtempbanip extends EssentialsCommand {
 
         final String message = tl("playerTempBanIpAddress", senderDisplayName, ipAddress,
                 DateUtil.formatDateDiff(banTimestamp), banReason);
-        server.getLogger().log(Level.INFO, message);
+        ess.getLogger().log(Level.INFO, message);
         ess.broadcastMessage("essentials.banip.notify", message);
     }
 

Essentials/src/main/java/com/earth2me/essentials/commands/Commandtogglejail.java

@@ -87,7 +87,7 @@ public class Commandtogglejail extends EssentialsCommand {
                         sender.sendMessage(timeDiff > 0 ? tl("playerJailedFor", player.getName(), DateUtil.formatDateDiff(finalDisplayTime)) : tl("playerJailed", player.getName()));
 
                         final String notifyMessage = timeDiff > 0 ? tl("jailNotifyJailedFor", player.getName(), DateUtil.formatDateDiff(finalDisplayTime), sender.getSender().getName()) : tl("jailNotifyJailed", player.getName(), sender.getSender().getName());
-                        server.getLogger().log(Level.INFO, notifyMessage);
+                        ess.getLogger().log(Level.INFO, notifyMessage);
                         ess.broadcastMessage("essentials.jail.notify", notifyMessage);
                     }
                 });
@@ -114,7 +114,7 @@ public class Commandtogglejail extends EssentialsCommand {
             sender.sendMessage(tl("jailSentenceExtended", DateUtil.formatDateDiff(displayTimeDiff)));
 
             final String notifyMessage = tl("jailNotifySentenceExtended", player.getName(), DateUtil.formatDateDiff(displayTimeDiff), sender.getSender().getName());
-            server.getLogger().log(Level.INFO, notifyMessage);
+            ess.getLogger().log(Level.INFO, notifyMessage);
             ess.broadcastMessage("essentials.jail.notify", notifyMessage);
             return;
         }

Essentials/src/main/java/com/earth2me/essentials/commands/Commandtop.java

@@ -24,12 +24,12 @@ public class Commandtop extends EssentialsCommand {
         final float yaw = user.getLocation().getYaw();
         final Location unsafe = new Location(user.getWorld(), topX, ess.getWorldInfoProvider().getMaxHeight(user.getWorld()), topZ, yaw, pitch);
         final Location safe = LocationUtil.getSafeDestination(ess, unsafe);
-        final CompletableFuture<Boolean> future = new CompletableFuture<>();
+        final CompletableFuture<Boolean> future = getNewExceptionFuture(user.getSource(), commandLabel);
         future.thenAccept(success -> {
             if (success) {
                 user.sendMessage(tl("teleportTop", safe.getWorld().getName(), safe.getBlockX(), safe.getBlockY(), safe.getBlockZ()));
             }
         });
-        user.getAsyncTeleport().teleport(safe, new Trade(this.getName(), ess), TeleportCause.COMMAND, getNewExceptionFuture(user.getSource(), commandLabel));
+        user.getAsyncTeleport().teleport(safe, new Trade(this.getName(), ess), TeleportCause.COMMAND, future);
     }
 }

Essentials/src/main/java/com/earth2me/essentials/commands/Commandtpoffline.java

@@ -21,6 +21,11 @@ public class Commandtpoffline extends EssentialsCommand {
             final User target = getPlayer(server, args, 0, true, true);
             final Location logout = target.getLogoutLocation();
 
+            if (logout == null) {
+                user.sendMessage(tl("teleportOfflineUnknown", user.getDisplayName()));
+                throw new NoChargeException();
+            }
+
             if (user.getWorld() != logout.getWorld() && ess.getSettings().isWorldTeleportPermissions() && !user.isAuthorized("essentials.worlds." + logout.getWorld().getName())) {
                 throw new Exception(tl("noPerm", "essentials.worlds." + logout.getWorld().getName()));
             }

Essentials/src/main/java/com/earth2me/essentials/commands/Commandtppos.java

@@ -66,9 +66,9 @@ public class Commandtppos extends EssentialsCommand {
         }
 
         final User user = getPlayer(server, args, 0, true, false);
-        final double x = args[1].startsWith("~") ? user.getLocation().getX() + (args[1].length() > 1 ? Integer.parseInt(args[1].substring(1)) : 0) : Integer.parseInt(args[1]);
-        final double y = args[2].startsWith("~") ? user.getLocation().getY() + (args[2].length() > 1 ? Integer.parseInt(args[2].substring(1)) : 0) : Integer.parseInt(args[2]);
-        final double z = args[3].startsWith("~") ? user.getLocation().getZ() + (args[3].length() > 1 ? Integer.parseInt(args[3].substring(1)) : 0) : Integer.parseInt(args[3]);
+        final double x = args[1].startsWith("~") ? user.getLocation().getX() + (args[1].length() > 1 ? Double.parseDouble(args[1].substring(1)) : 0) : Double.parseDouble(args[1]);
+        final double y = args[2].startsWith("~") ? user.getLocation().getY() + (args[2].length() > 1 ? Double.parseDouble(args[2].substring(1)) : 0) : Double.parseDouble(args[2]);
+        final double z = args[3].startsWith("~") ? user.getLocation().getZ() + (args[3].length() > 1 ? Double.parseDouble(args[3].substring(1)) : 0) : Double.parseDouble(args[3]);
         final Location loc = new Location(user.getWorld(), x, y, z, user.getLocation().getYaw(), user.getLocation().getPitch());
         if (args.length == 5) {
             loc.setWorld(ess.getWorld(args[4]));

Essentials/src/main/java/com/earth2me/essentials/commands/Commandunban.java

@@ -37,7 +37,7 @@ public class Commandunban extends EssentialsCommand {
         }
 
         final String senderDisplayName = sender.isPlayer() ? sender.getPlayer().getDisplayName() : Console.DISPLAY_NAME;
-        server.getLogger().log(Level.INFO, tl("playerUnbanned", senderDisplayName, name));
+        ess.getLogger().log(Level.INFO, tl("playerUnbanned", senderDisplayName, name));
 
         ess.broadcastMessage("essentials.ban.notify", tl("playerUnbanned", senderDisplayName, name));
     }

Essentials/src/main/java/com/earth2me/essentials/commands/Commandunbanip.java

@@ -40,7 +40,7 @@ public class Commandunbanip extends EssentialsCommand {
 
         ess.getServer().getBanList(BanList.Type.IP).pardon(ipAddress);
         final String senderDisplayName = sender.isPlayer() ? sender.getPlayer().getDisplayName() : Console.DISPLAY_NAME;
-        server.getLogger().log(Level.INFO, tl("playerUnbanIpAddress", senderDisplayName, ipAddress));
+        ess.getLogger().log(Level.INFO, tl("playerUnbanIpAddress", senderDisplayName, ipAddress));
 
         ess.broadcastMessage("essentials.banip.notify", tl("playerUnbanIpAddress", senderDisplayName, ipAddress));
     }

Essentials/src/main/java/com/earth2me/essentials/commands/Commandunlimited.java

@@ -1,6 +1,7 @@
 package com.earth2me.essentials.commands;
 
 import com.earth2me.essentials.User;
+import com.earth2me.essentials.craftbukkit.Inventories;
 import org.bukkit.Material;
 import org.bukkit.Server;
 import org.bukkit.inventory.ItemStack;
@@ -75,8 +76,8 @@ public class Commandunlimited extends EssentialsCommand {
         if (!target.hasUnlimited(stack)) {
             message = "enableUnlimited";
             enableUnlimited = true;
-            if (!target.getBase().getInventory().containsAtLeast(stack, stack.getAmount())) {
-                target.getBase().getInventory().addItem(stack);
+            if (!Inventories.containsAtLeast(target.getBase(), stack, stack.getAmount())) {
+                Inventories.addItem(target.getBase(), stack);
             }
         }
 

Essentials/src/main/java/com/earth2me/essentials/commands/Commandwhois.java

@@ -40,7 +40,7 @@ public class Commandwhois extends EssentialsCommand {
         sender.sendMessage(tl("whoisHunger", user.getBase().getFoodLevel(), user.getBase().getSaturation()));
         sender.sendMessage(tl("whoisExp", SetExpFix.getTotalExperience(user.getBase()), user.getBase().getLevel()));
         sender.sendMessage(tl("whoisLocation", user.getLocation().getWorld().getName(), user.getLocation().getBlockX(), user.getLocation().getBlockY(), user.getLocation().getBlockZ()));
-        final long playtimeMs = System.currentTimeMillis() - (user.getBase().getStatistic(PLAY_ONE_TICK) * 50);
+        final long playtimeMs = System.currentTimeMillis() - (user.getBase().getStatistic(PLAY_ONE_TICK) * 50L);
         sender.sendMessage(tl("whoisPlaytime", DateUtil.formatDateDiff(playtimeMs)));
         if (!ess.getSettings().isEcoDisabled()) {
             sender.sendMessage(tl("whoisMoney", NumberUtil.displayCurrency(user.getMoney(), ess)));

Essentials/src/main/java/com/earth2me/essentials/commands/EssentialsLoopCommand.java

@@ -30,16 +30,21 @@ public abstract class EssentialsLoopCommand extends EssentialsCommand {
         final UUID uuid = StringUtil.toUUID(searchTerm);
         if (uuid != null) {
             final User matchedUser = ess.getUser(uuid);
+            if (matchedUser == null) {
+                throw new PlayerNotFoundException();
+            }
             userConsumer.accept(matchedUser);
         } else if (matchWildcards && searchTerm.contentEquals("**")) {
-            for (final UUID sUser : ess.getUserMap().getAllUniqueUsers()) {
-                final User matchedUser = ess.getUser(sUser);
-                userConsumer.accept(matchedUser);
+            for (final UUID u : ess.getUsers().getAllUserUUIDs()) {
+                final User user = ess.getUsers().loadUncachedUser(u);
+                if (user != null) {
+                    userConsumer.accept(user);
+                }
             }
         } else if (matchWildcards && searchTerm.contentEquals("*")) {
             final boolean skipHidden = sender.isPlayer() && !ess.getUser(sender.getPlayer()).canInteractVanished();
             for (final User onlineUser : ess.getOnlineUsers()) {
-                if (skipHidden && onlineUser.isHidden(sender.getPlayer()) && !sender.getPlayer().canSee(onlineUser.getBase())) {
+                if (skipHidden && onlineUser.isHidden(sender.getPlayer()) && onlineUser.isHiddenFrom(sender.getPlayer())) {
                     continue;
                 }
                 userConsumer.accept(onlineUser);
@@ -76,7 +81,7 @@ public abstract class EssentialsLoopCommand extends EssentialsCommand {
 
         if (matchWildcards && (searchTerm.contentEquals("**") || searchTerm.contentEquals("*"))) {
             for (final User onlineUser : ess.getOnlineUsers()) {
-                if (skipHidden && onlineUser.isHidden(sender.getPlayer()) && !sender.getPlayer().canSee(onlineUser.getBase())) {
+                if (skipHidden && onlineUser.isHidden(sender.getPlayer()) && onlineUser.isHiddenFrom(sender.getPlayer())) {
                     continue;
                 }
                 userConsumer.accept(onlineUser);
@@ -91,7 +96,7 @@ public abstract class EssentialsLoopCommand extends EssentialsCommand {
             if (matchedPlayers.isEmpty()) {
                 final String matchText = searchTerm.toLowerCase(Locale.ENGLISH);
                 for (final User player : ess.getOnlineUsers()) {
-                    if (skipHidden && player.isHidden(sender.getPlayer()) && !sender.getPlayer().canSee(player.getBase())) {
+                    if (skipHidden && player.isHidden(sender.getPlayer()) && player.isHiddenFrom(sender.getPlayer())) {
                         continue;
                     }
                     final String displayName = FormatUtil.stripFormat(player.getDisplayName()).toLowerCase(Locale.ENGLISH);
@@ -103,7 +108,7 @@ public abstract class EssentialsLoopCommand extends EssentialsCommand {
             } else {
                 for (final Player matchPlayer : matchedPlayers) {
                     final User player = ess.getUser(matchPlayer);
-                    if (skipHidden && player.isHidden(sender.getPlayer()) && !sender.getPlayer().canSee(matchPlayer)) {
+                    if (skipHidden && player.isHidden(sender.getPlayer()) && player.isHiddenFrom(sender.getPlayer())) {
                         continue;
                     }
                     foundUser = true;

Essentials/src/main/java/com/earth2me/essentials/commands/EssentialsToggleCommand.java

@@ -51,7 +51,7 @@ public abstract class EssentialsToggleCommand extends EssentialsCommand {
         final List<Player> matchedPlayers = server.matchPlayer(args[0]);
         for (final Player matchPlayer : matchedPlayers) {
             final User player = ess.getUser(matchPlayer);
-            if (skipHidden && player.isHidden(sender.getPlayer()) && !sender.getPlayer().canSee(matchPlayer)) {
+            if (skipHidden && player.isHidden(sender.getPlayer()) && player.isHiddenFrom(sender.getPlayer())) {
                 continue;
             }
             foundUser = true;

Essentials/src/main/java/com/earth2me/essentials/config/EssentialsConfiguration.java

@@ -33,7 +33,9 @@ import java.lang.reflect.Type;
 import java.math.BigDecimal;
 import java.nio.file.Files;
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.HashMap;
+import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Locale;
 import java.util.Map;
@@ -103,6 +105,15 @@ public class EssentialsConfiguration {
         return configurationNode;
     }
 
+    public void setRootHolder(final Class<?> holderClass, final Object holder) {
+        try {
+            getRootNode().set(holderClass, holder);
+        } catch (SerializationException e) {
+            Essentials.getWrappedLogger().log(Level.SEVERE, "Error while saving user config: " + configFile.getName(), e);
+            throw new RuntimeException(e);
+        }
+    }
+
     public File getFile() {
         return configFile;
     }
@@ -120,6 +131,7 @@ public class EssentialsConfiguration {
         try {
             return node.get(LazyLocation.class);
         } catch (SerializationException e) {
+            Essentials.getWrappedLogger().log(Level.SEVERE, e.getMessage(), e);
             return null;
         }
     }
@@ -261,7 +273,8 @@ public class EssentialsConfiguration {
         try {
             return node.get(BigDecimal.class);
         } catch (SerializationException e) {
-            return null;
+            Essentials.getWrappedLogger().log(Level.SEVERE, e.getMessage(), e);
+            return def;
         }
     }
 
@@ -294,6 +307,19 @@ public class EssentialsConfiguration {
         return ConfigurateUtil.getMap(configurationNode);
     }
 
+    public Map<String, String> getStringMap(String path) {
+        final CommentedConfigurationNode node = getInternal(path);
+        if (node == null || !node.isMap()) {
+            return Collections.emptyMap();
+        }
+
+        final Map<String, String> map = new LinkedHashMap<>();
+        for (Map.Entry<Object, CommentedConfigurationNode> entry : node.childrenMap().entrySet()) {
+            map.put(String.valueOf(entry.getKey()), String.valueOf(entry.getValue().rawScalar()));
+        }
+        return map;
+    }
+
     public void removeProperty(String path) {
         final CommentedConfigurationNode node = getInternal(path);
         if (node != null) {
@@ -366,10 +392,10 @@ public class EssentialsConfiguration {
         } catch (final ParsingException e) {
             final File broken = new File(configFile.getAbsolutePath() + ".broken." + System.currentTimeMillis());
             if (configFile.renameTo(broken)) {
-                Essentials.getWrappedLogger().log(Level.SEVERE, "The file " + configFile.toString() + " is broken, it has been renamed to " + broken.toString(), e.getCause());
+                Essentials.getWrappedLogger().log(Level.SEVERE, "The file " + configFile + " is broken, it has been renamed to " + broken, e.getCause());
                 return;
             }
-            Essentials.getWrappedLogger().log(Level.SEVERE, "The file " + configFile.toString() + " is broken. A backup file has failed to be created", e.getCause());
+            Essentials.getWrappedLogger().log(Level.SEVERE, "The file " + configFile + " is broken. A backup file has failed to be created", e.getCause());
         } catch (final ConfigurateException e) {
             Essentials.getWrappedLogger().log(Level.SEVERE, e.getMessage(), e);
         } finally {
@@ -420,6 +446,10 @@ public class EssentialsConfiguration {
         }
     }
 
+    public boolean isTransaction() {
+        return transaction.get();
+    }
+
     public void setSaveHook(Runnable saveHook) {
         this.saveHook = saveHook;
     }

Essentials/src/main/java/com/earth2me/essentials/config/EssentialsUserConfiguration.java

@@ -52,7 +52,7 @@ public class EssentialsUserConfiguration extends EssentialsConfiguration {
 
     private File getAltFile() {
         final UUID fn = UUID.nameUUIDFromBytes(("OfflinePlayer:" + username.toLowerCase(Locale.ENGLISH)).getBytes(Charsets.UTF_8));
-        return new File(configFile.getParentFile(), fn.toString() + ".yml");
+        return new File(configFile.getParentFile(), fn + ".yml");
     }
 
     @Override

Essentials/src/main/java/com/earth2me/essentials/config/holders/UserConfigHolder.java

@@ -262,6 +262,16 @@ public class UserConfigHolder {
         this.lastAccountName = value;
     }
 
+    private @MonotonicNonNull String npcName;
+
+    public String npcName() {
+        return this.npcName;
+    }
+
+    public void npcName(final String value) {
+        this.npcName = value;
+    }
+
     private boolean powertoolsenabled = true;
 
     public boolean powerToolsEnabled() {
@@ -332,6 +342,20 @@ public class UserConfigHolder {
         this.shouting = value;
     }
 
+    @DeleteOnEmpty
+    private @MonotonicNonNull List<String> pastUsernames;
+
+    public List<String> pastUsernames() {
+        if (this.pastUsernames == null) {
+            this.pastUsernames = new ArrayList<>();
+        }
+        return this.pastUsernames;
+    }
+
+    public void pastUsernames(List<String> value) {
+        this.pastUsernames = value;
+    }
+
     private @NonNull Timestamps timestamps = new Timestamps();
 
     public Timestamps timestamps() {

Essentials/src/main/java/com/earth2me/essentials/config/serializers/MaterialTypeSerializer.java

@@ -17,7 +17,9 @@ public class MaterialTypeSerializer extends ScalarSerializer<Material> {
         if (obj instanceof String) {
             return Material.matchMaterial((String) obj);
         }
-        return null;
+
+        // Configurate will use an EnumSet to deserialize, which doesn't support null types. Default to air.
+        return Material.AIR;
     }
 
     @Override

Essentials/src/main/java/com/earth2me/essentials/craftbukkit/BanLookup.java

@@ -21,8 +21,9 @@ public final class BanLookup {
     }
 
     public static BanEntry getBanEntry(final IEssentials ess, final String name) {
-        final Set<BanEntry> benteries = ess.getServer().getBanList(BanList.Type.NAME).getBanEntries();
-        for (final BanEntry banEnt : benteries) {
+        final Set benteries = ess.getServer().getBanList(BanList.Type.NAME).getBanEntries();
+        for (final Object ob : benteries) {
+            final BanEntry banEnt = (BanEntry) ob;
             if (banEnt.getTarget().equals(name)) {
                 return banEnt;
             }

Essentials/src/main/java/com/earth2me/essentials/craftbukkit/Inventories.java

@@ -0,0 +1,405 @@
+package com.earth2me.essentials.craftbukkit;
+
+import com.earth2me.essentials.utils.MaterialUtil;
+import com.earth2me.essentials.utils.VersionUtil;
+import org.bukkit.entity.Player;
+import org.bukkit.inventory.EntityEquipment;
+import org.bukkit.inventory.Inventory;
+import org.bukkit.inventory.ItemStack;
+import org.bukkit.inventory.PlayerInventory;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.function.Predicate;
+
+public final class Inventories {
+    private static final int HELM_SLOT = 39;
+    private static final int CHEST_SLOT = 38;
+    private static final int LEG_SLOT = 37;
+    private static final int BOOT_SLOT = 36;
+    private static final boolean HAS_OFFHAND = VersionUtil.getServerBukkitVersion().isHigherThanOrEqualTo(VersionUtil.v1_9_R01);
+    private static final int INVENTORY_SIZE = HAS_OFFHAND ? 41 : 40;
+
+    private Inventories() {
+    }
+
+    public static ItemStack getItemInHand(final Player player) {
+        if (!HAS_OFFHAND) {
+            //noinspection deprecation
+            return player.getInventory().getItemInHand();
+        }
+        final PlayerInventory inventory = player.getInventory();
+        final ItemStack main = inventory.getItemInMainHand();
+        return !isEmpty(main) ? main : inventory.getItemInOffHand();
+    }
+
+    public static ItemStack getItemInMainHand(final Player player) {
+        if (!HAS_OFFHAND) {
+            //noinspection deprecation
+            return player.getInventory().getItemInHand();
+        }
+        return player.getInventory().getItemInMainHand();
+    }
+
+    public static void setItemInMainHand(final Player player, final ItemStack stack) {
+        if (HAS_OFFHAND) {
+            player.getInventory().setItemInMainHand(stack);
+        } else {
+            //noinspection deprecation
+            player.setItemInHand(stack);
+        }
+    }
+
+    public static void setItemInMainHand(final EntityEquipment entityEquipment, final ItemStack stack) {
+        if (HAS_OFFHAND) {
+            entityEquipment.setItemInMainHand(stack);
+        } else {
+            //noinspection deprecation
+            entityEquipment.setItemInHand(stack);
+        }
+    }
+
+    public static void setItemInMainHandDropChance(final EntityEquipment entityEquipment, final float chance) {
+        if (HAS_OFFHAND) {
+            entityEquipment.setItemInMainHandDropChance(chance);
+        } else {
+            //noinspection deprecation
+            entityEquipment.setItemInHandDropChance(chance);
+        }
+    }
+
+    public static boolean containsAtLeast(final Player player, final ItemStack item, int amount) {
+        for (final ItemStack invItem : player.getInventory().getContents()) {
+            if (isEmpty(invItem)) {
+                continue;
+            }
+            if (invItem.isSimilar(item)) {
+                amount -= invItem.getAmount();
+                if (amount <= 0) {
+                    return true;
+                }
+            }
+        }
+        return false;
+    }
+
+    public static boolean hasSpace(final Player player, final int maxStack, final boolean includeArmor, ItemStack... items) {
+        items = normalizeItems(cloneItems(items));
+        final InventoryData inventoryData = parseInventoryData(player.getInventory(), items, maxStack, includeArmor);
+
+        final List<Integer> emptySlots = inventoryData.getEmptySlots();
+        for (final ItemStack item : items) {
+            if (isEmpty(item)) {
+                continue;
+            }
+
+            final int itemMax = Math.max(maxStack, item.getMaxStackSize());
+            final List<Integer> partialSlots = inventoryData.getPartialSlots().get(item);
+            while (true) {
+                if (partialSlots == null || partialSlots.isEmpty()) {
+                    if (emptySlots.isEmpty()) {
+                        return false;
+                    }
+
+                    emptySlots.remove(0);
+                    if (item.getAmount() > itemMax) {
+                        item.setAmount(item.getAmount() - itemMax);
+                    } else {
+                        break;
+                    }
+                } else {
+                    final int slot = partialSlots.remove(0);
+                    ItemStack existing = player.getInventory().getItem(slot);
+                    if (isEmpty(existing)) {
+                        existing = item.clone();
+                        existing.setAmount(0);
+                    }
+
+                    final int amount = item.getAmount();
+                    final int existingAmount = existing.getAmount();
+
+                    if (amount + existingAmount <= itemMax) {
+                        break;
+                    } else {
+                        item.setAmount(amount + existingAmount - itemMax);
+                    }
+                }
+            }
+        }
+
+        return true;
+    }
+
+    public static Map<Integer, ItemStack> addItem(final Player player, final ItemStack... items) {
+        return addItem(player, 0, false, items);
+    }
+
+    public static Map<Integer, ItemStack> addItem(final Player player, final int maxStack, final ItemStack... items) {
+        return addItem(player, maxStack, false, items);
+    }
+
+    public static Map<Integer, ItemStack> addItem(final Player player, final int maxStack, final boolean allowArmor, ItemStack... items) {
+        items = normalizeItems(cloneItems(items));
+        final Map<Integer, ItemStack> leftover = new HashMap<>();
+        final InventoryData inventoryData = parseInventoryData(player.getInventory(), items, maxStack, allowArmor);
+
+        final List<Integer> emptySlots = inventoryData.getEmptySlots();
+        for (int i = 0; i < items.length; i++) {
+            final ItemStack item = items[i];
+            if (isEmpty(item)) {
+                continue;
+            }
+
+            final int itemMax = Math.max(maxStack, item.getMaxStackSize());
+            final List<Integer> partialSlots = inventoryData.getPartialSlots().get(item);
+            while (true) {
+                if (partialSlots == null || partialSlots.isEmpty()) {
+                    if (emptySlots.isEmpty()) {
+                        leftover.put(i, item);
+                        break;
+                    }
+
+                    final int slot = emptySlots.remove(0);
+                    if (item.getAmount() > itemMax) {
+                        final ItemStack split = item.clone();
+                        split.setAmount(itemMax);
+                        player.getInventory().setItem(slot, split);
+                        item.setAmount(item.getAmount() - itemMax);
+                    } else {
+                        player.getInventory().setItem(slot, item);
+                        break;
+                    }
+                } else {
+                    final int slot = partialSlots.remove(0);
+                    ItemStack existing = player.getInventory().getItem(slot);
+                    if (isEmpty(existing)) {
+                        existing = item.clone();
+                        existing.setAmount(0);
+                    }
+
+                    final int amount = item.getAmount();
+                    final int existingAmount = existing.getAmount();
+
+                    if (amount + existingAmount <= itemMax) {
+                        existing.setAmount(amount + existingAmount);
+                        player.getInventory().setItem(slot, existing);
+                        break;
+                    } else {
+                        existing.setAmount(itemMax);
+                        player.getInventory().setItem(slot, existing);
+                        item.setAmount(amount + existingAmount - itemMax);
+                    }
+                }
+            }
+        }
+
+        return leftover;
+    }
+
+    public static ItemStack[] getInventory(final Player player, final boolean includeArmor) {
+        final ItemStack[] items = new ItemStack[INVENTORY_SIZE];
+        for (int i = 0; i < items.length; i++) {
+            if (!includeArmor && isArmorSlot(i)) {
+                items[i] = null;
+                continue;
+            }
+
+            items[i] = player.getInventory().getItem(i);
+        }
+
+        return items;
+    }
+
+    public static void removeItemExact(final Player player, final ItemStack toRemove, final boolean includeArmor) {
+        removeItems(player, itemStack -> itemStack.equals(toRemove), includeArmor);
+    }
+
+    public static int removeItemSimilar(final Player player, final ItemStack toRemove, final boolean includeArmor) {
+        return removeItems(player, itemStack -> itemStack.isSimilar(toRemove), includeArmor);
+    }
+
+    public static int removeItems(final Player player, final Predicate<ItemStack> removePredicate, final boolean includeArmor) {
+        int removedAmount = 0;
+        final ItemStack[] items = player.getInventory().getContents();
+        for (int i = 0; i < items.length; i++) {
+            if (!includeArmor && isArmorSlot(i)) {
+                continue;
+            }
+
+            final ItemStack item = items[i];
+            if (isEmpty(item)) {
+                continue;
+            }
+
+            if (removePredicate.test(item)) {
+                removedAmount += item.getAmount();
+                item.setAmount(0);
+                player.getInventory().setItem(i, item);
+            }
+        }
+        return removedAmount;
+    }
+
+    public static boolean removeItemAmount(final Player player, final ItemStack toRemove, int amount) {
+        final List<Integer> clearSlots = new ArrayList<>();
+        final ItemStack[] items = player.getInventory().getContents();
+
+        for (int i = 0; i < items.length; i++) {
+            final ItemStack item = items[i];
+            if (isEmpty(item)) {
+                continue;
+            }
+
+            if (item.isSimilar(toRemove)) {
+                if (item.getAmount() >= amount) {
+                    item.setAmount(item.getAmount() - amount);
+                    player.getInventory().setItem(i, item);
+                    for (final int slot : clearSlots) {
+                        clearSlot(player, slot);
+                    }
+                    return true;
+                } else {
+                    amount -= item.getAmount();
+                    clearSlots.add(i);
+                }
+
+                if (amount == 0) {
+                    for (final int slot : clearSlots) {
+                        clearSlot(player, slot);
+                    }
+                    return true;
+                }
+            }
+        }
+        return false;
+    }
+
+    public static void clearSlot(final Player player, final int slot) {
+        final ItemStack item = player.getInventory().getItem(slot);
+        if (!isEmpty(item)) {
+            item.setAmount(0);
+            player.getInventory().setItem(slot, item);
+        }
+    }
+
+    public static void setSlot(final Player inventory, final int slot, final ItemStack item) {
+        inventory.getInventory().setItem(slot, item);
+    }
+
+    private static ItemStack[] normalizeItems(final ItemStack[] items) {
+        if (items.length <= 1) {
+            return items;
+        }
+
+        final ItemStack[] normalizedItems = new ItemStack[items.length];
+        int nextNormalizedIndex = 0;
+        inputLoop:
+        for (final ItemStack item : items) {
+            if (isEmpty(item)) {
+                continue;
+            }
+
+            for (int j = 0; j < nextNormalizedIndex; j++) {
+                final ItemStack normalizedItem = normalizedItems[j];
+                if (isEmpty(normalizedItem)) {
+                    continue;
+                }
+
+                if (item.isSimilar(normalizedItem)) {
+                    normalizedItem.setAmount(normalizedItem.getAmount() + item.getAmount());
+                    continue inputLoop;
+                }
+            }
+            normalizedItems[nextNormalizedIndex++] = item;
+        }
+
+        return normalizedItems;
+    }
+
+    private static ItemStack[] cloneItems(final ItemStack[] items) {
+        final ItemStack[] clonedItems = new ItemStack[items.length];
+        for (int i = 0; i < items.length; i++) {
+            final ItemStack item = items[i];
+            if (isEmpty(item)) {
+                continue;
+            }
+
+            clonedItems[i] = item.clone();
+        }
+
+        return clonedItems;
+    }
+
+    private static InventoryData parseInventoryData(final Inventory inventory, final ItemStack[] items, final int maxStack, final boolean includeArmor) {
+        final ItemStack[] inventoryContents = inventory.getContents();
+        final List<Integer> emptySlots = new ArrayList<>();
+        final HashMap<ItemStack, List<Integer>> partialSlots = new HashMap<>();
+
+        for (int i = 0; i < inventoryContents.length; i++) {
+            if (!includeArmor && isArmorSlot(i)) {
+                continue;
+            }
+
+            final ItemStack invItem = inventoryContents[i];
+            if (isEmpty(invItem)) {
+                emptySlots.add(i);
+            } else {
+                for (final ItemStack newItem : items) {
+                    if (invItem.getAmount() < Math.max(maxStack, invItem.getMaxStackSize()) && invItem.isSimilar(newItem)) {
+                        partialSlots.computeIfAbsent(newItem, k -> new ArrayList<>()).add(i);
+                    }
+                }
+            }
+        }
+
+        // Convert empty armor slots to partial slots if we have armor items in the inventory, otherwise remove them from the empty slots.
+        if (includeArmor) {
+            ItemStack helm = null;
+            ItemStack chest = null;
+            ItemStack legs = null;
+            ItemStack boots = null;
+            for (final ItemStack item : items) {
+                if (isEmpty(item)) {
+                    continue;
+                }
+                if (helm == null && MaterialUtil.isHelmet(item.getType())) {
+                    helm = item;
+                    if (emptySlots.contains(HELM_SLOT)) {
+                        partialSlots.computeIfAbsent(helm, k -> new ArrayList<>()).add(HELM_SLOT);
+                    }
+                } else if (chest == null && MaterialUtil.isChestplate(item.getType())) {
+                    chest = item;
+                    if (emptySlots.contains(CHEST_SLOT)) {
+                        partialSlots.computeIfAbsent(chest, k -> new ArrayList<>()).add(CHEST_SLOT);
+                    }
+                } else if (legs == null && MaterialUtil.isLeggings(item.getType())) {
+                    legs = item;
+                    if (emptySlots.contains(LEG_SLOT)) {
+                        partialSlots.computeIfAbsent(legs, k -> new ArrayList<>()).add(LEG_SLOT);
+                    }
+                } else if (boots == null && MaterialUtil.isBoots(item.getType())) {
+                    boots = item;
+                    if (emptySlots.contains(BOOT_SLOT)) {
+                        partialSlots.computeIfAbsent(boots, k -> new ArrayList<>()).add(BOOT_SLOT);
+                    }
+                }
+            }
+            emptySlots.remove((Object) HELM_SLOT);
+            emptySlots.remove((Object) CHEST_SLOT);
+            emptySlots.remove((Object) LEG_SLOT);
+            emptySlots.remove((Object) BOOT_SLOT);
+        }
+
+        return new InventoryData(emptySlots, partialSlots);
+    }
+
+    private static boolean isEmpty(final ItemStack stack) {
+        return stack == null || MaterialUtil.isAir(stack.getType());
+    }
+
+    private static boolean isArmorSlot(final int slot) {
+        return slot == HELM_SLOT || slot == CHEST_SLOT || slot == LEG_SLOT || slot == BOOT_SLOT;
+    }
+}

Essentials/src/main/java/com/earth2me/essentials/craftbukkit/InventoryData.java

@@ -0,0 +1,24 @@
+package com.earth2me.essentials.craftbukkit;
+
+import org.bukkit.inventory.ItemStack;
+
+import java.util.HashMap;
+import java.util.List;
+
+public class InventoryData {
+    private final List<Integer> emptySlots;
+    private final HashMap<ItemStack, List<Integer>> partialSlots;
+
+    public InventoryData(List<Integer> emptySlots, HashMap<ItemStack, List<Integer>> partialSlots) {
+        this.emptySlots = emptySlots;
+        this.partialSlots = partialSlots;
+    }
+
+    public List<Integer> getEmptySlots() {
+        return emptySlots;
+    }
+
+    public HashMap<ItemStack, List<Integer>> getPartialSlots() {
+        return partialSlots;
+    }
+}

Essentials/src/main/java/com/earth2me/essentials/craftbukkit/InventoryWorkaround.java

@@ -1,245 +0,0 @@
-package com.earth2me.essentials.craftbukkit;
-
-import com.earth2me.essentials.utils.VersionUtil;
-import org.bukkit.Bukkit;
-import org.bukkit.Material;
-import org.bukkit.entity.Player;
-import org.bukkit.inventory.EntityEquipment;
-import org.bukkit.inventory.Inventory;
-import org.bukkit.inventory.ItemStack;
-import org.bukkit.inventory.PlayerInventory;
-
-import java.util.Arrays;
-import java.util.HashMap;
-import java.util.Map;
-
-/*
- * This class can be removed when https://github.com/Bukkit/CraftBukkit/pull/193 is accepted to CraftBukkit
- */
-public final class InventoryWorkaround {
-    /*
-    Spigot 1.9, for whatever reason, decided to merge the armor and main player inventories without providing a way
-    to access the main inventory. There's lots of ugly code in here to work around that.
-     */
-    private static final int USABLE_PLAYER_INV_SIZE = 36;
-    private static final boolean IS_OFFHAND = VersionUtil.getServerBukkitVersion().isHigherThanOrEqualTo(VersionUtil.v1_9_R01);
-
-    private InventoryWorkaround() {
-    }
-
-    private static int firstPartial(final Inventory inventory, final ItemStack item, final int maxAmount) {
-        if (item == null) {
-            return -1;
-        }
-        final ItemStack[] stacks = inventory.getContents();
-        for (int i = 0; i < stacks.length; i++) {
-            final ItemStack cItem = stacks[i];
-            if (cItem != null && cItem.getAmount() < maxAmount && cItem.isSimilar(item)) {
-                return i;
-            }
-        }
-        return -1;
-    }
-
-    private static boolean isCombinedInventory(final Inventory inventory) {
-        return inventory instanceof PlayerInventory && inventory.getContents().length > USABLE_PLAYER_INV_SIZE;
-    }
-
-    // Clears inventory without clearing armor
-    public static void clearInventoryNoArmor(final PlayerInventory inventory) {
-        if (isCombinedInventory(inventory)) {
-            for (int i = 0; i < USABLE_PLAYER_INV_SIZE; i++) {
-                inventory.setItem(i, null);
-            }
-        } else {
-            inventory.clear();
-        }
-    }
-
-    private static Inventory makeTruncatedPlayerInventory(final PlayerInventory playerInventory) {
-        final Inventory fakeInventory = Bukkit.getServer().createInventory(null, USABLE_PLAYER_INV_SIZE);
-        fakeInventory.setContents(Arrays.copyOf(playerInventory.getContents(), fakeInventory.getSize()));
-        return fakeInventory;
-    }
-
-    // Returns what it couldn't store
-    // This will will abort if it couldn't store all items
-    public static Map<Integer, ItemStack> addAllItems(final Inventory inventory, final ItemStack... items) {
-        final ItemStack[] contents = inventory.getContents();
-
-        final Inventory fakeInventory;
-        if (isCombinedInventory(inventory)) {
-            fakeInventory = makeTruncatedPlayerInventory((PlayerInventory) inventory);
-        } else {
-            fakeInventory = Bukkit.getServer().createInventory(null, inventory.getType());
-            fakeInventory.setContents(contents);
-        }
-        final Map<Integer, ItemStack> overflow = addItems(fakeInventory, items);
-        if (overflow.isEmpty()) {
-            addItems(inventory, items);
-            return null;
-        }
-        return addItems(fakeInventory, items);
-    }
-
-    public static Map<Integer, ItemStack> addAllOversizedItems(final Inventory inventory, final int oversizedStacks, final ItemStack... items) {
-        final ItemStack[] contents = inventory.getContents();
-
-        final Inventory fakeInventory;
-        if (isCombinedInventory(inventory)) {
-            fakeInventory = makeTruncatedPlayerInventory((PlayerInventory) inventory);
-        } else {
-            fakeInventory = Bukkit.getServer().createInventory(null, inventory.getType());
-            fakeInventory.setContents(contents);
-        }
-        final Map<Integer, ItemStack> overflow = addOversizedItems(fakeInventory, oversizedStacks, items);
-        if (overflow.isEmpty()) {
-            addOversizedItems(inventory, oversizedStacks, items);
-            return null;
-        }
-        return overflow;
-    }
-
-    // Returns what it couldn't store
-    public static Map<Integer, ItemStack> addItems(final Inventory inventory, final ItemStack... items) {
-        return addOversizedItems(inventory, 0, items);
-    }
-
-    // Returns what it couldn't store
-    // Set oversizedStack to below normal stack size to disable oversized stacks
-    public static Map<Integer, ItemStack> addOversizedItems(final Inventory inventory, final int oversizedStacks, final ItemStack... items) {
-        if (isCombinedInventory(inventory)) {
-            final Inventory fakeInventory = makeTruncatedPlayerInventory((PlayerInventory) inventory);
-            final Map<Integer, ItemStack> overflow = addOversizedItems(fakeInventory, oversizedStacks, items);
-            for (int i = 0; i < fakeInventory.getContents().length; i++) {
-                inventory.setItem(i, fakeInventory.getContents()[i]);
-            }
-            return overflow;
-        }
-
-        final Map<Integer, ItemStack> leftover = new HashMap<>();
-
-        /*
-         * TODO: some optimization - Create a 'firstPartial' with a 'fromIndex' - Record the lastPartial per Material -
-         * Cache firstEmpty result
-         */
-
-        // combine items
-
-        final ItemStack[] combined = new ItemStack[items.length];
-        for (final ItemStack item : items) {
-            if (item == null || item.getAmount() < 1) {
-                continue;
-            }
-            for (int j = 0; j < combined.length; j++) {
-                if (combined[j] == null) {
-                    combined[j] = item.clone();
-                    break;
-                }
-                if (combined[j].isSimilar(item)) {
-                    combined[j].setAmount(combined[j].getAmount() + item.getAmount());
-                    break;
-                }
-            }
-        }
-
-        for (int i = 0; i < combined.length; i++) {
-            final ItemStack item = combined[i];
-            if (item == null || item.getType() == Material.AIR) {
-                continue;
-            }
-
-            while (true) {
-                // Do we already have a stack of it?
-                final int maxAmount = Math.max(oversizedStacks, item.getType().getMaxStackSize());
-                final int firstPartial = firstPartial(inventory, item, maxAmount);
-
-                // Drat! no partial stack
-                if (firstPartial == -1) {
-                    // Find a free spot!
-                    final int firstFree = inventory.firstEmpty();
-
-                    if (firstFree == -1) {
-                        // No space at all!
-                        leftover.put(i, item);
-                        break;
-                    } else {
-                        // More than a single stack!
-                        if (item.getAmount() > maxAmount) {
-                            final ItemStack stack = item.clone();
-                            stack.setAmount(maxAmount);
-                            inventory.setItem(firstFree, stack);
-                            item.setAmount(item.getAmount() - maxAmount);
-                        } else {
-                            // Just store it
-                            inventory.setItem(firstFree, item);
-                            break;
-                        }
-                    }
-                } else {
-                    // So, apparently it might only partially fit, well lets do just that
-                    final ItemStack partialItem = inventory.getItem(firstPartial);
-
-                    final int amount = item.getAmount();
-                    final int partialAmount = partialItem.getAmount();
-
-                    // Check if it fully fits
-                    if (amount + partialAmount <= maxAmount) {
-                        partialItem.setAmount(amount + partialAmount);
-                        break;
-                    }
-
-                    // It fits partially
-                    partialItem.setAmount(maxAmount);
-                    item.setAmount(amount + partialAmount - maxAmount);
-                }
-            }
-        }
-        return leftover;
-    }
-
-    @SuppressWarnings("deprecation")
-    public static void setItemInMainHand(final Player p, final ItemStack item) {
-        if (IS_OFFHAND) {
-            p.getInventory().setItemInMainHand(item);
-        } else {
-            p.setItemInHand(item);
-        }
-    }
-
-    @SuppressWarnings("deprecation")
-    public static void setItemInMainHand(final EntityEquipment invent, final ItemStack item) {
-        if (IS_OFFHAND) {
-            invent.setItemInMainHand(item);
-        } else {
-            invent.setItemInHand(item);
-        }
-    }
-
-    @SuppressWarnings("deprecation")
-    public static void setItemInMainHandDropChance(final EntityEquipment invent, final float chance) {
-        if (IS_OFFHAND) {
-            invent.setItemInMainHandDropChance(chance);
-        } else {
-            invent.setItemInHandDropChance(chance);
-        }
-    }
-
-    public static void setItemInOffHand(final Player p, final ItemStack item) {
-        if (IS_OFFHAND) {
-            p.getInventory().setItemInOffHand(item);
-        }
-    }
-
-    public static int clearItemInOffHand(final Player p, final ItemStack item) {
-        if (IS_OFFHAND) {
-            int removedAmount = 0;
-            if (p.getInventory().getItemInOffHand().getType().equals(item.getType())) {
-                removedAmount = p.getInventory().getItemInOffHand().getAmount();
-                p.getInventory().setItemInOffHand(null);
-            }
-            return removedAmount;
-        }
-        return 0;
-    }
-}

Essentials/src/main/java/com/earth2me/essentials/economy/vault/VaultEconomyProvider.java

@@ -1,6 +1,7 @@
 package com.earth2me.essentials.economy.vault;
 
 import com.earth2me.essentials.Essentials;
+import com.earth2me.essentials.OfflinePlayerStub;
 import com.earth2me.essentials.api.NoLoanPermittedException;
 import com.earth2me.essentials.api.UserDoesNotExistException;
 import com.earth2me.essentials.config.EssentialsUserConfiguration;
@@ -11,6 +12,7 @@ import net.ess3.api.MaxMoneyException;
 import net.milkbowl.vault.economy.Economy;
 import net.milkbowl.vault.economy.EconomyResponse;
 import org.bukkit.OfflinePlayer;
+import org.bukkit.entity.Player;
 
 import java.io.File;
 import java.math.BigDecimal;
@@ -308,21 +310,27 @@ public class VaultEconomyProvider implements Economy {
             npcConfig.setProperty("last-account-name", player.getName());
             npcConfig.setProperty("money", ess.getSettings().getStartingBalance());
             npcConfig.blockingSave();
-            ess.getUserMap().trackUUID(player.getUniqueId(), player.getName(), false);
+            // This will load the NPC into the UserMap + UUID cache
+            ess.getUsers().addCachedNpcName(player.getUniqueId(), player.getName());
+            ess.getUsers().getUser(player.getUniqueId());
             return true;
         }
 
         // Loading a v4 UUID that we somehow didn't track, mark it as a normal player and hope for the best, vault sucks :/
-        try {
-            if (ess.getSettings().isDebug()) {
-                ess.getLogger().info("Vault requested a player account creation for a v4 UUID: " + player);
-            }
-            ess.getUserMap().load(player);
-            return true;
-        } catch (UserDoesNotExistException e) {
-            e.printStackTrace();
-            return false;
+        if (ess.getSettings().isDebug()) {
+            ess.getLogger().info("Vault requested a player account creation for a v4 UUID: " + player);
         }
+
+        final Player userPlayer;
+        if (player instanceof Player) {
+            userPlayer = (Player) player;
+        } else {
+            final OfflinePlayerStub essPlayer = new OfflinePlayerStub(player.getUniqueId(), ess.getServer());
+            essPlayer.setName(player.getName());
+            userPlayer = essPlayer;
+        }
+        ess.getUsers().getUser(userPlayer);
+        return true;
     }
 
     @Override

Essentials/src/main/java/com/earth2me/essentials/items/AbstractItemDb.java

@@ -2,6 +2,7 @@ package com.earth2me.essentials.items;
 
 import com.earth2me.essentials.IConf;
 import com.earth2me.essentials.User;
+import com.earth2me.essentials.craftbukkit.Inventories;
 import com.earth2me.essentials.utils.FormatUtil;
 import com.earth2me.essentials.utils.MaterialUtil;
 import com.earth2me.essentials.utils.VersionUtil;
@@ -156,14 +157,14 @@ public abstract class AbstractItemDb implements IConf, net.ess3.api.IItemDb {
         } else if (args[0].equalsIgnoreCase("hand")) {
             is.add(user.getItemInHand().clone());
         } else if (args[0].equalsIgnoreCase("inventory") || args[0].equalsIgnoreCase("invent") || args[0].equalsIgnoreCase("all")) {
-            for (final ItemStack stack : user.getBase().getInventory().getContents()) {
+            for (final ItemStack stack : Inventories.getInventory(user.getBase(), true)) {
                 if (stack == null || stack.getType() == Material.AIR) {
                     continue;
                 }
                 is.add(stack.clone());
             }
         } else if (args[0].equalsIgnoreCase("blocks")) {
-            for (final ItemStack stack : user.getBase().getInventory().getContents()) {
+            for (final ItemStack stack : Inventories.getInventory(user.getBase(), true)) {
                 if (stack == null || stack.getType() == Material.AIR || !stack.getType().isBlock()) {
                     continue;
                 }

Essentials/src/main/java/com/earth2me/essentials/perm/IPermissionsHandler.java

@@ -3,6 +3,7 @@ package com.earth2me.essentials.perm;
 import com.earth2me.essentials.Essentials;
 import com.earth2me.essentials.User;
 import com.earth2me.essentials.utils.TriState;
+import org.bukkit.OfflinePlayer;
 import org.bukkit.entity.Player;
 
 import java.util.List;
@@ -10,9 +11,15 @@ import java.util.function.Function;
 import java.util.function.Supplier;
 
 public interface IPermissionsHandler {
-    String getGroup(Player base);
+    boolean addToGroup(OfflinePlayer base, String group);
 
-    List<String> getGroups(Player base);
+    boolean removeFromGroup(OfflinePlayer base, String group);
+
+    String getGroup(OfflinePlayer base);
+
+    List<String> getGroups(OfflinePlayer base);
+
+    List<String> getGroups();
 
     boolean canBuild(Player base, String group);
 

Essentials/src/main/java/com/earth2me/essentials/perm/PermissionsHandler.java

@@ -10,8 +10,10 @@ import com.earth2me.essentials.perm.impl.ModernVaultHandler;
 import com.earth2me.essentials.perm.impl.SuperpermsHandler;
 import com.earth2me.essentials.utils.TriState;
 import com.google.common.collect.ImmutableSet;
+import org.bukkit.OfflinePlayer;
 import org.bukkit.entity.Player;
 
+import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
@@ -34,7 +36,7 @@ public class PermissionsHandler implements IPermissionsHandler {
     }
 
     @Override
-    public String getGroup(final Player base) {
+    public String getGroup(final OfflinePlayer base) {
         final long start = System.nanoTime();
         String group = handler.getGroup(base);
         if (group == null) {
@@ -45,16 +47,42 @@ public class PermissionsHandler implements IPermissionsHandler {
     }
 
     @Override
-    public List<String> getGroups(final Player base) {
+    public List<String> getGroups(final OfflinePlayer base) {
         final long start = System.nanoTime();
-        List<String> groups = handler.getGroups(base);
+        final List<String> groups = new ArrayList<>();
+        groups.add(defaultGroup);
+        groups.addAll(handler.getGroups(base));
+        checkPermLag(start, String.format("Getting groups for %s", base.getName()));
+        return Collections.unmodifiableList(groups);
+    }
+
+    @Override
+    public List<String> getGroups() {
+        final long start = System.nanoTime();
+        List<String> groups = handler.getGroups();
         if (groups == null || groups.isEmpty()) {
             groups = Collections.singletonList(defaultGroup);
         }
-        checkPermLag(start, String.format("Getting groups for %s", base.getName()));
+        checkPermLag(start, "Getting all groups");
         return Collections.unmodifiableList(groups);
     }
 
+    @Override
+    public boolean addToGroup(OfflinePlayer base, String group) {
+        final long start = System.nanoTime();
+        final boolean result = handler.addToGroup(base, group);
+        checkPermLag(start, String.format("Adding group to %s", base.getName()));
+        return result;
+    }
+
+    @Override
+    public boolean removeFromGroup(OfflinePlayer base, String group) {
+        final long start = System.nanoTime();
+        final boolean result = handler.removeFromGroup(base, group);
+        checkPermLag(start, String.format("Removing group from %s", base.getName()));
+        return result;
+    }
+
     @Override
     public boolean canBuild(final Player base, final String group) {
         return handler.canBuild(base, group);

Essentials/src/main/java/com/earth2me/essentials/perm/impl/AbstractVaultHandler.java

@@ -3,6 +3,7 @@ package com.earth2me.essentials.perm.impl;
 import net.milkbowl.vault.chat.Chat;
 import net.milkbowl.vault.permission.Permission;
 import org.bukkit.Bukkit;
+import org.bukkit.OfflinePlayer;
 import org.bukkit.entity.Player;
 import org.bukkit.plugin.RegisteredServiceProvider;
 import org.bukkit.plugin.java.JavaPlugin;
@@ -32,13 +33,34 @@ public abstract class AbstractVaultHandler extends SuperpermsHandler {
     }
 
     @Override
-    public String getGroup(final Player base) {
-        return perms.getPrimaryGroup(base);
+    public String getGroup(final OfflinePlayer base) {
+        if (base.isOnline()) {
+            return perms.getPrimaryGroup(base.getPlayer());
+        }
+        return perms.getPrimaryGroup(null, base);
     }
 
     @Override
-    public List<String> getGroups(final Player base) {
-        return Arrays.asList(perms.getPlayerGroups(base));
+    public List<String> getGroups(final OfflinePlayer base) {
+        if (base.isOnline()) {
+            return Arrays.asList(perms.getPlayerGroups(base.getPlayer()));
+        }
+        return Arrays.asList(perms.getPlayerGroups(null, base));
+    }
+
+    @Override
+    public List<String> getGroups() {
+        return Arrays.asList(perms.getGroups());
+    }
+
+    @Override
+    public boolean addToGroup(OfflinePlayer base, String group) {
+        return perms.playerAddGroup(null, base, group);
+    }
+
+    @Override
+    public boolean removeFromGroup(OfflinePlayer base, String group) {
+        return perms.playerRemoveGroup(null, base, group);
     }
 
     @Override

Essentials/src/main/java/com/earth2me/essentials/perm/impl/LuckPermsHandler.java

@@ -70,11 +70,19 @@ public class LuckPermsHandler extends ModernVaultHandler {
             // If the player doesn't exist in the UserMap, just skip
             // Ess will cause performance problems for permissions checks if it attempts to
             // perform i/o to load the user data otherwise.
-            if (!ess.getUserMap().userExists(target.getUniqueId())) {
+            if (!ess.getUsers().getAllUserUUIDs().contains(target.getUniqueId())) {
+                return;
+            }
+
+            final User user = ess.getUsers().loadUncachedUser(target.getUniqueId());
+
+            // This will occur for first time players during join,
+            // None of our contexts would apply to that kind of person anyway,
+            // lets just skip :O
+            if (user == null) {
                 return;
             }
 
-            final User user = ess.getUser(target);
             for (Calculator calculator : this.calculators) {
                 calculator.function.apply(user).forEach(value -> consumer.accept(calculator.id, value));
             }

Essentials/src/main/java/com/earth2me/essentials/perm/impl/SuperpermsHandler.java

@@ -5,6 +5,7 @@ import com.earth2me.essentials.User;
 import com.earth2me.essentials.perm.IPermissionsHandler;
 import com.earth2me.essentials.utils.TriState;
 import org.bukkit.Bukkit;
+import org.bukkit.OfflinePlayer;
 import org.bukkit.entity.Player;
 import org.bukkit.permissions.Permission;
 import org.bukkit.permissions.PermissionAttachmentInfo;
@@ -21,12 +22,27 @@ public class SuperpermsHandler implements IPermissionsHandler {
     }
 
     @Override
-    public String getGroup(final Player base) {
+    public boolean addToGroup(OfflinePlayer base, String group) {
+        return false;
+    }
+
+    @Override
+    public boolean removeFromGroup(OfflinePlayer base, String group) {
+        return false;
+    }
+
+    @Override
+    public String getGroup(final OfflinePlayer base) {
         return null;
     }
 
     @Override
-    public List<String> getGroups(final Player base) {
+    public List<String> getGroups(final OfflinePlayer base) {
+        return null;
+    }
+
+    @Override
+    public List<String> getGroups() {
         return null;
     }