Release 2.16.1

Bump org.apache.maven.plugins:maven-compiler-plugin from 3.15.0 to 3.16.0

README.md

@@ -1,13 +1,14 @@
 # Item-NBT-API
 
+[![Modrinth](https://img.shields.io/modrinth/dt/nbtapi?logo=modrinth&label=Modrinth%20downloads)](https://modrinth.com/plugin/nbtapi)
+[![Discord](https://img.shields.io/discord/342814924310970398?color=%237289DA&label=Discord&logo=discord&logoColor=white)](https://discordapp.com/invite/yk4caxM)
+
 Add custom NBT tags to Items/Tiles/Entities without NMS! Modify NBT and store it in Files, other NBT, or as String in yaml/json/SQL/Redis.
 [Server Owner/Developer Wiki](https://github.com/tr7zw/Item-NBT-API/wiki)
 
 ### Build/Maven/Sonar Status
 
 [![Build Status](https://ci.codemc.org/buildStatus/icon?job=Tr7zw%2FItem-NBT-API)](https://ci.codemc.org/job/Tr7zw/job/Item-NBT-API/)[![](https://sonarcloud.io/api/project_badges/measure?project=tr7zw_Item-NBT-API&metric=ncloc)](https://sonarcloud.io/summary/overall?id=tr7zw_Item-NBT-API)[![](https://sonarcloud.io/api/project_badges/measure?project=tr7zw_Item-NBT-API&metric=duplicated_lines_density)](https://sonarcloud.io/summary/overall?id=tr7zw_Item-NBT-API)[![](https://sonarcloud.io/api/project_badges/measure?project=tr7zw_Item-NBT-API&metric=sqale_rating)](https://sonarcloud.io/summary/overall?id=tr7zw_Item-NBT-API)
-[![Discord](https://img.shields.io/discord/342814924310970398?color=%237289DA&label=Discord&logo=discord&logoColor=white)](https://discordapp.com/invite/yk4caxM)
-[![Patreon](https://img.shields.io/endpoint.svg?url=https%3A%2F%2Fshieldsio-patreon.vercel.app%2Fapi%3Fusername%3Dtr7zw%26type%3Dpatrons&style=for-the-badge)](https://www.patreon.com/tr7zw)
 
 ### SpigotMC Status
 

item-nbt-api/pom.xml

@@ -5,7 +5,7 @@
   <parent>
     <groupId>de.tr7zw</groupId>
     <artifactId>item-nbt-parent</artifactId>
-    <version>2.14.0</version>
+    <version>2.16.1</version>
   </parent>
 
   <artifactId>item-nbt-api</artifactId>
@@ -18,6 +18,12 @@
 	    <version>4.0.26</version>
 	    <scope>provided</scope>
 	</dependency>
+	<dependency>
+	  <groupId>org.bstats</groupId>
+	  <artifactId>bstats-bukkit</artifactId>
+	  <version>3.2.1</version>
+	  <scope>compile</scope>
+	</dependency>
   </dependencies>
 
   <build>
@@ -32,9 +38,15 @@
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-shade-plugin</artifactId>
-        <version>3.6.0</version>
+        <version>3.6.2</version>
         <configuration>
-          <createDependencyReducedPom>false</createDependencyReducedPom>
+	        <relocations>
+	          <relocation>
+	            <pattern>org.bstats</pattern>
+	            <shadedPattern>de.tr7zw.changeme.nbtapi.utils.metrics</shadedPattern>
+	          </relocation>
+	        </relocations>
+          <createDependencyReducedPom>true</createDependencyReducedPom>
           <transformers>
             <transformer implementation="org.apache.maven.plugins.shade.resource.AppendingTransformer">
               <resource>LICENSE</resource>

item-nbt-api/src/main/java/de/tr7zw/changeme/nbtapi/NBT.java

@@ -9,6 +9,9 @@ import java.util.logging.Level;
 
 import javax.annotation.Nullable;
 
+import de.tr7zw.changeme.nbtapi.utils.CheckUtil;
+import org.bukkit.Chunk;
+import org.bukkit.block.Block;
 import org.bukkit.block.BlockState;
 import org.bukkit.entity.Entity;
 import org.bukkit.inventory.ItemStack;
@@ -727,4 +730,204 @@ public class NBT {
         return val;
     }
 
+    /**
+     * Reads block‑specific data that was previously stored in the chunk's
+     * persistent data container.
+     * <p>
+     * The data is stored inside the {@code blocks} compound of the chunk's
+     * persistent data container, using a key formed as {@code X_Y_Z} where
+     * X, Y, Z are the block's coordinates.
+     * <p>
+     * <b>Minecraft version:</b> this method requires <b>1.16.4 or newer</b>.
+     *
+     * @param block    the block whose stored data is to be read
+     * @param consumer the consumer that receives a {@link ReadableNBT} view of the data
+     */
+    public static void readChunkPDC(Block block, Consumer<ReadableNBT> consumer) {
+        processBlockChunkPDC(block, false, nbt -> {
+            consumer.accept(nbt);
+            return null;
+        });
+    }
+
+    /**
+     * Reads block‑specific data from the chunk's persistent data container and
+     * applies a function to produce a result.
+     * <p>
+     * The data is stored inside the {@code blocks} compound of the chunk's
+     * persistent data container, using a key formed as {@code X_Y_Z} where
+     * X, Y, Z are the block's coordinates.
+     * <p>
+     * <b>Minecraft version:</b> this method requires <b>1.16.4 or newer</b>.
+     *
+     * @param block    the block whose stored data is to be read
+     * @param function the function that processes the {@link ReadableNBT} and
+     *                 returns a value
+     * @param <T>      the type of the returned value
+     * @return the result of the function applied to the data
+     */
+    public static <T> T readAndGetChunkPDC(Block block, Function<ReadableNBT, T> function) {
+        return processBlockChunkPDC(block, false, function::apply);
+    }
+
+    /**
+     * Modifies block‑specific data stored in the chunk's persistent data container.
+     * <p>
+     * The data is stored inside the {@code blocks} compound of the chunk's
+     * persistent data container, using a key formed as {@code X_Y_Z} where
+     * X, Y, Z are the block's coordinates.
+     * <p>
+     * <b>Caution:</b> the data remains even if the block is broken, replaced, moved,
+     * or exploded, etc. You should manually remove the data when it is no longer needed.
+     * <p>
+     * <b>Minecraft version:</b> this method requires <b>1.16.4 or newer</b>.
+     *
+     * @param block    the block whose data is to be modified
+     * @param consumer the consumer that receives the {@link ReadWriteNBT} and
+     *                 applies modifications
+     */
+    public static void modifyChunkPDC(Block block, Consumer<ReadWriteNBT> consumer) {
+        processBlockChunkPDC(block, true, nbt -> {
+            consumer.accept(nbt);
+            return null;
+        });
+    }
+
+    /**
+     * Modifies block‑specific data in the chunk's persistent data container and
+     * returns a result computed from the modified data.
+     * <p>
+     * The data is stored inside the {@code blocks} compound of the chunk's
+     * persistent data container, using a key formed as {@code X_Y_Z} where
+     * X, Y, Z are the block's coordinates.
+     * <p>
+     * <b>Caution:</b> the data remains even if the block is broken, replaced, moved,
+     * or exploded, etc. You should manually remove the data when it is no longer needed.
+     * <p>
+     * <b>Minecraft version:</b> this method requires <b>1.16.4 or newer</b>.
+     *
+     * @param block    the block whose data is to be modified
+     * @param function the function that receives the {@link ReadWriteNBT}, modifies
+     *                 it, and returns a value
+     * @param <T>      the type of the returned value
+     * @return the result of the function after modification
+     */
+    public static <T> T modifyAndGetChunkPDC(Block block, Function<ReadWriteNBT, T> function) {
+        return processBlockChunkPDC(block, true, function::apply);
+    }
+
+    private static <T> T processBlockChunkPDC(Block block, boolean createIfAbsent, Function<NBTCompound, T> action) {
+        CheckUtil.assertAvailable(MinecraftVersion.MC1_16_R3);
+
+        String blockKey = block.getX() + "_" + block.getY() + "_" + block.getZ();
+
+        NBTCompound chunkData = new NBTPersistentDataContainer(block.getChunk().getPersistentDataContainer(), !createIfAbsent);
+
+        NBTCompound blocksData = createIfAbsent
+            ? chunkData.getOrCreateCompound("blocks")
+            : chunkData.getCompound("blocks");
+
+        NBTCompound blockData;
+        if (createIfAbsent) {
+            blockData = blocksData.getOrCreateCompound(blockKey);
+        } else {
+            blockData = blocksData == null ? null : blocksData.getCompound(blockKey);
+            if (blockData == null) {
+                blockData = new NBTContainer().setReadOnly(true);
+            }
+        }
+
+        T result = action.apply(blockData);
+
+        if (createIfAbsent) {
+            if (blockData.isEmpty()) {
+                blocksData.removeKey(blockKey);
+            }
+            if (blocksData.isEmpty()) {
+                chunkData.removeKey("blocks");
+            }
+        }
+
+        if (result instanceof ReadableNBT || result instanceof ReadableNBTList<?>) {
+            throw new NbtApiException("Tried returning part of the NBT to outside of the NBT scope!");
+        }
+
+        return result;
+    }
+
+    /**
+     * Reads the chunk's persistent data container.
+     * <p>
+     * <b>Minecraft version:</b> this method requires <b>1.16.4 or newer</b>.
+     *
+     * @param chunk    the chunk whose persistent data is to be read
+     * @param consumer the consumer that receives a {@link ReadableNBT} view of the data
+     */
+    public static void readChunkPDC(Chunk chunk, Consumer<ReadableNBT> consumer) {
+        processChunkPDC(chunk, false, nbt -> {
+            consumer.accept(nbt);
+            return null;
+        });
+    }
+
+    /**
+     * Reads the chunk's persistent data container and applies a function to produce a result.
+     * <p>
+     * <b>Minecraft version:</b> this method requires <b>1.16.4 or newer</b>.
+     *
+     * @param chunk    the chunk whose persistent data is to be read
+     * @param function the function that processes the {@link ReadableNBT} and
+     *                 returns a value
+     * @param <T>      the type of the returned value
+     * @return the result of the function applied to the data
+     */
+    public static <T> T readAndGetChunkPDC(Chunk chunk, Function<ReadableNBT, T> function) {
+        return processChunkPDC(chunk, false, function::apply);
+    }
+
+    /**
+     * Modifies the chunk's persistent data container.
+     * <p>
+     * <b>Minecraft version:</b> this method requires <b>1.16.4 or newer</b>.
+     *
+     * @param chunk    the chunk whose persistent data is to be modified
+     * @param consumer the consumer that receives the {@link ReadWriteNBT} and
+     *                 applies modifications
+     */
+    public static void modifyChunkPDC(Chunk chunk, Consumer<ReadWriteNBT> consumer) {
+        processChunkPDC(chunk, true, nbt -> {
+            consumer.accept(nbt);
+            return null;
+        });
+    }
+
+    /**
+     * Modifies the chunk's persistent data container and returns a result computed from the modified data.
+     * <p>
+     * <b>Minecraft version:</b> this method requires <b>1.16.4 or newer</b>.
+     *
+     * @param chunk    the chunk whose persistent data is to be modified
+     * @param function the function that receives the {@link ReadWriteNBT}, modifies
+     *                 it, and returns a value
+     * @param <T>      the type of the returned value
+     * @return the result of the function after modification
+     */
+    public static <T> T modifyAndGetChunkPDC(Chunk chunk, Function<ReadWriteNBT, T> function) {
+        return processChunkPDC(chunk, true, function::apply);
+    }
+
+    private static <T> T processChunkPDC(Chunk chunk, boolean createIfAbsent, Function<NBTCompound, T> action) {
+        CheckUtil.assertAvailable(MinecraftVersion.MC1_16_R3);
+
+        NBTCompound chunkData = new NBTPersistentDataContainer(chunk.getPersistentDataContainer(), !createIfAbsent);
+
+        T result = action.apply(chunkData);
+
+        if (result instanceof ReadableNBT || result instanceof ReadableNBTList<?>) {
+            throw new NbtApiException("Tried returning part of the NBT to outside of the NBT scope!");
+        }
+
+        return result;
+    }
+
 }

item-nbt-api/src/main/java/de/tr7zw/changeme/nbtapi/NBTBlock.java

@@ -7,16 +7,17 @@ import de.tr7zw.changeme.nbtapi.utils.MinecraftVersion;
 /**
  * Helper class to store NBT data to Block Locations. Use getData() to get the
  * NBT instance. Important notes:
- * 
+ * <p>
  * - Non BlockEntities can not have NBT data. This stores the data to the chunk
  * instead!
- * 
+ * <p>
  * - The data is really just on the location. If the block gets
  * broken/changed/exploded/moved etc., the data is still on that location!
  * 
  * @author tr7zw
- *
+ * @deprecated use methods in {@link NBT} class to read/modify block's NBT
  */
+@Deprecated
 public class NBTBlock {
 
     private final Block block;
@@ -30,6 +31,13 @@ public class NBTBlock {
         nbtChunk = new NBTChunk(block.getChunk());
     }
 
+    /**
+     * Gets the block NBT data stored within the chunk's PDC.
+     *
+     * @return block NBT data
+     * @deprecated use methods in {@link NBT} class to read/modify block's NBT
+     */
+    @Deprecated
     public NBTCompound getData() {
         return nbtChunk.getPersistentDataContainer().getOrCreateCompound("blocks")
                 .getOrCreateCompound(block.getX() + "_" + block.getY() + "_" + block.getZ());

item-nbt-api/src/main/java/de/tr7zw/changeme/nbtapi/NBTChunk.java

@@ -5,6 +5,12 @@ import org.bukkit.Chunk;
 import de.tr7zw.changeme.nbtapi.utils.CheckUtil;
 import de.tr7zw.changeme.nbtapi.utils.MinecraftVersion;
 
+/**
+ * Helper class to store NBT data to {@link Chunk}'s PDC (persistent data container).
+ *
+ * @deprecated use methods in {@link NBT} class to read/modify chunk's nbt
+ */
+@Deprecated
 public class NBTChunk {
 
     private final Chunk chunk;

item-nbt-api/src/main/java/de/tr7zw/changeme/nbtapi/NBTCompound.java

@@ -5,6 +5,7 @@ import java.io.Serializable;
 import java.util.Arrays;
 import java.util.HashSet;
 import java.util.List;
+import java.util.Optional;
 import java.util.Set;
 import java.util.UUID;
 import java.util.concurrent.locks.Lock;
@@ -19,6 +20,7 @@ import de.tr7zw.changeme.nbtapi.iface.ReadableNBT;
 import de.tr7zw.changeme.nbtapi.utils.CheckUtil;
 import de.tr7zw.changeme.nbtapi.utils.MinecraftVersion;
 import de.tr7zw.changeme.nbtapi.utils.PathUtil;
+import de.tr7zw.changeme.nbtapi.utils.UUIDUtil;
 import de.tr7zw.changeme.nbtapi.utils.PathUtil.PathSegment;
 import de.tr7zw.changeme.nbtapi.utils.nmsmappings.Forge1710Mappings;
 import de.tr7zw.changeme.nbtapi.utils.nmsmappings.ReflectionMethod;
@@ -98,10 +100,13 @@ public class NBTCompound implements ReadWriteNBT {
             return readOnlyCache;
         }
         Object rootnbttag = getCompound();
+        if (rootnbttag instanceof Optional<?>) {
+            rootnbttag = ((Optional<Object>) rootnbttag).orElse(null);
+        }
         if (rootnbttag == null) {
             return null;
         }
-        if (!NBTReflectionUtil.valideCompound(this))
+        if (!NBTReflectionUtil.validCompound(this))
             throw new NbtApiException("The Compound wasn't able to be linked back to the root!");
         Object workingtag = NBTReflectionUtil.getToCompount(rootnbttag, this);
         if (readOnly) {
@@ -657,7 +662,9 @@ public class NBTCompound implements ReadWriteNBT {
     public void setUUID(String key, UUID value) {
         try {
             writeLock.lock();
-            if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_16_R1)) {
+            if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_21_R4)) {
+                setIntArray(key, UUIDUtil.uuidToIntArray(value));
+            } else if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_16_R1)) {
                 NBTReflectionUtil.setData(this, ReflectionMethod.COMPOUND_SET_UUID, key, value);
             } else {
                 setString(key, value.toString());
@@ -678,10 +685,13 @@ public class NBTCompound implements ReadWriteNBT {
     public UUID getUUID(String key) {
         try {
             readLock.lock();
-            if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_16_R1)
-                    && getType(key) == NBTType.NBTTagIntArray) {
+            NBTType type = getType(key);
+            if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_21_R4) && type == NBTType.NBTTagIntArray) {
+                return UUIDUtil.uuidFromIntArray(getIntArray(key));
+            } else if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_16_R1)
+                    && type == NBTType.NBTTagIntArray) {
                 return (UUID) NBTReflectionUtil.getData(this, ReflectionMethod.COMPOUND_GET_UUID, key);
-            } else if (getType(key) == NBTType.NBTTagString) {
+            } else if (type == NBTType.NBTTagString) {
                 try {
                     return UUID.fromString(getString(key));
                 } catch (IllegalArgumentException ex) {
@@ -786,7 +796,7 @@ public class NBTCompound implements ReadWriteNBT {
             if (getType(name) != NBTType.NBTTagCompound)
                 return null;
             NBTCompound next = new NBTCompound(this, name, readOnly);
-            if (NBTReflectionUtil.valideCompound(next))
+            if (NBTReflectionUtil.validCompound(next))
                 return next;
             return null;
         } finally {
@@ -1343,7 +1353,13 @@ public class NBTCompound implements ReadWriteNBT {
                 Object nbtbase = NBTReflectionUtil.getData(this, ReflectionMethod.COMPOUND_GET, name);
                 if (nbtbase == null)
                     return null;
-                return NBTType.valueOf((byte) ReflectionMethod.COMPOUND_OWN_TYPE.run(nbtbase));
+                return NBTType.valueOf((byte) ReflectionMethod.COMPOUND_OWN_TYPE_LEGACY.run(nbtbase));
+            }
+            if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_21_R4)) {
+                Object o = NBTReflectionUtil.getData(this, ReflectionMethod.COMPOUND_GET, name);
+                if (o == null)
+                    return null;
+                return NBTType.fromName((String)ReflectionMethod.TAGTYPE_GET_NAME.run(ReflectionMethod.TAGTYPE_OWN_TYPE.run(o)));
             }
             Object o = NBTReflectionUtil.getData(this, ReflectionMethod.COMPOUND_GET_TYPE, name);
             if (o == null)
@@ -1460,6 +1476,106 @@ public class NBTCompound implements ReadWriteNBT {
         return false;
     }
 
+    @Override
+    public NBTCompound extractDifference(ReadableNBT other) {
+        if (this == other)
+            return new NBTContainer();
+
+        if (other instanceof NBTCompound) {
+            return saveDiff(new NBTContainer(), this, (NBTCompound) other);
+        } else {
+            throw new NbtApiException("Unknown NBT object: " + other);
+        }
+    }
+
+    private static NBTCompound saveDiff(NBTCompound saveTo, NBTCompound compA, NBTCompound compB) {
+        for (String key : compA.getKeys()) {
+            saveDiff(saveTo, compA, compB, key);
+        }
+        return saveTo;
+    }
+
+    private static void saveDiff(NBTCompound saveTo, NBTCompound compA, NBTCompound compB, String key) {
+        boolean typeMismatch = compA.getType(key) != compB.getType(key);
+        switch (compA.getType(key)) {
+            case NBTTagByte:
+                if (typeMismatch || !isEqual(compA, compB, key)) {
+                    saveTo.setByte(key, compA.getByte(key));
+                }
+                return;
+            case NBTTagByteArray:
+                if (typeMismatch || !isEqual(compA, compB, key)) {
+                    saveTo.setByteArray(key, compA.getByteArray(key));
+                }
+                return;
+            case NBTTagCompound: {
+                NBTCompound tmp1 = compA.getCompound(key);
+                if (tmp1 == null) return;
+                if (typeMismatch) {
+                    saveTo.addCompound(key).mergeCompound(tmp1);
+                } else {
+                    NBTCompound tmp2 = compB.getCompound(key);
+                    if (tmp2 == null) {
+                        saveTo.addCompound(key).mergeCompound(tmp1);
+                        return;
+                    }
+                    NBTCompound tmpDiff = tmp1.extractDifference(tmp2);
+                    if (!tmpDiff.getKeys().isEmpty()) {
+                        saveTo.addCompound(key).mergeCompound(tmpDiff);
+                    }
+                }
+                return;
+            }
+            case NBTTagDouble:
+                if (typeMismatch || !isEqual(compA, compB, key)) {
+                    saveTo.setDouble(key, compA.getDouble(key));
+                }
+                return;
+            case NBTTagEnd:
+                return; // ??
+            case NBTTagFloat:
+                if (typeMismatch || !isEqual(compA, compB, key)) {
+                    saveTo.setFloat(key, compA.getFloat(key));
+                }
+                return;
+            case NBTTagInt:
+                if (typeMismatch || !isEqual(compA, compB, key)) {
+                    saveTo.setInteger(key, compA.getInteger(key));
+                }
+                return;
+            case NBTTagIntArray:
+                if (typeMismatch || !isEqual(compA, compB, key)) {
+                    saveTo.setIntArray(key, compA.getIntArray(key));
+                }
+                return;
+            case NBTTagList:
+                if (typeMismatch || !isEqual(compA, compB, key)) {
+                    saveTo.set(key, NBTReflectionUtil.getEntry(compA, key));
+                }
+                return;
+            case NBTTagLong:
+                if (typeMismatch || !isEqual(compA, compB, key)) {
+                    saveTo.setLong(key, compA.getLong(key));
+                }
+                return;
+            case NBTTagShort:
+                if (typeMismatch || !isEqual(compA, compB, key)) {
+                    saveTo.setShort(key, compA.getShort(key));
+                }
+                return;
+            case NBTTagString:
+                if (typeMismatch || !isEqual(compA, compB, key)) {
+                    saveTo.setString(key, compA.getString(key));
+                }
+                return;
+            case NBTTagLongArray:
+                if (typeMismatch || !isEqual(compA, compB, key)) {
+                    saveTo.setLongArray(key, compA.getLongArray(key));
+                }
+                return;
+        }
+    }
+
     private static boolean isEqual(NBTCompound compA, NBTCompound compB, String key) {
         if (compA.getType(key) != compB.getType(key))
             return false;

item-nbt-api/src/main/java/de/tr7zw/changeme/nbtapi/NBTContainer.java

@@ -21,6 +21,8 @@ public class NBTContainer extends NBTCompound {
 
     /**
      * Creates an empty, standalone NBTCompound
+     *
+     * @deprecated use {@link NBT#createNBTObject()}
      */
     @Deprecated
     public NBTContainer() {

item-nbt-api/src/main/java/de/tr7zw/changeme/nbtapi/NBTList.java

@@ -304,8 +304,8 @@ public abstract class NBTList<T> implements List<T>, ReadWriteNBTList<T> {
         try {
             parent.getWriteLock().lock();
             int size = size();
-            int id = -1;
-            while ((id = indexOf(o)) != -1) {
+            int id = indexOf(o);
+            if (id != -1) {
                 remove(id);
             }
             return size != size();

item-nbt-api/src/main/java/de/tr7zw/changeme/nbtapi/NBTPersistentDataContainer.java

@@ -11,7 +11,11 @@ public class NBTPersistentDataContainer extends NBTCompound {
     private final PersistentDataContainer container;
 
     public NBTPersistentDataContainer(PersistentDataContainer container) {
-        super(null, null);
+        this(container, false);
+    }
+
+    protected NBTPersistentDataContainer(PersistentDataContainer container, boolean readOnly) {
+        super(null, null, readOnly);
         this.container = container;
     }
 

item-nbt-api/src/main/java/de/tr7zw/changeme/nbtapi/NBTReflectionUtil.java

@@ -9,8 +9,10 @@ import java.util.ArrayDeque;
 import java.util.Collections;
 import java.util.Deque;
 import java.util.Map;
+import java.util.Optional;
 import java.util.Set;
 import java.util.UUID;
+import java.util.logging.Level;
 
 import org.bukkit.Bukkit;
 import org.bukkit.block.BlockState;
@@ -18,11 +20,15 @@ import org.bukkit.entity.Entity;
 import org.bukkit.inventory.ItemStack;
 import org.bukkit.inventory.meta.ItemMeta;
 
+import com.mojang.serialization.Codec;
+import com.mojang.serialization.DynamicOps;
+
 import de.tr7zw.changeme.nbtapi.utils.DataFixerUtil;
 import de.tr7zw.changeme.nbtapi.utils.GsonWrapper;
 import de.tr7zw.changeme.nbtapi.utils.MinecraftVersion;
+import de.tr7zw.changeme.nbtapi.utils.ReflectionUtil;
 import de.tr7zw.changeme.nbtapi.utils.nmsmappings.ClassWrapper;
-import de.tr7zw.changeme.nbtapi.utils.nmsmappings.MojangToMapping;
+import de.tr7zw.changeme.nbtapi.utils.nmsmappings.CodecHelper;
 import de.tr7zw.changeme.nbtapi.utils.nmsmappings.ObjectCreator;
 import de.tr7zw.changeme.nbtapi.utils.nmsmappings.ReflectionMethod;
 
@@ -40,6 +46,10 @@ public class NBTReflectionUtil {
     private static Field field_handle = null;
     private static Object type_custom_data = null;
     private static Object registry_access = null;
+    public static Codec<Object> itemstack_codec = null;
+    public static DynamicOps<Object> nbtOps = null;
+    public static DynamicOps<Object> nbtRegistryOps = null;
+    public static Object problemReporter = null;
 
     static {
         try {
@@ -56,15 +66,22 @@ public class NBTReflectionUtil {
         }
         if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_20_R4)) {
             try {
-                Field typeField = ClassWrapper.NMS_DATACOMPONENTS.getClazz().getDeclaredField(
-                        MojangToMapping.getMapping().get("net.minecraft.core.component.DataComponents#CUSTOM_DATA"));
+                Field typeField = ReflectionUtil.getMappedField(ClassWrapper.NMS_DATACOMPONENTS.getClazz(), "net.minecraft.core.component.DataComponents#CUSTOM_DATA");
                 type_custom_data = typeField.get(null);
-            } catch (NoSuchFieldException | IllegalArgumentException | IllegalAccessException e) {
-
+            } catch (Exception e) {
+                MinecraftVersion.getLogger().log(Level.WARNING,
+                        "Unable to find DataComponents#CUSTOM_DATA, NBTApi will not be able to read/write custom data on 1.20+",
+                        e);
             }
             try {
                 Object nmsServer = ReflectionMethod.NMSSERVER_GETSERVER.run(Bukkit.getServer());
                 registry_access = ReflectionMethod.NMSSERVER_GETREGISTRYACCESS.run(nmsServer);
+                itemstack_codec = (Codec<Object>) ReflectionUtil.getMappedField(ClassWrapper.NMS_ITEMSTACK.getClazz(), "net.minecraft.world.item.ItemStack#CODEC").get(null);
+                nbtOps = (DynamicOps<Object>) ReflectionUtil.getMappedField(ClassWrapper.NMS_NBTOPS.getClazz(), "net.minecraft.nbt.NbtOps#INSTANCE").get(null);
+                if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_21_R5)) {
+                    nbtRegistryOps = (DynamicOps<Object>) ReflectionMethod.GET_SERIALIZATION_CONTEXT.run(registry_access, nbtOps);
+                    problemReporter = ReflectionUtil.getMappedField(ClassWrapper.NMS_PROBLEM_REPORTER.getClazz(), "net.minecraft.util.ProblemReporter#DISCARDING").get(null);
+                }
             } catch (Exception e) {
                 e.printStackTrace();
             }
@@ -154,7 +171,7 @@ public class NBTReflectionUtil {
     public static void writeApiNBT(NBTCompound comp, OutputStream stream) {
         try {
             Object workingtag = comp.getResolvedObject();
-            if(workingtag == null) {
+            if (workingtag == null) {
                 workingtag = ClassWrapper.NMS_NBTTAGCOMPOUND.getClazz().newInstance();
             }
             ReflectionMethod.NBTFILE_WRITE.run(null, workingtag, stream);
@@ -213,21 +230,35 @@ public class NBTReflectionUtil {
      * @return NMS ItemStack
      */
     public static Object convertNBTCompoundtoNMSItem(NBTCompound nbtcompound) {
+        Object nmsComp = null;
         try {
-            Object nmsComp = getToCompount(nbtcompound.getCompound(), nbtcompound);
+            nmsComp = getToCompount(nbtcompound.getCompound(), nbtcompound);
             if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_20_R4)) {
-                if (nbtcompound.hasTag("tag") || nbtcompound.hasTag("Count")) {
-                    nmsComp = DataFixerUtil.fixUpRawItemData(nmsComp, DataFixerUtil.VERSION1_20_4,
-                            DataFixerUtil.getCurrentVersion());
+                if (nbtcompound.hasTag("DataVersion", NBTType.NBTTagInt)) {
+                    int dataVersion = nbtcompound.getInteger("DataVersion");
+                    int currentVersion = DataFixerUtil.getCurrentVersion();
+                    if (dataVersion < currentVersion) {
+                        nmsComp = DataFixerUtil.fixUpRawItemData(nmsComp, dataVersion, currentVersion);
+                    }
+                } else if (nbtcompound.hasTag("tag") || nbtcompound.hasTag("Count")) {
+                    nmsComp = DataFixerUtil.fixUpRawItemData(nmsComp, DataFixerUtil.VERSION1_20_4, DataFixerUtil.getCurrentVersion());
+                }
+                if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_21_R5)) {
+                    return CodecHelper.convertNbtToItemStack(nmsComp);
+                } else if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_21_R4)) {
+                    Optional<Object> opt = (Optional<Object>) ReflectionMethod.NMSITEM_LOAD_MODERN.run(null,
+                            registry_access, nmsComp);
+                    return opt.orElse(null);
+                } else {
+                    return ReflectionMethod.NMSITEM_LOAD.run(null, registry_access, nmsComp);
                 }
-                return ReflectionMethod.NMSITEM_LOAD.run(null, registry_access, nmsComp);
             } else if (MinecraftVersion.getVersion().getVersionId() >= MinecraftVersion.MC1_11_R1.getVersionId()) {
                 return ObjectCreator.NMS_COMPOUNDFROMITEM.getInstance(nmsComp);
             } else {
                 return ReflectionMethod.NMSITEM_CREATESTACK.run(null, nmsComp);
             }
         } catch (Exception e) {
-            throw new NbtApiException("Exception while converting NBTCompound to NMS ItemStack!", e);
+            throw new NbtApiException("Exception while converting NBTCompound to NMS ItemStack! " + nmsComp, e);
         }
     }
 
@@ -239,13 +270,20 @@ public class NBTReflectionUtil {
      */
     public static NBTContainer convertNMSItemtoNBTCompound(Object nmsitem) {
         try {
-            if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_20_R4)) {
-                return new NBTContainer(ReflectionMethod.NMSITEM_SAVE_MODERN.run(nmsitem, registry_access));
+            NBTContainer container;
+            if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_21_R5)) {
+                container = new NBTContainer(CodecHelper.convertItemStackToNbt(nmsitem));
+            } else if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_20_R4)) {
+                container = new NBTContainer(ReflectionMethod.NMSITEM_SAVE_MODERN.run(nmsitem, registry_access));
             } else {
                 Object answer = ReflectionMethod.NMSITEM_SAVE.run(nmsitem,
                         ObjectCreator.NMS_NBTTAGCOMPOUND.getInstance());
-                return new NBTContainer(answer);
+                container = new NBTContainer(answer);
             }
+            if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_12_R1)) {
+                container.setInteger("DataVersion", DataFixerUtil.getCurrentVersion());
+            }
+            return container;
         } catch (Exception e) {
             throw new NbtApiException("Exception while converting NMS ItemStack to NBTCompound!", e);
         }
@@ -276,7 +314,16 @@ public class NBTReflectionUtil {
     public static Object getEntityNBTTagCompound(Object nmsEntity) {
         try {
             Object nbt = ClassWrapper.NMS_NBTTAGCOMPOUND.getClazz().newInstance();
-            Object answer = ReflectionMethod.NMS_ENTITY_GET_NBT.run(nmsEntity, nbt);
+            Object answer;
+            if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_21_R5)) {
+                Object output = ReflectionMethod.NMS_GET_TAG_VALUE_OUTPUT.run(null, problemReporter, registry_access);
+
+                ReflectionMethod.NMS_ENTITY_GET_NBT_1216.run(nmsEntity, output);
+
+                answer = ReflectionMethod.NMS_TAG_VALUE_OUTPUT_TO_TAG_COMPOUND.run(output);
+            } else {
+                answer = ReflectionMethod.NMS_ENTITY_GET_NBT.run(nmsEntity, nbt);
+            }
             if (answer == null)
                 answer = nbt;
             return answer;
@@ -294,7 +341,14 @@ public class NBTReflectionUtil {
      */
     public static Object setEntityNBTTag(Object nbtTag, Object nmsEntity) {
         try {
-            ReflectionMethod.NMS_ENTITY_SET_NBT.run(nmsEntity, nbtTag);
+            if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_21_R5)) {
+                Object valueInputTag = ReflectionMethod.NMS_GET_TAG_VALUE_INPUT.run(null, problemReporter, registry_access, nbtTag);
+
+                ReflectionMethod.NMS_ENTITY_SET_NBT_1216.run(nmsEntity, valueInputTag);
+            } else {
+                ReflectionMethod.NMS_ENTITY_SET_NBT.run(nmsEntity, nbtTag);
+            }
+
             return nmsEntity;
         } catch (Exception ex) {
             throw new NbtApiException("Exception while setting the NBTCompound of an Entity", ex);
@@ -326,7 +380,13 @@ public class NBTReflectionUtil {
             }
 
             Object answer = null;
-            if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_20_R4)) {
+            if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_21_R5)) {
+                Object output = ReflectionMethod.NMS_GET_TAG_VALUE_OUTPUT.run(null, problemReporter, registry_access);
+
+                ReflectionMethod.TILEENTITY_GET_NBT_1216.run(o, output);
+
+                answer = ReflectionMethod.NMS_TAG_VALUE_OUTPUT_TO_TAG_COMPOUND.run(output);
+            } else if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_20_R4)) {
                 answer = ReflectionMethod.TILEENTITY_GET_NBT_1205.run(o, registry_access);
             } else if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_18_R1)) {
                 answer = ReflectionMethod.TILEENTITY_GET_NBT_1181.run(o);
@@ -361,7 +421,11 @@ public class NBTReflectionUtil {
                 Object pos = ObjectCreator.NMS_BLOCKPOSITION.getInstance(tile.getX(), tile.getY(), tile.getZ());
                 o = ReflectionMethod.NMS_WORLD_GET_TILEENTITY.run(nmsworld, pos);
             }
-            if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_20_R4)) {
+            if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_21_R5)) {
+                Object valueInput = ReflectionMethod.NMS_GET_TAG_VALUE_INPUT.run(null, problemReporter, registry_access, comp);
+
+                ReflectionMethod.TILEENTITY_SET_NBT_1216.run(o, valueInput);
+            } else if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_20_R4)) {
                 ReflectionMethod.TILEENTITY_SET_NBT_1205.run(o, comp, registry_access);
             } else if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_17_R1)) {
                 ReflectionMethod.TILEENTITY_SET_NBT.run(o, comp);
@@ -386,7 +450,11 @@ public class NBTReflectionUtil {
     public static Object getSubNBTTagCompound(Object compound, String name) {
         try {
             if ((boolean) ReflectionMethod.COMPOUND_HAS_KEY.run(compound, name)) {
-                return ReflectionMethod.COMPOUND_GET_COMPOUND.run(compound, name);
+                Object comp = ReflectionMethod.COMPOUND_GET_COMPOUND.run(compound, name);
+                if (comp instanceof Optional) {
+                    return ((Optional<?>) comp).orElse(null);
+                }
+                return comp;
             } else {
                 throw new NbtApiException("Tried getting invalid compound '" + name + "' from '" + compound + "'!");
             }
@@ -410,7 +478,7 @@ public class NBTReflectionUtil {
         if (nbttag == null) {
             nbttag = ObjectCreator.NMS_NBTTAGCOMPOUND.getInstance();
         }
-        if (!valideCompound(comp)) {
+        if (!validCompound(comp)) {
             return;
         }
         Object workingtag = getToCompount(nbttag, comp);
@@ -427,10 +495,13 @@ public class NBTReflectionUtil {
      * Checks if the Compound is correctly linked to it's roots
      * 
      * @param comp
-     * @return true if this is a valide Compound, else false
+     * @return true if this is a valid Compound, else false
      */
-    public static boolean valideCompound(NBTCompound comp) {
+    public static boolean validCompound(NBTCompound comp) {
         Object root = comp.getCompound();
+        if (root instanceof Optional) {
+            root = ((Optional<?>) root).orElse(null);
+        }
         if (root == null) {
             root = ObjectCreator.NMS_NBTTAGCOMPOUND.getInstance();
         }
@@ -445,9 +516,15 @@ public class NBTReflectionUtil {
             structure.add(comp.getName());
             comp = comp.getParent();
         }
+        if (nbttag instanceof Optional) {
+            nbttag = ((Optional<?>) nbttag).orElse(null);
+        }
         while (!structure.isEmpty()) {
             String target = structure.pollLast();
             nbttag = getSubNBTTagCompound(nbttag, target);
+            if (nbttag instanceof Optional) {
+                nbttag = ((Optional<?>) nbttag).orElse(null);
+            }
             if (nbttag == null) {
                 throw new NbtApiException("Unable to find tag '" + target + "' in " + nbttag);
             }
@@ -470,7 +547,7 @@ public class NBTReflectionUtil {
         if (rootnbttag == null) {
             rootnbttag = ObjectCreator.NMS_NBTTAGCOMPOUND.getInstance();
         }
-        if (!valideCompound(comp))
+        if (!validCompound(comp))
             throw new NbtApiException("The Compound wasn't able to be linked back to the root!");
         Object workingtag = getToCompount(rootnbttag, comp);
         try {
@@ -497,7 +574,7 @@ public class NBTReflectionUtil {
         if (rootnbttag == null) {
             rootnbttag = ObjectCreator.NMS_NBTTAGCOMPOUND.getInstance();
         }
-        if (!valideCompound(comp)) {
+        if (!validCompound(comp)) {
             throw new NbtApiException("The Compound wasn't able to be linked back to the root!");
         }
         Object workingtag = getToCompount(rootnbttag, comp);
@@ -525,7 +602,18 @@ public class NBTReflectionUtil {
             workingtag = dummyNBT.getCompound(); // it creates a new ListTag if needed, but its unlinked
         }
         try {
-            Object nbt = ReflectionMethod.COMPOUND_GET_LIST.run(workingtag, key, type.getId());
+            Object nbt = null;
+            if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_21_R4)) {
+                nbt = ReflectionMethod.COMPOUND_GET_LIST.run(workingtag, key);
+                if (nbt instanceof Optional) {
+                    nbt = ((Optional<?>) nbt).orElse(null);
+                }
+                if (nbt == null) {
+                    nbt = ClassWrapper.NMS_NBTTAGLIST.getClazz().newInstance();
+                }
+            } else {
+                nbt = ReflectionMethod.COMPOUND_GET_LIST_LEGACY.run(workingtag, key, type.getId());
+            }
             if (clazz == String.class) {
                 return (NBTList<T>) new NBTStringList(comp, key, type, nbt);
             } else if (clazz == NBTListCompound.class) {
@@ -557,6 +645,26 @@ public class NBTReflectionUtil {
         }
         try {
             Object nbt = ReflectionMethod.COMPOUND_GET.run(workingtag, key);
+            if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_21_R4)) {
+                if (nbt instanceof Optional) {
+                    nbt = ((Optional<?>) nbt).orElse(null);
+                }
+                if (nbt == null) {
+                    return NBTType.NBTTagEnd;
+                }
+                if (new NBTStringList(comp, key, NBTType.NBTTagString, nbt).isEmpty()) {
+                    return NBTType.NBTTagEnd;
+                }
+                Object compound = ReflectionMethod.LIST_GET.run(nbt, 0);
+                if (compound instanceof Optional) {
+                    compound = ((Optional<?>) compound).orElse(null);
+                }
+                if (compound == null) {
+                    return NBTType.NBTTagEnd;
+                }
+                return NBTType.fromName((String) ReflectionMethod.TAGTYPE_GET_NAME
+                        .run(ReflectionMethod.TAGTYPE_OWN_TYPE.run(compound)));
+            }
             String fieldname = "type";
             if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_17_R1)) {
                 fieldname = "w";
@@ -631,7 +739,7 @@ public class NBTReflectionUtil {
         if (rootnbttag == null) {
             return;
         }
-        if (!valideCompound(comp))
+        if (!validCompound(comp))
             return;
         Object workingtag = getToCompount(rootnbttag, comp);
         ReflectionMethod.COMPOUND_REMOVE_KEY.run(workingtag, key);
@@ -670,7 +778,7 @@ public class NBTReflectionUtil {
         if (rootnbttag == null) {
             rootnbttag = ObjectCreator.NMS_NBTTAGCOMPOUND.getInstance();
         }
-        if (!valideCompound(comp))
+        if (!validCompound(comp))
             throw new NbtApiException("The Compound wasn't able to be linked back to the root!");
         Object workingtag = getToCompount(rootnbttag, comp);
         type.run(workingtag, key, data);
@@ -693,7 +801,41 @@ public class NBTReflectionUtil {
         if (workingtag == null) {
             workingtag = dummyNBT.getCompound();
         }
-        return type.run(workingtag, key);
+        if (workingtag instanceof Optional<?>) {
+            workingtag = ((Optional<Object>) workingtag).orElseGet(() -> dummyNBT.getCompound());
+        }
+        Object obj = type.run(workingtag, key);
+        if (obj instanceof Optional<?>) {
+            return ((Optional<Object>) obj).orElseGet(() -> getDefaultValue(type));
+        }
+        return obj;
+    }
+
+    private static Object getDefaultValue(ReflectionMethod type) {
+        if (type == ReflectionMethod.COMPOUND_GET_STRING) {
+            return "";
+        } else if (type == ReflectionMethod.COMPOUND_GET_BYTE) {
+            return (byte) 0;
+        } else if (type == ReflectionMethod.COMPOUND_GET_SHORT) {
+            return (short) 0;
+        } else if (type == ReflectionMethod.COMPOUND_GET_BOOLEAN) {
+            return false;
+        } else if (type == ReflectionMethod.COMPOUND_GET_INT) {
+            return 0;
+        } else if (type == ReflectionMethod.COMPOUND_GET_LONG) {
+            return 0L;
+        } else if (type == ReflectionMethod.COMPOUND_GET_FLOAT) {
+            return 0.0f;
+        } else if (type == ReflectionMethod.COMPOUND_GET_DOUBLE) {
+            return 0.0d;
+        } else if (type == ReflectionMethod.COMPOUND_GET_BYTEARRAY) {
+            return new byte[0];
+        } else if (type == ReflectionMethod.COMPOUND_GET_INTARRAY) {
+            return new int[0];
+        } else if (type == ReflectionMethod.COMPOUND_GET_LONGARRAY) {
+            return new long[0];
+        }
+        return null;
     }
 
 }

item-nbt-api/src/main/java/de/tr7zw/changeme/nbtapi/NBTStringList.java

@@ -2,6 +2,7 @@ package de.tr7zw.changeme.nbtapi;
 
 import java.lang.reflect.Constructor;
 import java.lang.reflect.InvocationTargetException;
+import java.util.Optional;
 
 import de.tr7zw.changeme.nbtapi.utils.nmsmappings.ClassWrapper;
 import de.tr7zw.changeme.nbtapi.utils.nmsmappings.ReflectionMethod;
@@ -21,7 +22,11 @@ public class NBTStringList extends NBTList<String> {
     @Override
     public String get(int index) {
         try {
-            return (String) ReflectionMethod.LIST_GET_STRING.run(listObject, index);
+            Object ret = ReflectionMethod.LIST_GET_STRING.run(listObject, index);
+            if (ret instanceof Optional<?>) {
+                return ((Optional<String>) ret).orElse("");
+            }
+            return (String) ret;
         } catch (Exception ex) {
             throw new NbtApiException(ex);
         }

item-nbt-api/src/main/java/de/tr7zw/changeme/nbtapi/NBTType.java

@@ -8,14 +8,16 @@ package de.tr7zw.changeme.nbtapi;
  */
 @SuppressWarnings("javadoc")
 public enum NBTType {
-    NBTTagEnd(0), NBTTagByte(1), NBTTagShort(2), NBTTagInt(3), NBTTagLong(4), NBTTagFloat(5), NBTTagDouble(6),
-    NBTTagByteArray(7), NBTTagString(8), NBTTagList(9), NBTTagCompound(10), NBTTagIntArray(11), NBTTagLongArray(12);
+    NBTTagEnd(0, ""), NBTTagByte(1, "BYTE"), NBTTagShort(2, "SHORT"), NBTTagInt(3, "INT"), NBTTagLong(4, "LONG"), NBTTagFloat(5, "FLOAT"), NBTTagDouble(6, "DOUBLE"),
+    NBTTagByteArray(7, "BYTE[]"), NBTTagString(8, "STRING"), NBTTagList(9, "LIST"), NBTTagCompound(10, "COMPOUND"), NBTTagIntArray(11, "INT[]"), NBTTagLongArray(12, "LONG[]");
 
-    NBTType(int i) {
+    NBTType(int i, String name) {
         id = i;
+        this.name = name;
     }
 
     private final int id;
+    private final String name;
 
     /**
      * @return Id used by Minecraft internally
@@ -23,6 +25,13 @@ public enum NBTType {
     public int getId() {
         return id;
     }
+    
+    /**
+     * @return Name of the NBTType
+     */
+    public String getName() {
+        return name;
+    }
 
     /**
      * @param id Internal Minecraft id
@@ -35,4 +44,11 @@ public enum NBTType {
         return NBTType.NBTTagEnd;
     }
 
+    public static NBTType fromName(String name) {
+        for (NBTType t : values())
+            if (t.getName().equals(name))
+                return t;
+        return NBTType.NBTTagEnd;
+    }
+
 }

item-nbt-api/src/main/java/de/tr7zw/changeme/nbtapi/iface/ReadableNBT.java

@@ -174,6 +174,15 @@ public interface ReadableNBT {
      */
     Set<String> getKeys();
 
+    /**
+     * Checks whether this NBT is empty (has no stored data).
+     *
+     * @return whether this NBT is empty
+     */
+    default boolean isEmpty() {
+        return getKeys().isEmpty();
+    }
+
     /**
      * @param name
      * @return The Compound instance or null
@@ -274,7 +283,7 @@ public interface ReadableNBT {
      * {@code Boolean, Byte, Short, Integer, Long, Float, Double, byte[], int[], long[]},
      * {@link String}, {@link UUID}, and {@link Enum}
      *
-     * @param key  Path key, seperated by '.'. For example: "foo.bar.baz". Dots can
+     * @param key  Path key, separated by '.'. For example: "foo.bar.baz". Dots can
      *             be escaped with a backslash.
      * @param type data type
      * @param <T>  value type
@@ -290,7 +299,7 @@ public interface ReadableNBT {
      * {@code Boolean, Byte, Short, Integer, Long, Float, Double, byte[], int[], long[]},
      * {@link String}, {@link UUID}, and {@link Enum}
      *
-     * @param key          Path key, seperated by '.'. For example: "foo.bar.baz".
+     * @param key          Path key, separated by '.'. For example: "foo.bar.baz".
      *                     Dots can be escaped with a backslash.
      * @param defaultValue default non-null value
      * @param <T>          value type
@@ -302,7 +311,7 @@ public interface ReadableNBT {
      * Returns the resolved Compound if exists, or null.
      * <p>
      * 
-     * @param key Path key, seperated by '.'. For example: "foo.bar.baz". Dots can
+     * @param key Path key, separated by '.'. For example: "foo.bar.baz". Dots can
      *            be escaped with a backslash.
      * @return The resolved value if exists, or null.
      */
@@ -344,6 +353,17 @@ public interface ReadableNBT {
      */
     void writeCompound(OutputStream stream);
 
+    /**
+     * Compares this readable nbt to the other one
+     * and returns the difference.
+     * <p>Note: the result will only contain data that is present
+     * in this readable nbt and is missing/different in the provided one.
+     *
+     * @param other other readable nbt
+     * @return difference between readable nbts
+     */
+    ReadWriteNBT extractDifference(ReadableNBT other);
+
     /**
      * @return The NBT as printable NBT-Json.
      */

item-nbt-api/src/main/java/de/tr7zw/changeme/nbtapi/utils/DataFixerUtil.java

@@ -5,42 +5,76 @@ import com.mojang.datafixers.DataFixer;
 import com.mojang.serialization.Dynamic;
 import com.mojang.serialization.DynamicOps;
 
+import de.tr7zw.changeme.nbtapi.NBT;
 import de.tr7zw.changeme.nbtapi.NBTCompound;
-import de.tr7zw.changeme.nbtapi.NBTContainer;
 import de.tr7zw.changeme.nbtapi.NBTReflectionUtil;
 import de.tr7zw.changeme.nbtapi.NbtApiException;
 import de.tr7zw.changeme.nbtapi.iface.ReadWriteNBT;
 import de.tr7zw.changeme.nbtapi.utils.nmsmappings.ClassWrapper;
-import de.tr7zw.changeme.nbtapi.utils.nmsmappings.MojangToMapping;
 import de.tr7zw.changeme.nbtapi.utils.nmsmappings.ReflectionMethod;
 
 public class DataFixerUtil {
 
-    // these values can be found in DetectedVersion inside mc
-    // Finding pre 1.12.2 values is left as an exercise for the reader, 
-    // as DetectedVersion is not a thing there
+    // https://minecraft.wiki/w/Data_version
+    public static final int VERSION1_12R1 = 1343;
+    public static final int VERSION1_16R1 = 2586;
+    public static final int VERSION1_17R1 = 2730;
+    public static final int VERSION1_18R1 = 2975;
+    public static final int VERSION1_19R1 = 3120;
+    public static final int VERSION1_19R3 = 3337;
+    public static final int VERSION1_20R1 = 3465;
+    public static final int VERSION1_20R2 = 3578;
+    public static final int VERSION1_20R3 = 3700;
+    public static final int VERSION1_20R4 = 3837;
+    public static final int VERSION1_21R1 = 3953;
+    public static final int VERSION1_21R2 = 4080;
+    public static final int VERSION1_21R3 = 4189;
+    public static final int VERSION1_21R4 = 4323;
+    public static final int VERSION1_21R5 = 4435;
+    public static final int VERSION1_21R6 = 4554;
+    public static final int VERSION1_21R7 = 4671;
+    public static final int VERSION_26_1 = 4786;
+    public static final int VERSION_26_2 = 4903;
+    public static final int VERSION_26_3 = 5023;
+    // There was a mixup between version numbers and revisions, kept for compatibility, use the above revision numbers
+    @Deprecated
     public static final int VERSION1_12_2 = 1343;
+    @Deprecated
     public static final int VERSION1_16_5 = 2586;
+    @Deprecated
     public static final int VERSION1_17_1 = 2730;
+    @Deprecated
     public static final int VERSION1_18_2 = 2975;
+    @Deprecated
     public static final int VERSION1_19_2 = 3120;
+    @Deprecated
     public static final int VERSION1_19_4 = 3337;
+    @Deprecated
     public static final int VERSION1_20_1 = 3465;
+    @Deprecated
     public static final int VERSION1_20_2 = 3578;
+    @Deprecated
     public static final int VERSION1_20_4 = 3700;
+    @Deprecated
     public static final int VERSION1_20_5 = 3837;
+    // the 1.21 versions use Revision instead of patch versions, unlike the other above. kept for compatibility
+    @Deprecated
     public static final int VERSION1_21 = 3953;
+    @Deprecated
     public static final int VERSION1_21_2 = 4080;
+    @Deprecated
+    public static final int VERSION1_21_3 = 4189;
+    @Deprecated
+    public static final int VERSION1_21_4 = 4323;
+    @Deprecated
+    public static final int VERSION1_21_5 = 4435;
 
     @SuppressWarnings("unchecked")
     public static Object fixUpRawItemData(Object nbt, int fromVersion, int toVersion)
             throws NoSuchFieldException, SecurityException, IllegalArgumentException, IllegalAccessException {
         DataFixer dataFixer = (DataFixer) ReflectionMethod.GET_DATAFIXER.run(null);
-        TypeReference itemStackReference = (TypeReference) ClassWrapper.NMS_REFERENCES.getClazz()
-                .getField(MojangToMapping.getMapping().get("net.minecraft.util.datafix.fixes.References#ITEM_STACK"))
-                .get(null);
-        DynamicOps<Object> nbtOps = (DynamicOps<Object>) ClassWrapper.NMS_NBTOPS.getClazz()
-                .getField(MojangToMapping.getMapping().get("net.minecraft.nbt.NbtOps#INSTANCE")).get(null);
+        TypeReference itemStackReference = (TypeReference) ReflectionUtil.getMappedField(ClassWrapper.NMS_REFERENCES.getClazz(),"net.minecraft.util.datafix.fixes.References#ITEM_STACK").get(null);
+        DynamicOps<Object> nbtOps = (DynamicOps<Object>) ReflectionUtil.getMappedField(ClassWrapper.NMS_NBTOPS.getClazz(), "net.minecraft.nbt.NbtOps#INSTANCE").get(null);
         Dynamic<Object> fixed = dataFixer.update(itemStackReference, new Dynamic<Object>(nbtOps, nbt), fromVersion,
                 toVersion);
         return fixed.getValue();
@@ -48,9 +82,16 @@ public class DataFixerUtil {
 
     public static ReadWriteNBT fixUpItemData(ReadWriteNBT nbt, int fromVersion, int toVersion)
             throws NoSuchFieldException, SecurityException, IllegalArgumentException, IllegalAccessException {
-        return new NBTContainer(fixUpRawItemData(
+        ReadWriteNBT tag = NBT.wrapNMSTag(fixUpRawItemData(
                 NBTReflectionUtil.getToCompount(((NBTCompound) nbt).getCompound(), ((NBTCompound) nbt)), fromVersion,
                 toVersion));
+        tag.setInteger("DataVersion", toVersion);
+        return tag;
+    }
+    
+    public static ReadWriteNBT fixUpItemData(ReadWriteNBT nbt, int fromVersion)
+            throws NoSuchFieldException, SecurityException, IllegalArgumentException, IllegalAccessException {
+        return fixUpItemData(nbt, fromVersion, getCurrentVersion());
     }
 
     /**
@@ -63,28 +104,44 @@ public class DataFixerUtil {
      * @return
      */
     public static int getCurrentVersion() {
-        if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_21_R2)) {
-            return VERSION1_21_2;
+        if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC26_3)) {
+            return VERSION_26_3;
+        } else if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC26_2)) {
+            return VERSION_26_2;
+        } else if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC26_1)) {
+            return VERSION_26_1;
+        } else if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_21_R7)) {
+            return VERSION1_21R7;
+        } else if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_21_R6)) {
+            return VERSION1_21R6;
+        } else if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_21_R5)) {
+            return VERSION1_21R5;
+        } else if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_21_R4)) {
+            return VERSION1_21R4;
+        } else if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_21_R3)) {
+            return VERSION1_21R3;
+        } else if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_21_R2)) {
+            return VERSION1_21R2;
         } else if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_21_R1)) {
-            return VERSION1_21;
+            return VERSION1_21R1;
         } else if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_20_R4)) {
-            return VERSION1_20_5;
+            return VERSION1_20R4;
         } else if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_20_R3)) {
-            return VERSION1_20_4;
+            return VERSION1_20R3;
         } else if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_20_R1)) {
-            return VERSION1_20_1;
+            return VERSION1_20R1;
         } else if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_19_R3)) {
-            return VERSION1_19_4;
+            return VERSION1_19R3;
         } else if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_19_R1)) {
-            return VERSION1_19_2;
+            return VERSION1_19R1;
         } else if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_18_R1)) {
-            return VERSION1_18_2;
+            return VERSION1_18R1;
         } else if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_17_R1)) {
-            return VERSION1_17_1;
+            return VERSION1_17R1;
         } else if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_16_R1)) {
-            return VERSION1_16_5;
+            return VERSION1_16R1;
         } else if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_12_R1)) {
-            return VERSION1_12_2;
+            return VERSION1_12R1;
         }
         throw new NbtApiException(
                 "Trying to update data *to* a version before 1.12.2? Something is probably going wrong, contact the plugin author.");

item-nbt-api/src/main/java/de/tr7zw/changeme/nbtapi/utils/GameprofileUtil.java

@@ -1,12 +1,16 @@
 package de.tr7zw.changeme.nbtapi.utils;
 
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
 import java.util.UUID;
 
 import javax.annotation.Nullable;
 
 import com.mojang.authlib.GameProfile;
+import com.mojang.authlib.properties.PropertyMap;
 
 import de.tr7zw.changeme.nbtapi.NBTType;
+import de.tr7zw.changeme.nbtapi.NbtApiException;
 import de.tr7zw.changeme.nbtapi.iface.ReadWriteNBT;
 import de.tr7zw.changeme.nbtapi.iface.ReadWriteNBTCompoundList;
 import de.tr7zw.changeme.nbtapi.iface.ReadableNBT;
@@ -14,15 +18,42 @@ import de.tr7zw.changeme.nbtapi.iface.ReadableNBTList;
 
 public class GameprofileUtil {
 
+    private static Method GET_NAME = null;
+    private static Method GET_ID = null;
+    private static Method GET_VALUE = null;
+    private static Method GET_SIGNATURE = null;
+    private static Method GET_PROPERTY_NAME = null;
+    private static Method GET_PROPERTIES = null;
+    
+    static {
+        if(MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_21_R6)) {
+            try {
+                GET_NAME = GameProfile.class.getDeclaredMethod("name");
+                GET_ID = GameProfile.class.getDeclaredMethod("id");
+                GET_VALUE = com.mojang.authlib.properties.Property.class.getDeclaredMethod("value");
+                GET_SIGNATURE = com.mojang.authlib.properties.Property.class.getDeclaredMethod("signature");
+                GET_PROPERTY_NAME = com.mojang.authlib.properties.Property.class.getDeclaredMethod("name");
+                GET_PROPERTIES = GameProfile.class.getDeclaredMethod("properties");
+            } catch (NoSuchMethodException e) {
+                e.printStackTrace();
+            }
+        }
+    }
+    
     @Nullable
     public static GameProfile readGameProfile(ReadableNBT arg) {
         String string = null;
         UUID uUID = null;
         if (arg.hasTag("Name") && arg.getType("Name") == NBTType.NBTTagString) {
             string = arg.getString("Name");
+        } else if (arg.hasTag("name") && arg.getType("name") == NBTType.NBTTagString) {
+            string = arg.getString("name");
         }
         if (arg.hasTag("Id") && arg.getType("Id") == NBTType.NBTTagIntArray && arg.getIntArray("Id").length == 4) {
             uUID = arg.getUUID("Id");
+        } else if (arg.hasTag("id") && arg.getType("id") == NBTType.NBTTagIntArray
+                && arg.getIntArray("id").length == 4) {
+            uUID = arg.getUUID("id");
         }
         try {
             GameProfile gameProfile = new GameProfile(uUID, string);
@@ -43,6 +74,21 @@ public class GameprofileUtil {
                         }
                     }
                 }
+            } else if (arg.getType("properties") == NBTType.NBTTagList) { // 1.20.5+
+                ReadableNBTList<ReadWriteNBT> listTag = arg.getCompoundList("properties");
+                for (int i = 0; i < listTag.size(); ++i) {
+                    ReadableNBT compoundTag2 = listTag.get(i);
+                    String string2 = compoundTag2.getString("name");
+                    String string3 = compoundTag2.getString("value");
+                    if (compoundTag2.hasTag("signature")
+                            && compoundTag2.getType("signature") == NBTType.NBTTagString) {
+                        gameProfile.getProperties().put(string2, new com.mojang.authlib.properties.Property(string2,
+                                string3, compoundTag2.getString("signature")));
+                    } else {
+                        gameProfile.getProperties().put(string2,
+                                new com.mojang.authlib.properties.Property(string2, string3));
+                    }
+                }
             }
             return gameProfile;
         } catch (Throwable var11) {
@@ -51,26 +97,115 @@ public class GameprofileUtil {
     }
 
     public static ReadWriteNBT writeGameProfile(ReadWriteNBT arg, GameProfile gameProfile) {
-        if (!(gameProfile.getName() == null || gameProfile.getName().isEmpty())) {
-            arg.setString("Name", gameProfile.getName());
+        String name = getName(gameProfile);
+        if (!(name == null || name.isEmpty())) {
+            String nameKey = MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_20_R4) ? "name" : "Name";
+            arg.setString(nameKey, getName(gameProfile));
         }
-        if (gameProfile.getId() != null) {
-            arg.setUUID("Id", gameProfile.getId());
+        UUID id = getId(gameProfile);
+        if (id != null) {
+            String idKey = MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_20_R4) ? "id" : "Id";
+            arg.setUUID(idKey, id);
         }
-        if (!gameProfile.getProperties().isEmpty()) {
-            ReadWriteNBT compoundTag = arg.getOrCreateCompound("Properties");
-            for (String string : gameProfile.getProperties().keySet()) {
-                ReadWriteNBTCompoundList list = compoundTag.getCompoundList(string);
-                for (com.mojang.authlib.properties.Property property : gameProfile.getProperties().get(string)) {
-                    ReadWriteNBT tag = list.addCompound();
-                    tag.setString("Value", property.getValue());
-                    if (property.hasSignature()) {
-                        tag.setString("Signature", property.getSignature());
+        PropertyMap properties = getProperties(gameProfile);
+        if (!properties.isEmpty()) {
+            if(MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_20_R4)) {
+                    ReadWriteNBTCompoundList list = arg.getCompoundList("properties");
+                    for (com.mojang.authlib.properties.Property property : properties.values()) {
+                        ReadWriteNBT tag = list.addCompound();
+                        tag.setString("name", getPropertyName(property));
+                        tag.setString("value", getValue(property));
+                        if (property.hasSignature()) {
+                            tag.setString("signature", getSignature(property));
+                        }
+                }
+            } else {
+                ReadWriteNBT compoundTag = arg.getOrCreateCompound("Properties");
+                for (String string : gameProfile.getProperties().keySet()) {
+                    ReadWriteNBTCompoundList list = compoundTag.getCompoundList(string);
+                    for (com.mojang.authlib.properties.Property property : properties.get(string)) {
+                        ReadWriteNBT tag = list.addCompound();
+                        tag.setString("Value", getValue(property));
+                        if (property.hasSignature()) {
+                            tag.setString("Signature", getSignature(property));
+                        }
                     }
                 }
             }
         }
         return arg;
     }
+    
+    private static String getName(GameProfile profile) {
+        if(MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_21_R6)) {
+            try {
+                return GET_NAME.invoke(profile).toString();
+            } catch (IllegalAccessException | IllegalArgumentException | InvocationTargetException e) {
+                throw new NbtApiException("Failed to get GameProfile name via reflection", e);
+            }
+        } else {
+            return profile.getName();
+        }
+    }
+    
+    private static UUID getId(GameProfile profile) {
+        if(MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_21_R6)) {
+            try {
+                return (UUID) GET_ID.invoke(profile);
+            } catch (IllegalAccessException | IllegalArgumentException | InvocationTargetException e) {
+                throw new NbtApiException("Failed to get GameProfile id via reflection", e);
+            }
+        } else {
+            return profile.getId();
+        }
+    }
+    
+    private static String getValue(com.mojang.authlib.properties.Property property) {
+        if(MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_21_R6)) {
+            try {
+                return GET_VALUE.invoke(property).toString();
+            } catch (IllegalAccessException | IllegalArgumentException | InvocationTargetException e) {
+                throw new NbtApiException("Failed to get Property value via reflection", e);
+            }
+        } else {
+            return property.getValue();
+        }
+    }
+    
+    private static String getSignature(com.mojang.authlib.properties.Property property) {
+        if(MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_21_R6)) {
+            try {
+                return GET_SIGNATURE.invoke(property).toString();
+            } catch (IllegalAccessException | IllegalArgumentException | InvocationTargetException e) {
+                throw new NbtApiException("Failed to get Property signature via reflection", e);
+            }
+        } else {
+            return property.getSignature();
+        }
+    }
+    
+    private static String getPropertyName(com.mojang.authlib.properties.Property property) {
+        if(MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_21_R6)) {
+            try {
+                return GET_PROPERTY_NAME.invoke(property).toString();
+            } catch (IllegalAccessException | IllegalArgumentException | InvocationTargetException e) {
+                throw new NbtApiException("Failed to get Property name via reflection", e);
+            }
+        } else {
+            return property.getName();
+        }
+    }
+    
+    private static PropertyMap getProperties(GameProfile profile) {
+        if(MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_21_R6)) {
+            try {
+                return (PropertyMap) GET_PROPERTIES.invoke(profile);
+            } catch (IllegalAccessException | IllegalArgumentException | InvocationTargetException e) {
+                throw new NbtApiException("Failed to get GameProfile properties via reflection", e);
+            }
+        } else {
+            return profile.getProperties();
+        }
+    }
 
 }

item-nbt-api/src/main/java/de/tr7zw/changeme/nbtapi/utils/Metrics.java

@@ -1,881 +0,0 @@
-/*
- * This Metrics class was auto-generated and can be copied into your project if you are
- * not using a build tool like Gradle or Maven for dependency management.
- *
- * IMPORTANT: You are not allowed to modify this class, except changing the package.
- *
- * Disallowed modifications include but are not limited to:
- *  - Remove the option for users to opt-out
- *  - Change the frequency for data submission
- *  - Obfuscate the code (every obfuscator should allow you to make an exception for specific files)
- *  - Reformat the code (if you use a linter, add an exception)
- *
- * Violations will result in a ban of your plugin and account from bStats.
- */
-package de.tr7zw.changeme.nbtapi.utils;
-
-import java.io.BufferedReader;
-import java.io.ByteArrayOutputStream;
-import java.io.DataOutputStream;
-import java.io.File;
-import java.io.IOException;
-import java.io.InputStreamReader;
-import java.lang.reflect.Method;
-import java.net.URL;
-import java.nio.charset.StandardCharsets;
-import java.util.Arrays;
-import java.util.Collection;
-import java.util.HashSet;
-import java.util.Map;
-import java.util.Objects;
-import java.util.Set;
-import java.util.UUID;
-import java.util.concurrent.Callable;
-import java.util.concurrent.ScheduledExecutorService;
-import java.util.concurrent.ScheduledThreadPoolExecutor;
-import java.util.concurrent.TimeUnit;
-import java.util.function.BiConsumer;
-import java.util.function.Consumer;
-import java.util.function.Supplier;
-import java.util.logging.Level;
-import java.util.stream.Collectors;
-import java.util.zip.GZIPOutputStream;
-import javax.net.ssl.HttpsURLConnection;
-import org.bukkit.Bukkit;
-import org.bukkit.configuration.file.YamlConfiguration;
-import org.bukkit.entity.Player;
-import org.bukkit.plugin.Plugin;
-import org.bukkit.plugin.java.JavaPlugin;
-
-public class Metrics {
-
-  private final Plugin plugin;
-
-  private final MetricsBase metricsBase;
-
-  /**
-   * Creates a new Metrics instance.
-   *
-   * @param plugin Your plugin instance.
-   * @param serviceId The id of the service. It can be found at <a
-   *     href="https://bstats.org/what-is-my-plugin-id">What is my plugin id?</a>
-   */
-  public Metrics(JavaPlugin plugin, int serviceId) {
-    this.plugin = plugin;
-    // Get the config file
-    File bStatsFolder = new File(plugin.getDataFolder().getParentFile(), "bStats");
-    File configFile = new File(bStatsFolder, "config.yml");
-    YamlConfiguration config = YamlConfiguration.loadConfiguration(configFile);
-    if (!config.isSet("serverUuid")) {
-      config.addDefault("enabled", true);
-      config.addDefault("serverUuid", UUID.randomUUID().toString());
-      config.addDefault("logFailedRequests", false);
-      config.addDefault("logSentData", false);
-      config.addDefault("logResponseStatusText", false);
-      // Inform the server owners about bStats
-      config
-          .options()
-          .header(
-              "bStats (https://bStats.org) collects some basic information for plugin authors, like how\n"
-                  + "many people use their plugin and their total player count. It's recommended to keep bStats\n"
-                  + "enabled, but if you're not comfortable with this, you can turn this setting off. There is no\n"
-                  + "performance penalty associated with having metrics enabled, and data sent to bStats is fully\n"
-                  + "anonymous.")
-          .copyDefaults(true);
-      try {
-        config.save(configFile);
-      } catch (IOException ignored) {
-      }
-    }
-    // Load the data
-    boolean enabled = config.getBoolean("enabled", true);
-    String serverUUID = config.getString("serverUuid");
-    boolean logErrors = config.getBoolean("logFailedRequests", false);
-    boolean logSentData = config.getBoolean("logSentData", false);
-    boolean logResponseStatusText = config.getBoolean("logResponseStatusText", false);
-    metricsBase =
-        new MetricsBase(
-            "bukkit",
-            serverUUID,
-            serviceId,
-            enabled,
-            this::appendPlatformData,
-            this::appendServiceData,
-            submitDataTask -> Bukkit.getScheduler().runTask(plugin, submitDataTask),
-            plugin::isEnabled,
-            (message, error) -> this.plugin.getLogger().log(Level.WARNING, message, error),
-            (message) -> this.plugin.getLogger().log(Level.INFO, message),
-            logErrors,
-            logSentData,
-            logResponseStatusText);
-  }
-
-  /** Shuts down the underlying scheduler service. */
-  public void shutdown() {
-    metricsBase.shutdown();
-  }
-
-  /**
-   * Adds a custom chart.
-   *
-   * @param chart The chart to add.
-   */
-  public void addCustomChart(CustomChart chart) {
-    metricsBase.addCustomChart(chart);
-  }
-
-  private void appendPlatformData(JsonObjectBuilder builder) {
-    builder.appendField("playerAmount", getPlayerAmount());
-    builder.appendField("onlineMode", Bukkit.getOnlineMode() ? 1 : 0);
-    builder.appendField("bukkitVersion", Bukkit.getVersion());
-    builder.appendField("bukkitName", Bukkit.getName());
-    builder.appendField("javaVersion", System.getProperty("java.version"));
-    builder.appendField("osName", System.getProperty("os.name"));
-    builder.appendField("osArch", System.getProperty("os.arch"));
-    builder.appendField("osVersion", System.getProperty("os.version"));
-    builder.appendField("coreCount", Runtime.getRuntime().availableProcessors());
-  }
-
-  private void appendServiceData(JsonObjectBuilder builder) {
-    builder.appendField("pluginVersion", plugin.getDescription().getVersion());
-  }
-
-  private int getPlayerAmount() {
-    try {
-      // Around MC 1.8 the return type was changed from an array to a collection,
-      // This fixes java.lang.NoSuchMethodError:
-      // org.bukkit.Bukkit.getOnlinePlayers()Ljava/util/Collection;
-      Method onlinePlayersMethod = Class.forName("org.bukkit.Server").getMethod("getOnlinePlayers");
-      return onlinePlayersMethod.getReturnType().equals(Collection.class)
-          ? ((Collection<?>) onlinePlayersMethod.invoke(Bukkit.getServer())).size()
-          : ((Player[]) onlinePlayersMethod.invoke(Bukkit.getServer())).length;
-    } catch (Exception e) {
-      // Just use the new method if the reflection failed
-      return Bukkit.getOnlinePlayers().size();
-    }
-  }
-
-  public static class MetricsBase {
-
-    /** The version of the Metrics class. */
-    public static final String METRICS_VERSION = "3.0.2";
-
-    private static final String REPORT_URL = "https://bStats.org/api/v2/data/%s";
-
-    private final ScheduledExecutorService scheduler;
-
-    private final String platform;
-
-    private final String serverUuid;
-
-    private final int serviceId;
-
-    private final Consumer<JsonObjectBuilder> appendPlatformDataConsumer;
-
-    private final Consumer<JsonObjectBuilder> appendServiceDataConsumer;
-
-    private final Consumer<Runnable> submitTaskConsumer;
-
-    private final Supplier<Boolean> checkServiceEnabledSupplier;
-
-    private final BiConsumer<String, Throwable> errorLogger;
-
-    private final Consumer<String> infoLogger;
-
-    private final boolean logErrors;
-
-    private final boolean logSentData;
-
-    private final boolean logResponseStatusText;
-
-    private final Set<CustomChart> customCharts = new HashSet<>();
-
-    private final boolean enabled;
-
-    /**
-     * Creates a new MetricsBase class instance.
-     *
-     * @param platform The platform of the service.
-     * @param serviceId The id of the service.
-     * @param serverUuid The server uuid.
-     * @param enabled Whether or not data sending is enabled.
-     * @param appendPlatformDataConsumer A consumer that receives a {@code JsonObjectBuilder} and
-     *     appends all platform-specific data.
-     * @param appendServiceDataConsumer A consumer that receives a {@code JsonObjectBuilder} and
-     *     appends all service-specific data.
-     * @param submitTaskConsumer A consumer that takes a runnable with the submit task. This can be
-     *     used to delegate the data collection to a another thread to prevent errors caused by
-     *     concurrency. Can be {@code null}.
-     * @param checkServiceEnabledSupplier A supplier to check if the service is still enabled.
-     * @param errorLogger A consumer that accepts log message and an error.
-     * @param infoLogger A consumer that accepts info log messages.
-     * @param logErrors Whether or not errors should be logged.
-     * @param logSentData Whether or not the sent data should be logged.
-     * @param logResponseStatusText Whether or not the response status text should be logged.
-     */
-    public MetricsBase(
-        String platform,
-        String serverUuid,
-        int serviceId,
-        boolean enabled,
-        Consumer<JsonObjectBuilder> appendPlatformDataConsumer,
-        Consumer<JsonObjectBuilder> appendServiceDataConsumer,
-        Consumer<Runnable> submitTaskConsumer,
-        Supplier<Boolean> checkServiceEnabledSupplier,
-        BiConsumer<String, Throwable> errorLogger,
-        Consumer<String> infoLogger,
-        boolean logErrors,
-        boolean logSentData,
-        boolean logResponseStatusText) {
-      ScheduledThreadPoolExecutor scheduler =
-          new ScheduledThreadPoolExecutor(1, task -> new Thread(task, "bStats-Metrics"));
-      // We want delayed tasks (non-periodic) that will execute in the future to be
-      // cancelled when the scheduler is shutdown.
-      // Otherwise, we risk preventing the server from shutting down even when
-      // MetricsBase#shutdown() is called
-      scheduler.setExecuteExistingDelayedTasksAfterShutdownPolicy(false);
-      this.scheduler = scheduler;
-      this.platform = platform;
-      this.serverUuid = serverUuid;
-      this.serviceId = serviceId;
-      this.enabled = enabled;
-      this.appendPlatformDataConsumer = appendPlatformDataConsumer;
-      this.appendServiceDataConsumer = appendServiceDataConsumer;
-      this.submitTaskConsumer = submitTaskConsumer;
-      this.checkServiceEnabledSupplier = checkServiceEnabledSupplier;
-      this.errorLogger = errorLogger;
-      this.infoLogger = infoLogger;
-      this.logErrors = logErrors;
-      this.logSentData = logSentData;
-      this.logResponseStatusText = logResponseStatusText;
-      checkRelocation();
-      if (enabled) {
-        // WARNING: Removing the option to opt-out will get your plugin banned from
-        // bStats
-        startSubmitting();
-      }
-    }
-
-    public void addCustomChart(CustomChart chart) {
-      this.customCharts.add(chart);
-    }
-
-    public void shutdown() {
-      scheduler.shutdown();
-    }
-
-    private void startSubmitting() {
-      final Runnable submitTask =
-          () -> {
-            if (!enabled || !checkServiceEnabledSupplier.get()) {
-              // Submitting data or service is disabled
-              scheduler.shutdown();
-              return;
-            }
-            if (submitTaskConsumer != null) {
-              submitTaskConsumer.accept(this::submitData);
-            } else {
-              this.submitData();
-            }
-          };
-      // Many servers tend to restart at a fixed time at xx:00 which causes an uneven
-      // distribution of requests on the
-      // bStats backend. To circumvent this problem, we introduce some randomness into
-      // the initial and second delay.
-      // WARNING: You must not modify and part of this Metrics class, including the
-      // submit delay or frequency!
-      // WARNING: Modifying this code will get your plugin banned on bStats. Just
-      // don't do it!
-      long initialDelay = (long) (1000 * 60 * (3 + Math.random() * 3));
-      long secondDelay = (long) (1000 * 60 * (Math.random() * 30));
-      scheduler.schedule(submitTask, initialDelay, TimeUnit.MILLISECONDS);
-      scheduler.scheduleAtFixedRate(
-          submitTask, initialDelay + secondDelay, 1000 * 60 * 30, TimeUnit.MILLISECONDS);
-    }
-
-    private void submitData() {
-      final JsonObjectBuilder baseJsonBuilder = new JsonObjectBuilder();
-      appendPlatformDataConsumer.accept(baseJsonBuilder);
-      final JsonObjectBuilder serviceJsonBuilder = new JsonObjectBuilder();
-      appendServiceDataConsumer.accept(serviceJsonBuilder);
-      JsonObjectBuilder.JsonObject[] chartData =
-          customCharts.stream()
-              .map(customChart -> customChart.getRequestJsonObject(errorLogger, logErrors))
-              .filter(Objects::nonNull)
-              .toArray(JsonObjectBuilder.JsonObject[]::new);
-      serviceJsonBuilder.appendField("id", serviceId);
-      serviceJsonBuilder.appendField("customCharts", chartData);
-      baseJsonBuilder.appendField("service", serviceJsonBuilder.build());
-      baseJsonBuilder.appendField("serverUUID", serverUuid);
-      baseJsonBuilder.appendField("metricsVersion", METRICS_VERSION);
-      JsonObjectBuilder.JsonObject data = baseJsonBuilder.build();
-      scheduler.execute(
-          () -> {
-            try {
-              // Send the data
-              sendData(data);
-            } catch (Exception e) {
-              // Something went wrong! :(
-              if (logErrors) {
-                errorLogger.accept("Could not submit bStats metrics data", e);
-              }
-            }
-          });
-    }
-
-    private void sendData(JsonObjectBuilder.JsonObject data) throws Exception {
-      if (logSentData) {
-        infoLogger.accept("Sent bStats metrics data: " + data.toString());
-      }
-      String url = String.format(REPORT_URL, platform);
-      HttpsURLConnection connection = (HttpsURLConnection) new URL(url).openConnection();
-      // Compress the data to save bandwidth
-      byte[] compressedData = compress(data.toString());
-      connection.setRequestMethod("POST");
-      connection.addRequestProperty("Accept", "application/json");
-      connection.addRequestProperty("Connection", "close");
-      connection.addRequestProperty("Content-Encoding", "gzip");
-      connection.addRequestProperty("Content-Length", String.valueOf(compressedData.length));
-      connection.setRequestProperty("Content-Type", "application/json");
-      connection.setRequestProperty("User-Agent", "Metrics-Service/1");
-      connection.setDoOutput(true);
-      try (DataOutputStream outputStream = new DataOutputStream(connection.getOutputStream())) {
-        outputStream.write(compressedData);
-      }
-      StringBuilder builder = new StringBuilder();
-      try (BufferedReader bufferedReader =
-          new BufferedReader(new InputStreamReader(connection.getInputStream()))) {
-        String line;
-        while ((line = bufferedReader.readLine()) != null) {
-          builder.append(line);
-        }
-      }
-      if (logResponseStatusText) {
-        infoLogger.accept("Sent data to bStats and received response: " + builder);
-      }
-    }
-
-    /** Checks that the class was properly relocated. */
-    private void checkRelocation() {
-      // You can use the property to disable the check in your test environment
-      if (System.getProperty("bstats.relocatecheck") == null
-          || !System.getProperty("bstats.relocatecheck").equals("false")) {
-        // Maven's Relocate is clever and changes strings, too. So we have to use this
-        // little "trick" ... :D
-        final String defaultPackage =
-            new String(new byte[] {'o', 'r', 'g', '.', 'b', 's', 't', 'a', 't', 's'});
-        final String examplePackage =
-            new String(new byte[] {'y', 'o', 'u', 'r', '.', 'p', 'a', 'c', 'k', 'a', 'g', 'e'});
-        // We want to make sure no one just copy & pastes the example and uses the wrong
-        // package names
-        if (MetricsBase.class.getPackage().getName().startsWith(defaultPackage)
-            || MetricsBase.class.getPackage().getName().startsWith(examplePackage)) {
-          throw new IllegalStateException("bStats Metrics class has not been relocated correctly!");
-        }
-      }
-    }
-
-    /**
-     * Gzips the given string.
-     *
-     * @param str The string to gzip.
-     * @return The gzipped string.
-     */
-    private static byte[] compress(final String str) throws IOException {
-      if (str == null) {
-        return null;
-      }
-      ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
-      try (GZIPOutputStream gzip = new GZIPOutputStream(outputStream)) {
-        gzip.write(str.getBytes(StandardCharsets.UTF_8));
-      }
-      return outputStream.toByteArray();
-    }
-  }
-
-  public static class SimplePie extends CustomChart {
-
-    private final Callable<String> callable;
-
-    /**
-     * Class constructor.
-     *
-     * @param chartId The id of the chart.
-     * @param callable The callable which is used to request the chart data.
-     */
-    public SimplePie(String chartId, Callable<String> callable) {
-      super(chartId);
-      this.callable = callable;
-    }
-
-    @Override
-    protected JsonObjectBuilder.JsonObject getChartData() throws Exception {
-      String value = callable.call();
-      if (value == null || value.isEmpty()) {
-        // Null = skip the chart
-        return null;
-      }
-      return new JsonObjectBuilder().appendField("value", value).build();
-    }
-  }
-
-  public static class MultiLineChart extends CustomChart {
-
-    private final Callable<Map<String, Integer>> callable;
-
-    /**
-     * Class constructor.
-     *
-     * @param chartId The id of the chart.
-     * @param callable The callable which is used to request the chart data.
-     */
-    public MultiLineChart(String chartId, Callable<Map<String, Integer>> callable) {
-      super(chartId);
-      this.callable = callable;
-    }
-
-    @Override
-    protected JsonObjectBuilder.JsonObject getChartData() throws Exception {
-      JsonObjectBuilder valuesBuilder = new JsonObjectBuilder();
-      Map<String, Integer> map = callable.call();
-      if (map == null || map.isEmpty()) {
-        // Null = skip the chart
-        return null;
-      }
-      boolean allSkipped = true;
-      for (Map.Entry<String, Integer> entry : map.entrySet()) {
-        if (entry.getValue() == 0) {
-          // Skip this invalid
-          continue;
-        }
-        allSkipped = false;
-        valuesBuilder.appendField(entry.getKey(), entry.getValue());
-      }
-      if (allSkipped) {
-        // Null = skip the chart
-        return null;
-      }
-      return new JsonObjectBuilder().appendField("values", valuesBuilder.build()).build();
-    }
-  }
-
-  public static class AdvancedPie extends CustomChart {
-
-    private final Callable<Map<String, Integer>> callable;
-
-    /**
-     * Class constructor.
-     *
-     * @param chartId The id of the chart.
-     * @param callable The callable which is used to request the chart data.
-     */
-    public AdvancedPie(String chartId, Callable<Map<String, Integer>> callable) {
-      super(chartId);
-      this.callable = callable;
-    }
-
-    @Override
-    protected JsonObjectBuilder.JsonObject getChartData() throws Exception {
-      JsonObjectBuilder valuesBuilder = new JsonObjectBuilder();
-      Map<String, Integer> map = callable.call();
-      if (map == null || map.isEmpty()) {
-        // Null = skip the chart
-        return null;
-      }
-      boolean allSkipped = true;
-      for (Map.Entry<String, Integer> entry : map.entrySet()) {
-        if (entry.getValue() == 0) {
-          // Skip this invalid
-          continue;
-        }
-        allSkipped = false;
-        valuesBuilder.appendField(entry.getKey(), entry.getValue());
-      }
-      if (allSkipped) {
-        // Null = skip the chart
-        return null;
-      }
-      return new JsonObjectBuilder().appendField("values", valuesBuilder.build()).build();
-    }
-  }
-
-  public static class SimpleBarChart extends CustomChart {
-
-    private final Callable<Map<String, Integer>> callable;
-
-    /**
-     * Class constructor.
-     *
-     * @param chartId The id of the chart.
-     * @param callable The callable which is used to request the chart data.
-     */
-    public SimpleBarChart(String chartId, Callable<Map<String, Integer>> callable) {
-      super(chartId);
-      this.callable = callable;
-    }
-
-    @Override
-    protected JsonObjectBuilder.JsonObject getChartData() throws Exception {
-      JsonObjectBuilder valuesBuilder = new JsonObjectBuilder();
-      Map<String, Integer> map = callable.call();
-      if (map == null || map.isEmpty()) {
-        // Null = skip the chart
-        return null;
-      }
-      for (Map.Entry<String, Integer> entry : map.entrySet()) {
-        valuesBuilder.appendField(entry.getKey(), new int[] {entry.getValue()});
-      }
-      return new JsonObjectBuilder().appendField("values", valuesBuilder.build()).build();
-    }
-  }
-
-  public static class AdvancedBarChart extends CustomChart {
-
-    private final Callable<Map<String, int[]>> callable;
-
-    /**
-     * Class constructor.
-     *
-     * @param chartId The id of the chart.
-     * @param callable The callable which is used to request the chart data.
-     */
-    public AdvancedBarChart(String chartId, Callable<Map<String, int[]>> callable) {
-      super(chartId);
-      this.callable = callable;
-    }
-
-    @Override
-    protected JsonObjectBuilder.JsonObject getChartData() throws Exception {
-      JsonObjectBuilder valuesBuilder = new JsonObjectBuilder();
-      Map<String, int[]> map = callable.call();
-      if (map == null || map.isEmpty()) {
-        // Null = skip the chart
-        return null;
-      }
-      boolean allSkipped = true;
-      for (Map.Entry<String, int[]> entry : map.entrySet()) {
-        if (entry.getValue().length == 0) {
-          // Skip this invalid
-          continue;
-        }
-        allSkipped = false;
-        valuesBuilder.appendField(entry.getKey(), entry.getValue());
-      }
-      if (allSkipped) {
-        // Null = skip the chart
-        return null;
-      }
-      return new JsonObjectBuilder().appendField("values", valuesBuilder.build()).build();
-    }
-  }
-
-  public static class DrilldownPie extends CustomChart {
-
-    private final Callable<Map<String, Map<String, Integer>>> callable;
-
-    /**
-     * Class constructor.
-     *
-     * @param chartId The id of the chart.
-     * @param callable The callable which is used to request the chart data.
-     */
-    public DrilldownPie(String chartId, Callable<Map<String, Map<String, Integer>>> callable) {
-      super(chartId);
-      this.callable = callable;
-    }
-
-    @Override
-    public JsonObjectBuilder.JsonObject getChartData() throws Exception {
-      JsonObjectBuilder valuesBuilder = new JsonObjectBuilder();
-      Map<String, Map<String, Integer>> map = callable.call();
-      if (map == null || map.isEmpty()) {
-        // Null = skip the chart
-        return null;
-      }
-      boolean reallyAllSkipped = true;
-      for (Map.Entry<String, Map<String, Integer>> entryValues : map.entrySet()) {
-        JsonObjectBuilder valueBuilder = new JsonObjectBuilder();
-        boolean allSkipped = true;
-        for (Map.Entry<String, Integer> valueEntry : map.get(entryValues.getKey()).entrySet()) {
-          valueBuilder.appendField(valueEntry.getKey(), valueEntry.getValue());
-          allSkipped = false;
-        }
-        if (!allSkipped) {
-          reallyAllSkipped = false;
-          valuesBuilder.appendField(entryValues.getKey(), valueBuilder.build());
-        }
-      }
-      if (reallyAllSkipped) {
-        // Null = skip the chart
-        return null;
-      }
-      return new JsonObjectBuilder().appendField("values", valuesBuilder.build()).build();
-    }
-  }
-
-  public abstract static class CustomChart {
-
-    private final String chartId;
-
-    protected CustomChart(String chartId) {
-      if (chartId == null) {
-        throw new IllegalArgumentException("chartId must not be null");
-      }
-      this.chartId = chartId;
-    }
-
-    public JsonObjectBuilder.JsonObject getRequestJsonObject(
-        BiConsumer<String, Throwable> errorLogger, boolean logErrors) {
-      JsonObjectBuilder builder = new JsonObjectBuilder();
-      builder.appendField("chartId", chartId);
-      try {
-        JsonObjectBuilder.JsonObject data = getChartData();
-        if (data == null) {
-          // If the data is null we don't send the chart.
-          return null;
-        }
-        builder.appendField("data", data);
-      } catch (Throwable t) {
-        if (logErrors) {
-          errorLogger.accept("Failed to get data for custom chart with id " + chartId, t);
-        }
-        return null;
-      }
-      return builder.build();
-    }
-
-    protected abstract JsonObjectBuilder.JsonObject getChartData() throws Exception;
-  }
-
-  public static class SingleLineChart extends CustomChart {
-
-    private final Callable<Integer> callable;
-
-    /**
-     * Class constructor.
-     *
-     * @param chartId The id of the chart.
-     * @param callable The callable which is used to request the chart data.
-     */
-    public SingleLineChart(String chartId, Callable<Integer> callable) {
-      super(chartId);
-      this.callable = callable;
-    }
-
-    @Override
-    protected JsonObjectBuilder.JsonObject getChartData() throws Exception {
-      int value = callable.call();
-      if (value == 0) {
-        // Null = skip the chart
-        return null;
-      }
-      return new JsonObjectBuilder().appendField("value", value).build();
-    }
-  }
-
-  /**
-   * An extremely simple JSON builder.
-   *
-   * <p>While this class is neither feature-rich nor the most performant one, it's sufficient enough
-   * for its use-case.
-   */
-  public static class JsonObjectBuilder {
-
-    private StringBuilder builder = new StringBuilder();
-
-    private boolean hasAtLeastOneField = false;
-
-    public JsonObjectBuilder() {
-      builder.append("{");
-    }
-
-    /**
-     * Appends a null field to the JSON.
-     *
-     * @param key The key of the field.
-     * @return A reference to this object.
-     */
-    public JsonObjectBuilder appendNull(String key) {
-      appendFieldUnescaped(key, "null");
-      return this;
-    }
-
-    /**
-     * Appends a string field to the JSON.
-     *
-     * @param key The key of the field.
-     * @param value The value of the field.
-     * @return A reference to this object.
-     */
-    public JsonObjectBuilder appendField(String key, String value) {
-      if (value == null) {
-        throw new IllegalArgumentException("JSON value must not be null");
-      }
-      appendFieldUnescaped(key, "\"" + escape(value) + "\"");
-      return this;
-    }
-
-    /**
-     * Appends an integer field to the JSON.
-     *
-     * @param key The key of the field.
-     * @param value The value of the field.
-     * @return A reference to this object.
-     */
-    public JsonObjectBuilder appendField(String key, int value) {
-      appendFieldUnescaped(key, String.valueOf(value));
-      return this;
-    }
-
-    /**
-     * Appends an object to the JSON.
-     *
-     * @param key The key of the field.
-     * @param object The object.
-     * @return A reference to this object.
-     */
-    public JsonObjectBuilder appendField(String key, JsonObject object) {
-      if (object == null) {
-        throw new IllegalArgumentException("JSON object must not be null");
-      }
-      appendFieldUnescaped(key, object.toString());
-      return this;
-    }
-
-    /**
-     * Appends a string array to the JSON.
-     *
-     * @param key The key of the field.
-     * @param values The string array.
-     * @return A reference to this object.
-     */
-    public JsonObjectBuilder appendField(String key, String[] values) {
-      if (values == null) {
-        throw new IllegalArgumentException("JSON values must not be null");
-      }
-      String escapedValues =
-          Arrays.stream(values)
-              .map(value -> "\"" + escape(value) + "\"")
-              .collect(Collectors.joining(","));
-      appendFieldUnescaped(key, "[" + escapedValues + "]");
-      return this;
-    }
-
-    /**
-     * Appends an integer array to the JSON.
-     *
-     * @param key The key of the field.
-     * @param values The integer array.
-     * @return A reference to this object.
-     */
-    public JsonObjectBuilder appendField(String key, int[] values) {
-      if (values == null) {
-        throw new IllegalArgumentException("JSON values must not be null");
-      }
-      String escapedValues =
-          Arrays.stream(values).mapToObj(String::valueOf).collect(Collectors.joining(","));
-      appendFieldUnescaped(key, "[" + escapedValues + "]");
-      return this;
-    }
-
-    /**
-     * Appends an object array to the JSON.
-     *
-     * @param key The key of the field.
-     * @param values The integer array.
-     * @return A reference to this object.
-     */
-    public JsonObjectBuilder appendField(String key, JsonObject[] values) {
-      if (values == null) {
-        throw new IllegalArgumentException("JSON values must not be null");
-      }
-      String escapedValues =
-          Arrays.stream(values).map(JsonObject::toString).collect(Collectors.joining(","));
-      appendFieldUnescaped(key, "[" + escapedValues + "]");
-      return this;
-    }
-
-    /**
-     * Appends a field to the object.
-     *
-     * @param key The key of the field.
-     * @param escapedValue The escaped value of the field.
-     */
-    private void appendFieldUnescaped(String key, String escapedValue) {
-      if (builder == null) {
-        throw new IllegalStateException("JSON has already been built");
-      }
-      if (key == null) {
-        throw new IllegalArgumentException("JSON key must not be null");
-      }
-      if (hasAtLeastOneField) {
-        builder.append(",");
-      }
-      builder.append("\"").append(escape(key)).append("\":").append(escapedValue);
-      hasAtLeastOneField = true;
-    }
-
-    /**
-     * Builds the JSON string and invalidates this builder.
-     *
-     * @return The built JSON string.
-     */
-    public JsonObject build() {
-      if (builder == null) {
-        throw new IllegalStateException("JSON has already been built");
-      }
-      JsonObject object = new JsonObject(builder.append("}").toString());
-      builder = null;
-      return object;
-    }
-
-    /**
-     * Escapes the given string like stated in https://www.ietf.org/rfc/rfc4627.txt.
-     *
-     * <p>This method escapes only the necessary characters '"', '\'. and '\u0000' - '\u001F'.
-     * Compact escapes are not used (e.g., '\n' is escaped as "\u000a" and not as "\n").
-     *
-     * @param value The value to escape.
-     * @return The escaped value.
-     */
-    private static String escape(String value) {
-      final StringBuilder builder = new StringBuilder();
-      for (int i = 0; i < value.length(); i++) {
-        char c = value.charAt(i);
-        if (c == '"') {
-          builder.append("\\\"");
-        } else if (c == '\\') {
-          builder.append("\\\\");
-        } else if (c <= '\u000F') {
-          builder.append("\\u000").append(Integer.toHexString(c));
-        } else if (c <= '\u001F') {
-          builder.append("\\u00").append(Integer.toHexString(c));
-        } else {
-          builder.append(c);
-        }
-      }
-      return builder.toString();
-    }
-
-    /**
-     * A super simple representation of a JSON object.
-     *
-     * <p>This class only exists to make methods of the {@link JsonObjectBuilder} type-safe and not
-     * allow a raw string inputs for methods like {@link JsonObjectBuilder#appendField(String,
-     * JsonObject)}.
-     */
-    public static class JsonObject {
-
-      private final String value;
-
-      private JsonObject(String value) {
-        this.value = value;
-      }
-
-      @Override
-      public String toString() {
-        return value;
-      }
-    }
-  }
-}

item-nbt-api/src/main/java/de/tr7zw/changeme/nbtapi/utils/MinecraftVersion.java

@@ -2,13 +2,20 @@ package de.tr7zw.changeme.nbtapi.utils;
 
 import java.util.HashMap;
 import java.util.Map;
+import java.util.Map.Entry;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
+import org.bstats.bukkit.Metrics;
+import org.bstats.charts.DrilldownPie;
+import org.bstats.charts.SimplePie;
 import org.bukkit.Bukkit;
 import org.bukkit.plugin.Plugin;
 import org.bukkit.plugin.java.JavaPlugin;
 
+import de.tr7zw.changeme.nbtapi.utils.nmsmappings.ClassWrapper;
+import de.tr7zw.changeme.nbtapi.utils.nmsmappings.ReflectionMethod;
+
 /**
  * This class acts as the "Brain" of the NBTApi. It contains the main logger for
  * other classes,registers bStats and checks rather Maven shading was done
@@ -24,11 +31,15 @@ public enum MinecraftVersion {
     MC1_13_R1(1131), MC1_13_R2(1132), MC1_14_R1(1141), MC1_15_R1(1151), MC1_16_R1(1161), MC1_16_R2(1162),
     MC1_16_R3(1163), MC1_17_R1(1171), MC1_18_R1(1181, true), MC1_18_R2(1182, true), MC1_19_R1(1191, true),
     MC1_19_R2(1192, true), MC1_19_R3(1193, true), MC1_20_R1(1201, true), MC1_20_R2(1202, true), MC1_20_R3(1203, true),
-    MC1_20_R4(1204, true), MC1_21_R1(1211, true), MC1_21_R2(1212, true);
+    MC1_20_R4(1204, true), MC1_21_R1(1211, true), MC1_21_R2(1212, true), MC1_21_R3(1213, true), MC1_21_R4(1214, true), 
+    MC1_21_R5(1215, true), MC1_21_R6(1216, true), MC1_21_R7(1217, true), MC26_1(260100, true), MC26_2(260200, true),
+    MC26_3(260300, true);
 
     private static MinecraftVersion version;
     private static Boolean hasGsonSupport;
     private static Boolean isForgePresent;
+    private static Boolean isNeoForgePresent;
+    private static Boolean isFabricPresent;
     private static Boolean isFoliaPresent;
     private static boolean bStatsDisabled = false;
     private static boolean disablePackageWarning = false;
@@ -39,13 +50,12 @@ public enum MinecraftVersion {
     private static Logger logger = Logger.getLogger("NBTAPI");
 
     // NBT-API Version
-    protected static final String VERSION = "2.14.0";
+    protected static final String VERSION = "2.16.1";
 
     private final int versionId;
     private final boolean mojangMapping;
 
     // TODO: not nice
-    @SuppressWarnings("serial")
     private static final Map<String, MinecraftVersion> VERSION_TO_REVISION = new HashMap<String, MinecraftVersion>() {
         { 
             this.put("1.20", MC1_20_R1);
@@ -59,6 +69,17 @@ public enum MinecraftVersion {
             this.put("1.21.1", MC1_21_R1);
             this.put("1.21.2", MC1_21_R2);
             this.put("1.21.3", MC1_21_R2);
+            this.put("1.21.4", MC1_21_R3);
+            this.put("1.21.5", MC1_21_R4);
+            this.put("1.21.6", MC1_21_R5);
+            this.put("1.21.7", MC1_21_R5);
+            this.put("1.21.8", MC1_21_R5);
+            this.put("1.21.9", MC1_21_R6);
+            this.put("1.21.10", MC1_21_R6);
+            this.put("1.21.11", MC1_21_R7);
+            this.put("26.1", MC26_1);
+            this.put("26.2", MC26_2);
+            this.put("26.3", MC26_3);
         }
     };
 
@@ -140,8 +161,22 @@ public enum MinecraftVersion {
         } catch (Exception ex) {
             logger.info("[NBTAPI] Found Minecraft: " + Bukkit.getServer().getBukkitVersion().split("-")[0]
                     + "! Trying to find NMS support");
-            version = VERSION_TO_REVISION.getOrDefault(Bukkit.getServer().getBukkitVersion().split("-")[0],
-                    MinecraftVersion.UNKNOWN);
+            version = VERSION_TO_REVISION.get(Bukkit.getServer().getBukkitVersion().split("-")[0]);
+            if (version == null) {
+                // check for modern versions with the new versioning scheme, also the new paper version format
+                String versionString = Bukkit.getServer().getBukkitVersion().split("-")[0].split(".build")[0];
+                for (Entry<String, MinecraftVersion> entry : VERSION_TO_REVISION.entrySet()) {
+                    if (versionString.startsWith(entry.getKey()) && version == null) {
+                        version = entry.getValue();
+                        // pick the highest revision that matches the version string, in case 26.1.3 is somehow different to 26.1
+                    } else if (versionString.startsWith(entry.getKey()) && entry.getValue().getVersionId() > version.getVersionId()) {
+                        version = entry.getValue();
+                    }
+                }
+            }
+            if (version == null) {
+                version = UNKNOWN;
+            }
         }
         if (version != UNKNOWN) {
             logger.info("[NBTAPI] NMS support '" + version.name() + "' loaded!");
@@ -160,13 +195,70 @@ public enum MinecraftVersion {
     }
 
     private static void init() {
+        // Maven's Relocate is clever and changes strings, too. So we have to use this
+        // little "trick" ... :D (from bStats)
+        final String defaultPackage = new String(new byte[] { 'd', 'e', '.', 't', 'r', '7', 'z', 'w', '.', 'c', 'h',
+                'a', 'n', 'g', 'e', 'm', 'e', '.', 'n', 'b', 't', 'a', 'p', 'i', '.', 'u', 't', 'i', 'l', 's' });
+        final String reservedPackage = new String(new byte[] { 'd', 'e', '.', 't', 'r', '7', 'z', 'w', '.', 'n', 'b',
+                't', 'a', 'p', 'i', '.', 'u', 't', 'i', 'l', 's' });
         try {
             if (hasGsonSupport() && !bStatsDisabled) {
                 Plugin plugin = Bukkit.getPluginManager().getPlugin(VersionChecker.getPlugin());
                 if (plugin != null && plugin instanceof JavaPlugin) {
                     getLogger()
                             .info("[NBTAPI] Using the plugin '" + plugin.getName() + "' to create a bStats instance!");
-                    new Metrics((JavaPlugin) plugin, 1058);
+                    Metrics metrics = new Metrics((JavaPlugin) plugin, 1058);
+                    metrics.addCustomChart(new SimplePie("nbtapi_version", () -> {
+                        return VERSION;
+                    }));
+                    metrics.addCustomChart(new DrilldownPie("nms_version", () -> {
+                        Map<String, Map<String, Integer>> map = new HashMap<>();
+                        Map<String, Integer> entry = new HashMap<>();
+                        entry.put(Bukkit.getName(), 1);
+                        map.put(getVersion().name(), entry);
+                        return map;
+                    }));
+                    metrics.addCustomChart(new SimplePie("shaded", () -> {
+                        return Boolean.toString(!"NBTAPI".equals(VersionChecker.getPlugin()));
+                    }));
+                    metrics.addCustomChart(new SimplePie("server_software", () -> {
+                        return Bukkit.getName();
+                    }));
+                    metrics.addCustomChart(new SimplePie("parent_plugin", () -> {
+                        return VersionChecker.getPluginforBStats();
+                    }));
+                    metrics.addCustomChart(new SimplePie("parent_plugin_type", () -> {
+                        return VersionChecker.getPluginType();
+                    }));
+                    metrics.addCustomChart(new SimplePie("special_environment", () -> {
+                        if (isFoliaPresent()) {
+                            return "Folia";
+                        } else if (isForgePresent()) {
+                            return "Forge";
+                        } else if (isFabricPresent()) {
+                            return "Fabric";
+                        } else if (isNeoForgePresent()) {
+                            return "NeoForge";
+                        } else {
+                            return "None";
+                        }
+                    }));
+                    metrics.addCustomChart(new SimplePie("bindings_check", () -> {
+                        
+                        boolean failedBinding = false;
+                        for (ClassWrapper c : ClassWrapper.values()) {
+                            if (c.isEnabled() && c.getClazz() == null) {
+                                failedBinding = true;
+                            }
+                        }
+                        for (ReflectionMethod method : ReflectionMethod.values()) {
+                            if (method.isCompatible() && !method.isLoaded()) {
+                                failedBinding = true;
+                            }
+                        }
+                        
+                        return failedBinding ? "Failed" : "Pass";
+                    }));
                 } else if (plugin == null) {
                     getLogger().info("[NBTAPI] Unable to create a bStats instance!!");
                 }
@@ -183,12 +275,6 @@ public enum MinecraftVersion {
                     logger.log(Level.WARNING, "[NBTAPI] Error while checking for updates! Error: " + ex.getMessage());
                 }
             }).start();
-        // Maven's Relocate is clever and changes strings, too. So we have to use this
-        // little "trick" ... :D (from bStats)
-        final String defaultPackage = new String(new byte[] { 'd', 'e', '.', 't', 'r', '7', 'z', 'w', '.', 'c', 'h',
-                'a', 'n', 'g', 'e', 'm', 'e', '.', 'n', 'b', 't', 'a', 'p', 'i', '.', 'u', 't', 'i', 'l', 's' });
-        final String reservedPackage = new String(new byte[] { 'd', 'e', '.', 't', 'r', '7', 'z', 'w', '.', 'n', 'b',
-                't', 'a', 'p', 'i', '.', 'u', 't', 'i', 'l', 's' });
         if (!disablePackageWarning && MinecraftVersion.class.getPackage().getName().equals(defaultPackage)) {
             logger.warning(
                     "#########################################- NBTAPI -#########################################");
@@ -248,6 +334,22 @@ public enum MinecraftVersion {
         return hasGsonSupport;
     }
 
+    /**
+     * @return True, if Fabric is present
+     */
+    public static boolean isFabricPresent() {
+        if (isFabricPresent != null) {
+            return isFabricPresent;
+        }
+        try {
+            logger.info("[NBTAPI] Found Fabric: " + Class.forName("net.fabricmc.api.ModInitializer"));
+            isFabricPresent = true;
+        } catch (Exception ex) {
+            isFabricPresent = false;
+        }
+        return isFabricPresent;
+    }
+    
     /**
      * @return True, if Forge is present
      */
@@ -265,6 +367,22 @@ public enum MinecraftVersion {
         }
         return isForgePresent;
     }
+    
+    /**
+     * @return True, if NeoForge is present
+     */
+    public static boolean isNeoForgePresent() {
+        if (isNeoForgePresent != null) {
+            return isNeoForgePresent;
+        }
+        try {
+            logger.info("[NBTAPI] Found NeoForge: " + Class.forName("net.neoforged.neoforge.common.NeoForge"));
+            isNeoForgePresent = true;
+        } catch (Exception ex) {
+            isNeoForgePresent = false;
+        }
+        return isNeoForgePresent;
+    }
 
     /**
      * @return True, if Folia is present

item-nbt-api/src/main/java/de/tr7zw/changeme/nbtapi/utils/NBTJsonUtil.java

@@ -0,0 +1,41 @@
+package de.tr7zw.changeme.nbtapi.utils;
+
+import java.util.Optional;
+
+import org.bukkit.inventory.ItemStack;
+
+import com.google.gson.JsonElement;
+import com.mojang.serialization.Codec;
+import com.mojang.serialization.DataResult;
+import com.mojang.serialization.JsonOps;
+
+import de.tr7zw.changeme.nbtapi.NbtApiException;
+import de.tr7zw.changeme.nbtapi.utils.nmsmappings.ClassWrapper;
+import de.tr7zw.changeme.nbtapi.utils.nmsmappings.MojangToMapping;
+import de.tr7zw.changeme.nbtapi.utils.nmsmappings.ReflectionMethod;
+
+public class NBTJsonUtil {
+
+    /**
+     * 1.20.3-1.21.4 only. Used to convert items into Json, used in Chat Hover Components.
+     * 
+     * @param itemStack
+     * @return
+     * @throws NbtApiException
+     */
+    @SuppressWarnings("unchecked")
+    public static JsonElement itemStackToJson(ItemStack itemStack) {
+        try {
+            Codec<Object> itemStackCodec = (Codec<Object>) ClassWrapper.NMS_ITEMSTACK.getClazz()
+                    .getField(MojangToMapping.getMapping().get("net.minecraft.world.item.ItemStack#CODEC")).get(null);
+            Object stack = ReflectionMethod.ITEMSTACK_NMSCOPY.run(null, itemStack);
+            DataResult<JsonElement> result = itemStackCodec.encode(stack, JsonOps.INSTANCE,
+                    JsonOps.INSTANCE.emptyMap());
+            Optional<JsonElement> opt = (Optional<JsonElement>) result.getClass().getMethod("result").invoke(result);
+            return opt.orElse(null);
+        } catch (Exception ex) {
+            throw new NbtApiException("Error trying to get Json of an ItemStack.", ex);
+        }
+    }
+
+}

item-nbt-api/src/main/java/de/tr7zw/changeme/nbtapi/utils/ReflectionUtil.java

@@ -1,53 +1,24 @@
 package de.tr7zw.changeme.nbtapi.utils;
 
 import java.lang.reflect.Field;
-import java.lang.reflect.Method;
-import java.lang.reflect.Modifier;
 
 import de.tr7zw.changeme.nbtapi.NbtApiException;
+import de.tr7zw.changeme.nbtapi.utils.nmsmappings.MojangToMapping;
 
 public final class ReflectionUtil {
-
-    private static Field field_modifiers;
-
-    static {
+    
+    public static Field getMappedField(Class<?> clazz, String mapping) {
+        String mojmapName = mapping.split("#")[1];
         try {
-            field_modifiers = Field.class.getDeclaredField("modifiers");
-            field_modifiers.setAccessible(true);
-        } catch (NoSuchFieldException ex) {
-            try {
-                // This hacky workaround is for newer jdk versions 11+?
-                Method fieldGetter = Class.class.getDeclaredMethod("getDeclaredFields0", boolean.class);
-                fieldGetter.setAccessible(true);
-                Field[] fields = (Field[]) fieldGetter.invoke(Field.class, false);
-                for (Field f : fields)
-                    if (f.getName().equals("modifiers")) {
-                        field_modifiers = f;
-                        field_modifiers.setAccessible(true);
-                        break;
-                    }
-            } catch (Exception e) {
-                throw new NbtApiException(e);
-            }
+            return clazz.getField(mojmapName);
+        } catch (NoSuchFieldException | SecurityException e) {
+            // not Mojamp, try remapped
         }
-        if (field_modifiers == null) {
-            throw new NbtApiException("Unable to init the modifiers Field.");
+        try {
+            return clazz.getDeclaredField(MojangToMapping.getMapping().get(mapping));
+        } catch (Exception e) {
+            throw new NbtApiException("Unable to find field " + mapping + " in class " + clazz.getName(), e);
         }
     }
 
-    public static Field makeNonFinal(Field field) throws IllegalArgumentException, IllegalAccessException {
-        int mods = field.getModifiers();
-        if (Modifier.isFinal(mods)) {
-            field_modifiers.set(field, mods & ~Modifier.FINAL);
-        }
-        return field;
-    }
-
-    public static void setFinal(Object obj, Field field, Object newValue)
-            throws IllegalArgumentException, IllegalAccessException {
-        field.setAccessible(true);
-        field = makeNonFinal(field);
-        field.set(obj, newValue);
-    }
-
 }

item-nbt-api/src/main/java/de/tr7zw/changeme/nbtapi/utils/VersionChecker.java

@@ -109,7 +109,20 @@ public class VersionChecker {
 
     protected static String getPlugin() {
         ClassLoader classLoader = VersionChecker.class.getClassLoader();
-        InputStream inputStream = classLoader.getResourceAsStream("plugin.yml");
+        InputStream inputStream = classLoader.getResourceAsStream("paper-plugin.yml");
+        if (inputStream != null) {
+            try (InputStreamReader reader = new InputStreamReader(inputStream)) {
+                YamlConfiguration pluginYml = YamlConfiguration.loadConfiguration(reader);
+                return pluginYml.getString("name");
+            } catch (IOException e) {
+                // ignored
+            } catch (IllegalArgumentException e) {
+                // This can happen if the paper-plugin.yml is not formatted correctly
+                MinecraftVersion.getLogger().log(Level.WARNING, "[NBTAPI] Error reading paper-plugin.yml: " + e.getMessage());
+            }
+        }
+        
+        inputStream = classLoader.getResourceAsStream("plugin.yml");
 
         if (inputStream != null) {
             try (InputStreamReader reader = new InputStreamReader(inputStream)) {
@@ -117,9 +130,67 @@ public class VersionChecker {
                 return pluginYml.getString("name");
             } catch (IOException e) {
                 // ignored
+            } catch (IllegalArgumentException e) {
+                // This can happen if the plugin.yml is not formatted correctly
+                MinecraftVersion.getLogger().log(Level.WARNING, "[NBTAPI] Error reading plugin.yml: " + e.getMessage());
             }
         }
         return NBTItem.class.getPackage().getName();
     }
+    
+    protected static String getPluginforBStats() {
+        ClassLoader classLoader = VersionChecker.class.getClassLoader();
+        InputStream inputStream = classLoader.getResourceAsStream("paper-plugin.yml");
+        if (inputStream != null) {
+            try (InputStreamReader reader = new InputStreamReader(inputStream)) {
+                YamlConfiguration pluginYml = YamlConfiguration.loadConfiguration(reader);
+                return pluginYml.getString("name");
+            } catch (IOException e) {
+                // ignored
+            } catch (IllegalArgumentException e) {
+                // This can happen if the paper-plugin.yml is not formatted correctly
+                MinecraftVersion.getLogger().log(Level.WARNING, "[NBTAPI] Error reading paper-plugin.yml: " + e.getMessage());
+            }
+        }
+        
+        inputStream = classLoader.getResourceAsStream("plugin.yml");
+
+        if (inputStream != null) {
+            try (InputStreamReader reader = new InputStreamReader(inputStream)) {
+                YamlConfiguration pluginYml = YamlConfiguration.loadConfiguration(reader);
+                return pluginYml.getString("name");
+            } catch (IOException e) {
+                // ignored
+            } catch (IllegalArgumentException e) {
+                // This can happen if the plugin.yml is not formatted correctly
+                MinecraftVersion.getLogger().log(Level.WARNING, "[NBTAPI] Error reading plugin.yml: " + e.getMessage());
+            }
+        }
+        return "UnknownPlugin";
+    }
+    
+    protected static String getPluginType() {
+        ClassLoader classLoader = VersionChecker.class.getClassLoader();
+        InputStream inputStream = classLoader.getResourceAsStream("paper-plugin.yml");
+        if (inputStream != null) {
+            try {
+                inputStream.close();
+            } catch (IOException e) {
+                // ignored
+            }
+            return "PaperPlugin";
+        }
+        
+        inputStream = classLoader.getResourceAsStream("plugin.yml");
+        if (inputStream != null) {
+            try {
+                inputStream.close();
+            } catch (IOException e) {
+                // ignored
+            }
+            return "SpigotPlugin";
+        }
+        return "UnknownPlugin";
+    }
 
 }

item-nbt-api/src/main/java/de/tr7zw/changeme/nbtapi/utils/nmsmappings/ClassWrapper.java

@@ -24,6 +24,7 @@ public enum ClassWrapper {
     CRAFT_PERSISTENTDATACONTAINER(PackageWrapper.CRAFTBUKKIT, "persistence.CraftPersistentDataContainer",
             MinecraftVersion.MC1_14_R1, null),
     NMS_NBTBASE(PackageWrapper.NMS, "NBTBase", null, null, "net.minecraft.nbt", "net.minecraft.nbt.Tag"),
+    NMS_TAGTYPE(PackageWrapper.NMS, "NBTTagType", MinecraftVersion.MC1_21_R4, null, "net.minecraft.nbt", "net.minecraft.nbt.TagType"),
     NMS_NBTTAGSTRING(PackageWrapper.NMS, "NBTTagString", null, null, "net.minecraft.nbt",
             "net.minecraft.nbt.StringTag"),
     NMS_NBTTAGINT(PackageWrapper.NMS, "NBTTagInt", null, null, "net.minecraft.nbt", "net.minecraft.nbt.IntTag"),
@@ -85,6 +86,18 @@ public enum ClassWrapper {
             "net.minecraft.util.datafix.fixes", "net.minecraft.util.datafix.fixes.References"),
     NMS_NBTOPS(PackageWrapper.NMS, "DynamicOpsNBT", MinecraftVersion.MC1_20_R4, null,
             "net.minecraft.nbt", "net.minecraft.nbt.NbtOps"),
+    NMS_PROBLEM_REPORTER(PackageWrapper.NMS, "ProblemReporter", MinecraftVersion.MC1_21_R5, null,
+            "net.minecraft.util", "net.minecraft.util.ProblemReporter"),
+    NMS_TAG_VALUE_INPUT(PackageWrapper.NMS, "TagValueInput", MinecraftVersion.MC1_21_R5, null,
+            "net.minecraft.world.level.storage", "net.minecraft.world.level.storage.TagValueInput"),
+    NMS_VALUE_INPUT(PackageWrapper.NMS, "ValueInput", MinecraftVersion.MC1_21_R5, null,
+            "net.minecraft.world.level.storage", "net.minecraft.world.level.storage.ValueInput"),
+    NMS_TAG_VALUE_OUTPUT(PackageWrapper.NMS, "TagValueOutput", MinecraftVersion.MC1_21_R5, null,
+            "net.minecraft.world.level.storage", "net.minecraft.world.level.storage.TagValueOutput"),
+    NMS_VALUE_OUTPUT(PackageWrapper.NMS, "ValueOutput", MinecraftVersion.MC1_21_R5, null,
+            "net.minecraft.world.level.storage", "net.minecraft.world.level.storage.ValueOutput"),
+    NMS_DYNAMICOPS(PackageWrapper.NONE, "DynamicOps", MinecraftVersion.MC1_21_R5, null,
+            "com.mojang.serialization", "com.mojang.serialization.DynamicOps"),
     GAMEPROFILE(PackageWrapper.NONE, "com.mojang.authlib.GameProfile", MinecraftVersion.MC1_8_R3, null);
 
     private Class<?> clazz;

item-nbt-api/src/main/java/de/tr7zw/changeme/nbtapi/utils/nmsmappings/CodecHelper.java

@@ -0,0 +1,35 @@
+package de.tr7zw.changeme.nbtapi.utils.nmsmappings;
+
+import java.util.Objects;
+import java.util.Optional;
+
+import de.tr7zw.changeme.nbtapi.NBTReflectionUtil;
+import de.tr7zw.changeme.nbtapi.NbtApiException;
+
+public class CodecHelper {
+
+    public static Object convertItemStackToNbt(Object itemStack) {
+        Object result = null;
+        try {
+            // FIXME caching, this has 0 exception handling
+            result = NBTReflectionUtil.itemstack_codec.encodeStart(NBTReflectionUtil.nbtRegistryOps, itemStack);
+            Objects.requireNonNull(result);
+            return ((Optional<Object>)result.getClass().getMethod("result").invoke(result)).get();
+        } catch (Exception e) {
+            throw new NbtApiException("Failed to convert ItemStack to NBT. " + result + " " + itemStack, e);
+        }
+    }
+    
+    public static Object convertNbtToItemStack(Object nbt) {
+        Object result = null;
+        try {
+            // FIXME caching, this has 0 exception handling
+            result = NBTReflectionUtil.itemstack_codec.parse(NBTReflectionUtil.nbtRegistryOps, nbt);
+            Objects.requireNonNull(result);
+            return ((Optional<Object>)result.getClass().getMethod("result").invoke(result)).get();
+        } catch (Exception e) {
+            throw new NbtApiException("Failed to convert NBT to ItemStack. " + result + " " + nbt, e);
+        }
+    }
+    
+}

item-nbt-api/src/main/java/de/tr7zw/changeme/nbtapi/utils/nmsmappings/Forge1710Mappings.java

@@ -56,8 +56,8 @@ public class Forge1710Mappings {
         methodMap.put("COMPOUND_MERGE", "merge");// Only present on Crucible
         methodMap.put("COMPOUND_SET", "func_74782_a");
         methodMap.put("COMPOUND_GET", "func_74781_a");
-        methodMap.put("COMPOUND_GET_LIST", "func_150295_c");
-        methodMap.put("COMPOUND_OWN_TYPE", "func_74732_a");
+        methodMap.put("COMPOUND_GET_LIST_LEGACY", "func_150295_c");
+        methodMap.put("COMPOUND_OWN_TYPE_LEGACY", "func_74732_a");
         methodMap.put("COMPOUND_GET_FLOAT", "func_74760_g");
         methodMap.put("COMPOUND_GET_STRING", "func_74779_i");
         methodMap.put("COMPOUND_GET_INT", "func_74762_e");

item-nbt-api/src/main/java/de/tr7zw/changeme/nbtapi/utils/nmsmappings/MojangToMapping.java

@@ -1,5 +1,6 @@
 package de.tr7zw.changeme.nbtapi.utils.nmsmappings;
 
+import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
 
@@ -145,6 +146,7 @@ public class MojangToMapping {
             put("net.minecraft.world.entity.Entity#getEncodeId()", "bw");
             put("net.minecraft.world.level.block.entity.BlockEntity#saveWithId()", "p");
             put("net.minecraft.world.level.block.entity.BlockEntity#getBlockState()", "r");
+            put("net.minecraft.world.item.ItemStack#CODEC", "a");
         }
 
     };
@@ -169,6 +171,7 @@ public class MojangToMapping {
             put("net.minecraft.util.datafix.DataFixers#getDataFixer()", "a");
             put("net.minecraft.util.datafix.fixes.References#ITEM_STACK", "t");
             put("net.minecraft.nbt.NbtOps#INSTANCE", "a");
+            put("net.minecraft.world.item.ItemStack#CODEC", "b");
         }
 
     };
@@ -193,14 +196,144 @@ public class MojangToMapping {
             put("net.minecraft.server.MinecraftServer#registryAccess()", "ba");
             put("net.minecraft.world.entity.Entity#getEncodeId()", "bK");
             put("net.minecraft.world.level.block.entity.BlockEntity#getBlockState()", "m");
+            put("net.minecraft.world.item.ItemStack#CODEC", "a");
+        }
+
+    };
+
+    @SuppressWarnings("serial")
+    private static Map<String, String> MC1_21R3 = new HashMap<String, String>() {
+
+        {
+            putAll(MC1_21R2);
+
+            put("net.minecraft.world.item.component.CustomData#copyTag()", "d");
+        }
+
+    };
+    
+    @SuppressWarnings("serial")
+    private static Map<String, String> MC1_21R4 = new HashMap<String, String>() {
+
+        {
+            putAll(MC1_21R3);
+
+            put("net.minecraft.nbt.CompoundTag#getShort(java.lang.String)", "d");
+            put("net.minecraft.nbt.CompoundTag#getString(java.lang.String)", "i");
+            put("net.minecraft.nbt.CompoundTag#contains(java.lang.String)", "b");
+            put("net.minecraft.nbt.CompoundTag#getDouble(java.lang.String)", "h");
+            put("net.minecraft.nbt.CompoundTag#getByteArray(java.lang.String)", "j");
+            put("net.minecraft.nbt.CompoundTag#getFloat(java.lang.String)", "g");
+            put("net.minecraft.nbt.CompoundTag#get(java.lang.String)", "a");
+            put("net.minecraft.nbt.CompoundTag#getLong(java.lang.String)", "f");
+            put("net.minecraft.nbt.CompoundTag#getLongArray(java.lang.String)", "l");
+            put("net.minecraft.nbt.CompoundTag#getInt(java.lang.String)", "e");
+            put("net.minecraft.nbt.CompoundTag#getIntArray(java.lang.String)", "k");
+            put("net.minecraft.nbt.CompoundTag#getCompound(java.lang.String)", "m");
+            put("net.minecraft.nbt.CompoundTag#getByte(java.lang.String)", "c");
+            put("net.minecraft.nbt.ListTag#getString(int)", "m");
+            put("net.minecraft.world.entity.Entity#saveWithoutId(net.minecraft.nbt.CompoundTag)", "h");
+            put("net.minecraft.world.entity.Entity#getEncodeId()", "bI");
+            put("net.minecraft.world.entity.Entity#load(net.minecraft.nbt.CompoundTag)", "i");
+            put("net.minecraft.nbt.Tag#getType()", "c");
+            put("net.minecraft.nbt.TagType#getName()", "a");
+            put("net.minecraft.nbt.CompoundTag#getList(java.lang.String)", "o");
+            put("net.minecraft.world.item.ItemStack#parse(net.minecraft.core.HolderLookup$Provider,net.minecraft.nbt.Tag)", "a");
+            put("net.minecraft.world.item.ItemStack#CODEC", "b");
+        }
+
+    };
+    
+    @SuppressWarnings("serial")
+    private static Map<String, String> MC1_21R5 = new HashMap<String, String>() {
+
+        {
+            putAll(MC1_21R3);
+            put("net.minecraft.core.HolderLookup$Provider#createSerializationContext(com.mojang.serialization.DynamicOps)", "a");
+            put("net.minecraft.nbt.CompoundTag#getByteArray(java.lang.String)", "j");
+            put("net.minecraft.nbt.CompoundTag#getDouble(java.lang.String)", "h");
+            put("net.minecraft.nbt.CompoundTag#keySet()", "e");
+            put("net.minecraft.nbt.CompoundTag#getLong(java.lang.String)", "f");
+            put("net.minecraft.nbt.CompoundTag#getList(java.lang.String)", "o");
+            put("net.minecraft.nbt.CompoundTag#getInt(java.lang.String)", "e");
+            put("net.minecraft.nbt.CompoundTag#getCompound(java.lang.String)", "m");
+            put("net.minecraft.nbt.CompoundTag#getByte(java.lang.String)", "c");
+            put("net.minecraft.nbt.CompoundTag#getShort(java.lang.String)", "d");
+            put("net.minecraft.nbt.CompoundTag#getIntArray(java.lang.String)", "k");
+            put("net.minecraft.nbt.CompoundTag#get(java.lang.String)", "a");
+            put("net.minecraft.nbt.CompoundTag#getString(java.lang.String)", "i");
+            put("net.minecraft.nbt.CompoundTag#getFloat(java.lang.String)", "g");
+            put("net.minecraft.nbt.CompoundTag#getLongArray(java.lang.String)", "l");
+            put("net.minecraft.nbt.CompoundTag#contains(java.lang.String)", "b");
+            put("net.minecraft.nbt.ListTag#getString(int)", "m");
+            put("net.minecraft.nbt.Tag#getType()", "c");
+            put("net.minecraft.nbt.TagParser#parseCompoundFully(java.lang.String)", "a");
+            put("net.minecraft.nbt.TagType#getName()", "a");
+            put("net.minecraft.world.entity.Entity#load(net.minecraft.world.level.storage.ValueInput)", "e");
+            put("net.minecraft.world.entity.Entity#getEncodeId()", "bN");
+            put("net.minecraft.world.entity.Entity#saveWithoutId(net.minecraft.world.level.storage.ValueOutput)", "d");
+            put("net.minecraft.world.level.block.entity.BlockEntity#saveWithId(net.minecraft.world.level.storage.ValueOutput)", "d");
+            put("net.minecraft.world.level.block.entity.BlockEntity#loadWithComponents(net.minecraft.world.level.storage.ValueInput)", "b");
+            put("net.minecraft.world.level.storage.TagValueInput#create(net.minecraft.util.ProblemReporter,net.minecraft.core.HolderLookup$Provider,net.minecraft.nbt.CompoundTag)", "a");
+            put("net.minecraft.world.level.storage.TagValueOutput#createWithContext(net.minecraft.util.ProblemReporter,net.minecraft.core.HolderLookup$Provider)", "a");
+            put("net.minecraft.world.level.storage.TagValueOutput#buildResult()", "b");
+            put("net.minecraft.world.item.ItemStack#CODEC", "b");
+            put("net.minecraft.util.ProblemReporter#DISCARDING", "a");
+            put("net.minecraft.util.datafix.fixes.References#ITEM_STACK", "u");
+
+        }
+
+    };
+    
+    @SuppressWarnings("serial")
+    private static Map<String, String> MC1_21R6 = new HashMap<String, String>() {
+
+        {
+            putAll(MC1_21R5);
+
+            put("net.minecraft.server.MinecraftServer#registryAccess()", "bg");
+            put("net.minecraft.world.entity.Entity#load(net.minecraft.world.level.storage.ValueInput)", "d");
+            put("net.minecraft.world.entity.Entity#getEncodeId()", "bW");
+            put("net.minecraft.world.item.component.CustomData#copyTag()", "b");
+            put("net.minecraft.world.level.block.entity.BlockEntity#getBlockState()", "o");
+            put("net.minecraft.util.datafix.fixes.References#ITEM_STACK", "v");
+
+        }
+
+    };
+    
+    @SuppressWarnings("serial")
+    private static Map<String, String> MC1_21R7 = new HashMap<String, String>() {
+
+        {
+            putAll(MC1_21R6);
+
+            put("net.minecraft.nbt.NbtAccounter#unlimitedHeap()", "c");
+            put("net.minecraft.server.MinecraftServer#registryAccess()", "bc");
+            put("net.minecraft.world.entity.Entity#getEncodeId()", "ca");
+            put("net.minecraft.util.datafix.fixes.References#ITEM_STACK", "x");
+
         }
 
     };
 
 
-
     public static Map<String, String> getMapping() {
+        // No mappings after 26.1
+        if(MinecraftVersion.getVersion() != MinecraftVersion.UNKNOWN && MinecraftVersion.getVersion().isAtLeastVersion(MinecraftVersion.MC26_1)) {
+            return Collections.EMPTY_MAP;
+        }
         switch (MinecraftVersion.getVersion()) {
+        case MC1_21_R7:
+            return MC1_21R7;
+        case MC1_21_R6:
+            return MC1_21R6;
+        case MC1_21_R5:
+            return MC1_21R5;
+        case MC1_21_R4:
+            return MC1_21R4;
+        case MC1_21_R3:
+            return MC1_21R3;
         case MC1_21_R2:
             return MC1_21R2;
         case MC1_21_R1:
@@ -224,7 +357,7 @@ public class MojangToMapping {
         case MC1_18_R1:
             return MC1_18R1;
         case UNKNOWN:
-            return MC1_20R2; // assume it's a future version, so try the latest known mappings
+            return MC1_21R7; // assume it's a future version, so try the latest known mappings
         default:
             // this should never happen, unless a version is forgotten here(like 1.19R3 which uses the 1.19R2 mappings)
             throw new NbtApiException("No fitting mapping found for version " + MinecraftVersion.getVersion() + ". This is a bug!");

item-nbt-api/src/main/java/de/tr7zw/changeme/nbtapi/utils/nmsmappings/ReflectionMethod.java

@@ -5,6 +5,8 @@ import java.io.OutputStream;
 import java.lang.reflect.Method;
 import java.util.Arrays;
 import java.util.UUID;
+import java.util.stream.Collectors;
+
 import org.bukkit.inventory.ItemStack;
 
 import de.tr7zw.changeme.nbtapi.NbtApiException;
@@ -54,7 +56,7 @@ public enum ReflectionMethod {
             MinecraftVersion.MC1_7_R4, new Since(MinecraftVersion.MC1_7_R4, "setBoolean"),
             new Since(MinecraftVersion.MC1_18_R1, "putBoolean(java.lang.String,boolean)")),
     COMPOUND_SET_UUID(ClassWrapper.NMS_NBTTAGCOMPOUND, new Class[] { String.class, UUID.class },
-            MinecraftVersion.MC1_16_R1, new Since(MinecraftVersion.MC1_16_R1, "a"),
+            MinecraftVersion.MC1_16_R1, MinecraftVersion.MC1_21_R3, new Since(MinecraftVersion.MC1_16_R1, "a"),
             new Since(MinecraftVersion.MC1_18_R1, "putUUID(java.lang.String,java.util.UUID)")),
     COMPOUND_MERGE(ClassWrapper.NMS_NBTTAGCOMPOUND, new Class[] { ClassWrapper.NMS_NBTTAGCOMPOUND.getClazz() },
             MinecraftVersion.MC1_8_R3, new Since(MinecraftVersion.MC1_8_R3, "a"),
@@ -65,12 +67,18 @@ public enum ReflectionMethod {
     COMPOUND_GET(ClassWrapper.NMS_NBTTAGCOMPOUND, new Class[] { String.class }, MinecraftVersion.MC1_7_R4,
             new Since(MinecraftVersion.MC1_7_R4, "get"),
             new Since(MinecraftVersion.MC1_18_R1, "get(java.lang.String)")),
-    COMPOUND_GET_LIST(ClassWrapper.NMS_NBTTAGCOMPOUND, new Class[] { String.class, int.class },
-            MinecraftVersion.MC1_7_R4, new Since(MinecraftVersion.MC1_7_R4, "getList"),
+    COMPOUND_GET_LIST_LEGACY(ClassWrapper.NMS_NBTTAGCOMPOUND, new Class[] { String.class, int.class },
+            MinecraftVersion.MC1_7_R4, MinecraftVersion.MC1_21_R3, new Since(MinecraftVersion.MC1_7_R4, "getList"),
             new Since(MinecraftVersion.MC1_18_R1, "getList(java.lang.String,int)")),
+    COMPOUND_GET_LIST(ClassWrapper.NMS_NBTTAGCOMPOUND, new Class[] { String.class }, MinecraftVersion.MC1_21_R4, 
+            new Since(MinecraftVersion.MC1_21_R4, "getList(java.lang.String)")),
     // Only needed for 1.7.10 getType
-    COMPOUND_OWN_TYPE(ClassWrapper.NMS_NBTBASE, new Class[] {}, MinecraftVersion.MC1_7_R4, MinecraftVersion.MC1_7_R4,
+    COMPOUND_OWN_TYPE_LEGACY(ClassWrapper.NMS_NBTBASE, new Class[] {}, MinecraftVersion.MC1_7_R4, MinecraftVersion.MC1_7_R4,
             new Since(MinecraftVersion.MC1_7_R4, "getTypeId")),
+    TAGTYPE_OWN_TYPE(ClassWrapper.NMS_NBTBASE, new Class[] {}, MinecraftVersion.MC1_21_R4,
+            new Since(MinecraftVersion.MC1_21_R4, "getType()")),
+    TAGTYPE_GET_NAME(ClassWrapper.NMS_TAGTYPE, new Class[] {}, MinecraftVersion.MC1_21_R4,
+            new Since(MinecraftVersion.MC1_21_R4, "getName()")),
 
     COMPOUND_GET_FLOAT(ClassWrapper.NMS_NBTTAGCOMPOUND, new Class[] { String.class }, MinecraftVersion.MC1_7_R4,
             new Since(MinecraftVersion.MC1_7_R4, "getFloat"),
@@ -105,13 +113,14 @@ public enum ReflectionMethod {
     COMPOUND_GET_BOOLEAN(ClassWrapper.NMS_NBTTAGCOMPOUND, new Class[] { String.class }, MinecraftVersion.MC1_7_R4,
             new Since(MinecraftVersion.MC1_7_R4, "getBoolean"),
             new Since(MinecraftVersion.MC1_18_R1, "getBoolean(java.lang.String)")),
-    COMPOUND_GET_UUID(ClassWrapper.NMS_NBTTAGCOMPOUND, new Class[] { String.class }, MinecraftVersion.MC1_16_R1,
+    COMPOUND_GET_UUID(ClassWrapper.NMS_NBTTAGCOMPOUND, new Class[] { String.class }, MinecraftVersion.MC1_16_R1, MinecraftVersion.MC1_21_R3,
             new Since(MinecraftVersion.MC1_16_R1, "a"),
             new Since(MinecraftVersion.MC1_18_R1, "getUUID(java.lang.String)")),
     COMPOUND_GET_COMPOUND(ClassWrapper.NMS_NBTTAGCOMPOUND, new Class[] { String.class }, MinecraftVersion.MC1_7_R4,
             new Since(MinecraftVersion.MC1_7_R4, "getCompound"),
             new Since(MinecraftVersion.MC1_18_R1, "getCompound(java.lang.String)")),
-
+    
+    
     NMSITEM_GETTAG(ClassWrapper.NMS_ITEMSTACK, new Class[] {}, MinecraftVersion.MC1_7_R4, MinecraftVersion.MC1_20_R3,
             new Since(MinecraftVersion.MC1_7_R4, "getTag"), new Since(MinecraftVersion.MC1_18_R1, "getTag()")),
     NMSITEM_SAVE(ClassWrapper.NMS_ITEMSTACK, new Class[] { ClassWrapper.NMS_NBTTAGCOMPOUND.getClazz() },
@@ -126,17 +135,17 @@ public enum ReflectionMethod {
     COMPOUND_HAS_KEY(ClassWrapper.NMS_NBTTAGCOMPOUND, new Class[] { String.class }, MinecraftVersion.MC1_7_R4,
             new Since(MinecraftVersion.MC1_7_R4, "hasKey"),
             new Since(MinecraftVersion.MC1_18_R1, "contains(java.lang.String)")),
-    COMPOUND_GET_TYPE(ClassWrapper.NMS_NBTTAGCOMPOUND, new Class[] { String.class }, MinecraftVersion.MC1_8_R3,
+    COMPOUND_GET_TYPE(ClassWrapper.NMS_NBTTAGCOMPOUND, new Class[] { String.class }, MinecraftVersion.MC1_8_R3, MinecraftVersion.MC1_21_R4,
             new Since(MinecraftVersion.MC1_8_R3, "b"), new Since(MinecraftVersion.MC1_9_R1, "d"),
             new Since(MinecraftVersion.MC1_15_R1, "e"), new Since(MinecraftVersion.MC1_16_R1, "d"),
             new Since(MinecraftVersion.MC1_18_R1, "getTagType(java.lang.String)")),
     COMPOUND_GET_KEYS(ClassWrapper.NMS_NBTTAGCOMPOUND, new Class[] {}, MinecraftVersion.MC1_7_R4,
             new Since(MinecraftVersion.MC1_7_R4, "c"), new Since(MinecraftVersion.MC1_13_R1, "getKeys"),
-            new Since(MinecraftVersion.MC1_18_R1, "getAllKeys()")),
+            new Since(MinecraftVersion.MC1_18_R1, "getAllKeys()"), new Since(MinecraftVersion.MC1_21_R5, "keySet()")),
     // FIXME ?!?
-    LISTCOMPOUND_GET_KEYS(ClassWrapper.NMS_NBTTAGCOMPOUND, new Class[] {}, MinecraftVersion.MC1_7_R4,
-            new Since(MinecraftVersion.MC1_7_R4, "c"), new Since(MinecraftVersion.MC1_13_R1, "getKeys"),
-            new Since(MinecraftVersion.MC1_18_R1, "getAllKeys()")),
+//    LISTCOMPOUND_GET_KEYS(ClassWrapper.NMS_NBTTAGCOMPOUND, new Class[] {}, MinecraftVersion.MC1_7_R4,
+//            new Since(MinecraftVersion.MC1_7_R4, "c"), new Since(MinecraftVersion.MC1_13_R1, "getKeys"),
+//            new Since(MinecraftVersion.MC1_18_R1, "getAllKeys()")),
     LIST_REMOVE_KEY(ClassWrapper.NMS_NBTTAGLIST, new Class[] { int.class }, MinecraftVersion.MC1_8_R3,
             new Since(MinecraftVersion.MC1_8_R3, "a"), new Since(MinecraftVersion.MC1_9_R1, "remove"),
             new Since(MinecraftVersion.MC1_18_R1, "remove(int)")),
@@ -166,7 +175,8 @@ public enum ReflectionMethod {
     ITEMSTACK_NMSCOPY(ClassWrapper.CRAFT_ITEMSTACK, new Class[] { ItemStack.class }, MinecraftVersion.MC1_7_R4,
             new Since(MinecraftVersion.MC1_7_R4, "asNMSCopy")),
     ITEMSTACK_BUKKITMIRROR(ClassWrapper.CRAFT_ITEMSTACK, new Class[] { ClassWrapper.NMS_ITEMSTACK.getClazz() },
-            MinecraftVersion.MC1_7_R4, new Since(MinecraftVersion.MC1_7_R4, "asCraftMirror")),
+            MinecraftVersion.MC1_7_R4,
+            new Since(MinecraftVersion.MC1_7_R4, resolveItemStackBukkitMirrorMethodName())),
 
     CRAFT_WORLD_GET_HANDLE(ClassWrapper.CRAFT_WORLD, new Class[] {}, MinecraftVersion.MC1_7_R4,
             new Since(MinecraftVersion.MC1_7_R4, "getHandle")),
@@ -219,11 +229,11 @@ public enum ReflectionMethod {
     CRAFT_ENTITY_GET_HANDLE(ClassWrapper.CRAFT_ENTITY, new Class[] {}, MinecraftVersion.MC1_7_R4,
             new Since(MinecraftVersion.MC1_7_R4, "getHandle")),
     NMS_ENTITY_SET_NBT(ClassWrapper.NMS_ENTITY, new Class[] { ClassWrapper.NMS_NBTTAGCOMPOUND.getClazz() },
-            MinecraftVersion.MC1_7_R4, new Since(MinecraftVersion.MC1_7_R4, "f"),
+            MinecraftVersion.MC1_7_R4, MinecraftVersion.MC1_21_R4, new Since(MinecraftVersion.MC1_7_R4, "f"),
             new Since(MinecraftVersion.MC1_16_R1, "load"),
             new Since(MinecraftVersion.MC1_18_R1, "load(net.minecraft.nbt.CompoundTag)")),
     NMS_ENTITY_GET_NBT(ClassWrapper.NMS_ENTITY, new Class[] { ClassWrapper.NMS_NBTTAGCOMPOUND.getClazz() },
-            MinecraftVersion.MC1_7_R4, new Since(MinecraftVersion.MC1_7_R4, "e"),
+            MinecraftVersion.MC1_7_R4, MinecraftVersion.MC1_21_R4, new Since(MinecraftVersion.MC1_7_R4, "e"),
             new Since(MinecraftVersion.MC1_12_R1, "save"),
             new Since(MinecraftVersion.MC1_18_R1, "saveWithoutId(net.minecraft.nbt.CompoundTag)")),
     NMS_ENTITY_GETSAVEID(ClassWrapper.NMS_ENTITY, new Class[] {}, MinecraftVersion.MC1_14_R1,
@@ -251,7 +261,7 @@ public enum ReflectionMethod {
 
     PARSE_NBT(ClassWrapper.NMS_MOJANGSONPARSER, new Class[] { String.class }, MinecraftVersion.MC1_7_R4,
             new Since(MinecraftVersion.MC1_7_R4, "parse"),
-            new Since(MinecraftVersion.MC1_18_R1, "parseTag(java.lang.String)")),
+            new Since(MinecraftVersion.MC1_18_R1, "parseTag(java.lang.String)"), new Since(MinecraftVersion.MC1_21_R5, "parseCompoundFully(java.lang.String)")),
     REGISTRY_KEYSET(ClassWrapper.NMS_REGISTRYSIMPLE, new Class[] {}, MinecraftVersion.MC1_11_R1,
             MinecraftVersion.MC1_13_R1, new Since(MinecraftVersion.MC1_11_R1, "keySet")),
     REGISTRY_GET(ClassWrapper.NMS_REGISTRYSIMPLE, new Class[] { Object.class }, MinecraftVersion.MC1_11_R1,
@@ -292,19 +302,41 @@ public enum ReflectionMethod {
     NMSITEM_SET(ClassWrapper.NMS_ITEMSTACK, new Class[] {ClassWrapper.NMS_DATACOMPONENTTYPE.getClazz(), Object.class}, MinecraftVersion.MC1_20_R4,
             new Since(MinecraftVersion.MC1_20_R4, "set(net.minecraft.core.component.DataComponentType,java.lang.Object)")),
     NMSITEM_SAVE_MODERN(ClassWrapper.NMS_ITEMSTACK, new Class[] { ClassWrapper.NMS_PROVIDER.getClazz() },
-            MinecraftVersion.MC1_20_R4, new Since(MinecraftVersion.MC1_20_R4, "save(net.minecraft.core.HolderLookup$Provider)")),
+            MinecraftVersion.MC1_20_R4, MinecraftVersion.MC1_21_R4, new Since(MinecraftVersion.MC1_20_R4, "save(net.minecraft.core.HolderLookup$Provider)")),
     NMSITEM_LOAD(ClassWrapper.NMS_ITEMSTACK, new Class[] { ClassWrapper.NMS_PROVIDER.getClazz(), ClassWrapper.NMS_NBTTAGCOMPOUND.getClazz() },
-            MinecraftVersion.MC1_20_R4, new Since(MinecraftVersion.MC1_20_R4, "parseOptional(net.minecraft.core.HolderLookup$Provider,net.minecraft.nbt.CompoundTag)")),
+            MinecraftVersion.MC1_20_R4, MinecraftVersion.MC1_21_R3, new Since(MinecraftVersion.MC1_20_R4, "parseOptional(net.minecraft.core.HolderLookup$Provider,net.minecraft.nbt.CompoundTag)")),
+    NMSITEM_LOAD_MODERN(ClassWrapper.NMS_ITEMSTACK, new Class[] { ClassWrapper.NMS_PROVIDER.getClazz(), ClassWrapper.NMS_NBTBASE.getClazz() },
+            MinecraftVersion.MC1_21_R4,  MinecraftVersion.MC1_21_R4, new Since(MinecraftVersion.MC1_20_R4, "parse(net.minecraft.core.HolderLookup$Provider,net.minecraft.nbt.Tag)")),
     NMSSERVER_GETREGISTRYACCESS(ClassWrapper.NMS_SERVER, new Class[] {},
             MinecraftVersion.MC1_20_R4, new Since(MinecraftVersion.MC1_20_R4, "registryAccess()")),
     NMSSERVER_GETSERVER(ClassWrapper.CRAFT_SERVER, new Class[] {},
             MinecraftVersion.MC1_20_R4, new Since(MinecraftVersion.MC1_20_R4, "getServer()")),
-    TILEENTITY_GET_NBT_1205(ClassWrapper.NMS_TILEENTITY, new Class[] {ClassWrapper.NMS_PROVIDER.getClazz()}, MinecraftVersion.MC1_20_R4,
+    TILEENTITY_GET_NBT_1205(ClassWrapper.NMS_TILEENTITY, new Class[] {ClassWrapper.NMS_PROVIDER.getClazz()}, MinecraftVersion.MC1_20_R4, MinecraftVersion.MC1_21_R4,
             new Since(MinecraftVersion.MC1_20_R4, "saveWithId(net.minecraft.core.HolderLookup$Provider)")),
     TILEENTITY_SET_NBT_1205(ClassWrapper.NMS_TILEENTITY, new Class[] {ClassWrapper.NMS_NBTTAGCOMPOUND.getClazz(), ClassWrapper.NMS_PROVIDER.getClazz() },
-            MinecraftVersion.MC1_20_R4, new Since(MinecraftVersion.MC1_20_R4, "loadWithComponents(net.minecraft.nbt.CompoundTag,net.minecraft.core.HolderLookup$Provider)")),
+            MinecraftVersion.MC1_20_R4, MinecraftVersion.MC1_21_R4, new Since(MinecraftVersion.MC1_20_R4, "loadWithComponents(net.minecraft.nbt.CompoundTag,net.minecraft.core.HolderLookup$Provider)")),
     GET_DATAFIXER(ClassWrapper.NMS_DATAFIXERS, new Class[] {}, MinecraftVersion.MC1_20_R4,
             new Since(MinecraftVersion.MC1_20_R4, "getDataFixer()")),
+    // 1.21.6 Stuff
+    GET_SERIALIZATION_CONTEXT(ClassWrapper.NMS_PROVIDER, new Class[] {ClassWrapper.NMS_DYNAMICOPS.getClazz()}, MinecraftVersion.MC1_21_R5,
+            new Since(MinecraftVersion.MC1_21_R5, "createSerializationContext(com.mojang.serialization.DynamicOps)")),
+    NMS_GET_TAG_VALUE_INPUT(ClassWrapper.NMS_TAG_VALUE_INPUT, new Class[] {ClassWrapper.NMS_PROBLEM_REPORTER.getClazz(), ClassWrapper.NMS_PROVIDER.getClazz(), ClassWrapper.NMS_NBTTAGCOMPOUND.getClazz()}, MinecraftVersion.MC1_21_R5,
+            new Since(MinecraftVersion.MC1_21_R5, "create(net.minecraft.util.ProblemReporter,net.minecraft.core.HolderLookup$Provider,net.minecraft.nbt.CompoundTag)")),
+    NMS_GET_TAG_VALUE_OUTPUT(ClassWrapper.NMS_TAG_VALUE_OUTPUT, new Class[] {ClassWrapper.NMS_PROBLEM_REPORTER.getClazz(), ClassWrapper.NMS_PROVIDER.getClazz()}, MinecraftVersion.MC1_21_R5,
+            new Since(MinecraftVersion.MC1_21_R5, "createWithContext(net.minecraft.util.ProblemReporter,net.minecraft.core.HolderLookup$Provider)")),
+    NMS_TAG_VALUE_OUTPUT_TO_TAG_COMPOUND(ClassWrapper.NMS_TAG_VALUE_OUTPUT, new Class[] {}, MinecraftVersion.MC1_21_R5,
+            new Since(MinecraftVersion.MC1_21_R5, "buildResult()")),
+    NMS_ENTITY_SET_NBT_1216(ClassWrapper.NMS_ENTITY, new Class[] { ClassWrapper.NMS_VALUE_INPUT.getClazz() }, MinecraftVersion.MC1_21_R5,
+            new Since(MinecraftVersion.MC1_21_R5, "load(net.minecraft.world.level.storage.ValueInput)")
+    ),
+    NMS_ENTITY_GET_NBT_1216(ClassWrapper.NMS_ENTITY, new Class[] { ClassWrapper.NMS_VALUE_OUTPUT.getClazz() }, MinecraftVersion.MC1_21_R5,
+            new Since(MinecraftVersion.MC1_21_R5, "saveWithoutId(net.minecraft.world.level.storage.ValueOutput)")),
+
+    TILEENTITY_GET_NBT_1216(ClassWrapper.NMS_TILEENTITY, new Class[] {ClassWrapper.NMS_VALUE_OUTPUT.getClazz()}, MinecraftVersion.MC1_21_R5,
+            new Since(MinecraftVersion.MC1_21_R5, "saveWithId(net.minecraft.world.level.storage.ValueOutput)")),
+    TILEENTITY_SET_NBT_1216(ClassWrapper.NMS_TILEENTITY, new Class[] {ClassWrapper.NMS_VALUE_INPUT.getClazz() },
+            MinecraftVersion.MC1_21_R5,
+            new Since(MinecraftVersion.MC1_21_R5, "loadWithComponents(net.minecraft.world.level.storage.ValueInput)")),
     ;
 
     private MinecraftVersion removedAfter;
@@ -382,6 +414,16 @@ public enum ReflectionMethod {
         this(targetClass, args, addedSince, null, methodnames);
     }
 
+    private static String resolveItemStackBukkitMirrorMethodName() {
+        try {
+            ClassWrapper.CRAFT_ITEMSTACK.getClazz().getDeclaredMethod("asCraftMirror",
+                    ClassWrapper.NMS_ITEMSTACK.getClazz());
+            return "asCraftMirror";
+        } catch (NullPointerException | NoSuchMethodException | SecurityException ignored) {
+            return "asBukkitMirror";
+        }
+    }
+
     /**
      * Runs the method on a given target object using the given args.
      * 
@@ -396,7 +438,8 @@ public enum ReflectionMethod {
             return method.invoke(target, args);
         } catch (Exception ex) {
             throw new NbtApiException("Error while calling the method '" + methodName + "', loaded: " + loaded
-                    + ", Enum: " + this + ", Passed Class: " + (target == null ? "null" : target.getClass()) + " Args: " + (args == null ? "null" : Arrays.toString(args)), ex);
+                    + ", Enum: " + this + ", Passed Class: " + (target == null ? "null" : target.getClass()) + " Args: " + (args == null ? "null" : Arrays.toString(args)) + 
+                    " Classes: " + (args == null ? "null" : Arrays.asList(args).stream().map(a -> a == null ? "NULL" : a.getClass().getName()).collect(Collectors.toList())), ex);
         }
     }
 

item-nbt-plugin/pom.xml

@@ -4,7 +4,7 @@
   <parent>
     <groupId>de.tr7zw</groupId>
     <artifactId>item-nbt-parent</artifactId>
-    <version>2.14.0</version>
+    <version>2.16.1</version>
   </parent>
   <artifactId>item-nbt-api-plugin</artifactId>
   <packaging>jar</packaging>
@@ -12,7 +12,7 @@
     <dependency>
       <groupId>de.tr7zw</groupId>
       <artifactId>item-nbt-api</artifactId>
-      <version>2.14.0</version>
+      <version>2.16.1</version>
       <scope>compile</scope>
     </dependency>
     <dependency>
@@ -21,6 +21,13 @@
 	    <version>4.0.26</version>
 	    <scope>provided</scope>
 	</dependency>
+  <dependency>
+	  <groupId>org.bstats</groupId>
+	  <artifactId>bstats-bukkit</artifactId>
+	  <version>3.2.1</version>
+    <!-- Overwrite to provided -->
+	  <scope>provided</scope>
+	</dependency>
   </dependencies>
   <build>
     <resources>
@@ -33,7 +40,7 @@
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-shade-plugin</artifactId>
-        <version>3.6.0</version>
+        <version>3.6.2</version>
         <configuration>
           <createDependencyReducedPom>true</createDependencyReducedPom>
           <relocations>
@@ -41,14 +48,6 @@
               <pattern>de.tr7zw.changeme.nbtapi</pattern>
               <shadedPattern>de.tr7zw.nbtapi</shadedPattern>
             </relocation>
-            <relocation>
-              <pattern>javassist</pattern>
-              <shadedPattern>de.tr7zw.nbtinjector.javassist</shadedPattern>
-            </relocation>
-            <relocation>
-              <pattern>de.tr7zw.annotations</pattern>
-              <shadedPattern>de.tr7zw.nbtapi.utils.annotations</shadedPattern>
-            </relocation>
           </relocations>
           <transformers>
             <transformer implementation="org.apache.maven.plugins.shade.resource.AppendingTransformer">

item-nbt-plugin/src/main/java/de/tr7zw/nbtapi/plugin/NBTAPI.java

@@ -7,7 +7,6 @@ import java.util.Map;
 import java.util.Map.Entry;
 import java.util.logging.Level;
 
-import org.bukkit.Bukkit;
 import org.bukkit.plugin.java.JavaPlugin;
 
 import de.tr7zw.changeme.nbtapi.NbtApiException;
@@ -19,6 +18,7 @@ import de.tr7zw.nbtapi.plugin.tests.GameprofileTest;
 import de.tr7zw.nbtapi.plugin.tests.NBTFileTest;
 import de.tr7zw.nbtapi.plugin.tests.blocks.BlockNBTTest;
 import de.tr7zw.nbtapi.plugin.tests.chunks.ChunkNBTPersistentTest;
+import de.tr7zw.nbtapi.plugin.tests.compounds.CompoundDifferenceTest;
 import de.tr7zw.nbtapi.plugin.tests.compounds.EnumTest;
 import de.tr7zw.nbtapi.plugin.tests.compounds.EqualsTest;
 import de.tr7zw.nbtapi.plugin.tests.compounds.ForEachTest;
@@ -41,6 +41,7 @@ import de.tr7zw.nbtapi.plugin.tests.items.DirectApplyMetaTest;
 import de.tr7zw.nbtapi.plugin.tests.items.DirectApplyTest;
 import de.tr7zw.nbtapi.plugin.tests.items.EmptyItemTest;
 import de.tr7zw.nbtapi.plugin.tests.items.ItemConversionTest;
+import de.tr7zw.nbtapi.plugin.tests.items.ItemJsonTest;
 import de.tr7zw.nbtapi.plugin.tests.items.ItemMergingTest;
 import de.tr7zw.nbtapi.plugin.tests.items.ItemStackConversionTest;
 import de.tr7zw.nbtapi.plugin.tests.items.LegacyItemTest;
@@ -99,6 +100,7 @@ public class NBTAPI extends JavaPlugin {
         apiTests.add(new ForEachTest());
         apiTests.add(new StreamTest());
         apiTests.add(new EqualsTest());
+        apiTests.add(new CompoundDifferenceTest());
         if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_8_R3)) // 1.7.10 list support is not complete at all
             apiTests.add(new IteratorTest());
         if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_16_R1))
@@ -112,6 +114,9 @@ public class NBTAPI extends JavaPlugin {
         if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_20_R4)) {
             apiTests.add(new LegacyItemTest());
         }
+        if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_20_R4) && !MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_21_R4)) {
+            apiTests.add(new ItemJsonTest());
+        }
         apiTests.add(new ComponentsTest());
         apiTests.add(new EmptyItemTest());
         apiTests.add(new SmuggleTest());
@@ -195,7 +200,7 @@ public class NBTAPI extends JavaPlugin {
             } catch (Exception ex) {
                 results.put(test, ex);
                 getLogger().log(Level.WARNING, "Error during '" + test.getClass().getSimpleName() + "' test!", ex);
-            } catch (NoSuchFieldError th) { // NOSONAR
+            } catch (Throwable th) { // NOSONAR
                 getLogger().log(Level.SEVERE, "Servere error during '" + test.getClass().getSimpleName() + "' test!");
                 getLogger().warning(
                         "WARNING! This version of Item-NBT-API seems to be broken with your Spigot version! Canceled the other tests!");

item-nbt-plugin/src/main/java/de/tr7zw/nbtapi/plugin/tests/GameprofileTest.java

@@ -15,9 +15,8 @@ public class GameprofileTest implements Test {
         UUID uuid = UUID.randomUUID();
         GameProfile profile = new GameProfile(uuid, "random");
         ReadWriteNBT nbt = NBT.gameProfileToNBT(profile);
-        profile = null;
-        profile = NBT.gameProfileFromNBT(nbt);
-        if (profile == null || !profile.getId().equals(uuid)) {
+        GameProfile profile2 = NBT.gameProfileFromNBT(nbt);
+        if (profile == null || !profile.equals(profile2)) {
             throw new NbtApiException("Error when converting a GameProfile from/to NBT!");
         }
     }

item-nbt-plugin/src/main/java/de/tr7zw/nbtapi/plugin/tests/blocks/BlockNBTTest.java

@@ -1,40 +1,77 @@
 package de.tr7zw.nbtapi.plugin.tests.blocks;
 
+import de.tr7zw.changeme.nbtapi.NBT;
+import de.tr7zw.changeme.nbtapi.NBTType;
+import de.tr7zw.changeme.nbtapi.iface.ReadableNBT;
 import org.bukkit.Bukkit;
 import org.bukkit.Chunk;
 import org.bukkit.World;
 import org.bukkit.block.Block;
 
-import de.tr7zw.changeme.nbtapi.NBTBlock;
 import de.tr7zw.changeme.nbtapi.NbtApiException;
 import de.tr7zw.changeme.nbtapi.utils.MinecraftVersion;
 import de.tr7zw.nbtapi.plugin.tests.Test;
 
+import java.util.List;
+
 public class BlockNBTTest implements Test {
 
     @Override
     public void test() throws Exception {
         if (MinecraftVersion.getVersion().getVersionId() < MinecraftVersion.MC1_16_R3.getVersionId())
             return;
-        if (!Bukkit.getWorlds().isEmpty()) {
-            World world = Bukkit.getWorlds().get(0);
-            try {
-                if (world.getLoadedChunks().length > 1) {
-                    Chunk chunk = world.getLoadedChunks()[0];
-                    Block block = chunk.getBlock(0, 254, 0);
-                    NBTBlock comp = new NBTBlock(block);
-                    comp.getData().removeKey("Too");
-                    if (comp.getData().hasTag("Too")) {
-                        throw new NbtApiException("Unable to remove key from Block!");
-                    }
-                    comp.getData().setString("Too", "Bar");
-                    if (!new NBTBlock(block).getData().getString("Too").equals("Bar")) {
-                        throw new NbtApiException("Custom Data did not save to a Block!");
-                    }
-                }
-            } catch (Exception ex) {
-                throw new NbtApiException("Wasn't able to use NBTBlocks!", ex);
+
+        List<World> loadedWorlds = Bukkit.getWorlds();
+        if (loadedWorlds.isEmpty())
+            return;
+
+        World world = loadedWorlds.get(0);
+        Chunk[] loadedChunks = world.getLoadedChunks();
+        if (loadedChunks.length == 0)
+            return;
+
+        try {
+            Chunk chunk = loadedChunks[0];
+            Block block = chunk.getBlock(0, 254, 0);
+            String blockKey = block.getX() + "_" + block.getY() + "_" + block.getZ();
+
+            NBT.modifyChunkPDC(block, nbt -> nbt.setString("Too", "Bar"));
+            boolean storedDataPresent = NBT.readAndGetChunkPDC(chunk, nbt -> {
+                if (!nbt.hasTag("blocks", NBTType.NBTTagCompound)) return false;
+
+                ReadableNBT blocksNbt = nbt.getCompound("blocks");
+                if (blocksNbt == null || !blocksNbt.hasTag(blockKey,  NBTType.NBTTagCompound)) return false;
+
+                ReadableNBT blockNbt =  blocksNbt.getCompound(blockKey);
+                return blockNbt != null && blockNbt.hasTag("Too", NBTType.NBTTagString) && "Bar".equals(blockNbt.getString("Too"));
+            });
+            if (!storedDataPresent) {
+                throw new NbtApiException("Custom Data did not save to a Block!");
             }
+            if (!NBT.readAndGetChunkPDC(block, nbt -> nbt.hasTag("Too"))) {
+                throw new NbtApiException("Custom Data did not save to a Block!");
+            }
+
+            boolean blockHadOnlyTestKey = NBT.readAndGetChunkPDC(block, nbt -> nbt.getKeys().size() == 1);
+            boolean chunkHadOnlyOneBlock = NBT.readAndGetChunkPDC(chunk, nbt -> nbt.getCompound("blocks").getKeys().size() == 1);
+
+            NBT.modifyChunkPDC(block, nbt -> nbt.removeKey("Too"));
+
+            if (NBT.readAndGetChunkPDC(block, nbt -> nbt.hasTag("Too"))) {
+                throw new NbtApiException("Unable to remove key from Block!");
+            }
+
+            if (chunkHadOnlyOneBlock) {
+               if (NBT.readAndGetChunkPDC(chunk, nbt -> nbt.hasTag("blocks"))) {
+                    throw new NbtApiException("Chunk data wasn't cleaned up (hanging \"blocks\" compound)!");
+                }
+            } else if (blockHadOnlyTestKey) {
+                if (NBT.readAndGetChunkPDC(chunk, nbt -> nbt.getCompound("blocks").hasTag(blockKey))) {
+                    throw new NbtApiException("Chunk data wasn't cleaned up (hanging block location compound)!");
+                }
+            }
+        } catch (Exception ex) {
+            throw new NbtApiException("Wasn't able to use NBTBlocks!", ex);
         }
     }
 

item-nbt-plugin/src/main/java/de/tr7zw/nbtapi/plugin/tests/chunks/ChunkNBTPersistentTest.java

@@ -1,40 +1,46 @@
 package de.tr7zw.nbtapi.plugin.tests.chunks;
 
+import de.tr7zw.changeme.nbtapi.NBT;
+import de.tr7zw.changeme.nbtapi.NBTType;
 import org.bukkit.Bukkit;
 import org.bukkit.Chunk;
 import org.bukkit.World;
 
-import de.tr7zw.changeme.nbtapi.NBTChunk;
-import de.tr7zw.changeme.nbtapi.NBTCompound;
 import de.tr7zw.changeme.nbtapi.NbtApiException;
 import de.tr7zw.changeme.nbtapi.utils.MinecraftVersion;
 import de.tr7zw.nbtapi.plugin.tests.Test;
 
+import java.util.List;
+
 public class ChunkNBTPersistentTest implements Test {
 
     @Override
     public void test() throws Exception {
         if (MinecraftVersion.getVersion().getVersionId() < MinecraftVersion.MC1_16_R3.getVersionId())
             return;
-        if (!Bukkit.getWorlds().isEmpty()) {
-            World world = Bukkit.getWorlds().get(0);
-            try {
-                if (world.getLoadedChunks().length > 1) {
-                    Chunk chunk = world.getLoadedChunks()[0];
-                    NBTChunk comp = new NBTChunk(chunk);
-                    NBTCompound persistentData = comp.getPersistentDataContainer();
-                    persistentData.removeKey("Foo");
-                    if (persistentData.hasTag("Foo")) {
-                        throw new NbtApiException("Unable to remove key from Chunk!");
-                    }
-                    persistentData.setString("Foo", "Bar");
-                    if (!new NBTChunk(chunk).getPersistentDataContainer().getString("Foo").equals("Bar")) {
-                        throw new NbtApiException("Custom Data did not save to the Chunk!");
-                    }
-                }
-            } catch (Exception ex) {
-                throw new NbtApiException("Wasn't able to use NBTChunks!", ex);
+
+        List<World> loadedWorlds = Bukkit.getWorlds();
+        if (loadedWorlds.isEmpty())
+            return;
+
+        World world = loadedWorlds.get(0);
+        Chunk[] loadedChunks = world.getLoadedChunks();
+        if (loadedChunks.length == 0)
+            return;
+
+        Chunk chunk = loadedChunks[0];
+        try {
+            NBT.modifyChunkPDC(chunk, nbt -> nbt.setString("Foo", "Bar"));
+            if (!NBT.readAndGetChunkPDC(chunk, nbt -> nbt.hasTag("Foo", NBTType.NBTTagString) && "Bar".equals(nbt.getString("Foo")))) {
+                throw new NbtApiException("Custom Data did not save to the Chunk!");
             }
+
+            NBT.modifyChunkPDC(chunk, nbt -> nbt.removeKey("Foo"));
+            if (NBT.readAndGetChunkPDC(chunk, nbt -> nbt.hasTag("Foo"))) {
+                throw new NbtApiException("Unable to remove key from Chunk!");
+            }
+        } catch (Exception ex) {
+            throw new NbtApiException("Wasn't able to use NBTChunks!", ex);
         }
     }
 

item-nbt-plugin/src/main/java/de/tr7zw/nbtapi/plugin/tests/compounds/CompoundDifferenceTest.java

@@ -0,0 +1,69 @@
+package de.tr7zw.nbtapi.plugin.tests.compounds;
+
+import de.tr7zw.changeme.nbtapi.NBT;
+import de.tr7zw.changeme.nbtapi.NbtApiException;
+import de.tr7zw.changeme.nbtapi.iface.ReadWriteNBT;
+import de.tr7zw.nbtapi.plugin.tests.Test;
+
+import java.util.Arrays;
+
+public class CompoundDifferenceTest implements Test {
+
+	@Override
+	public void test() throws Exception {
+		ReadWriteNBT nbt1 = NBT.createNBTObject();
+		nbt1.setInteger("intTag", 1);
+		ReadWriteNBT tmp = NBT.createNBTObject();
+		tmp.setInteger("foo", 1);
+		nbt1.getCompoundList("compoundList1").addCompound(tmp);
+		nbt1.setIntArray("intArray", new int[]{1, 2, 3});
+		tmp = NBT.createNBTObject();
+		tmp.setIntArray("foo", new int[]{1, 2, 3});
+		nbt1.getCompoundList("compoundList2").addCompound(tmp);
+		nbt1.getOrCreateCompound("compoundTag").setFloat("floatTag", 20F);
+		nbt1.getOrCreateCompound("compoundTag").setBoolean("booleanTag", true);
+		nbt1.getOrCreateCompound("compoundTag").getDoubleList("doubleList").addAll(Arrays.asList(1D, 2D, 3D));
+		nbt1.getOrCreateCompound("compoundTag").getFloatList("floatList").addAll(Arrays.asList(1F, 2F));
+		nbt1.getOrCreateCompound("compoundTagTwo").setString("stringTag", "string");
+		ReadWriteNBT nbt2 = NBT.createNBTObject();
+		nbt2.setInteger("intTag", 1);
+		tmp = NBT.createNBTObject();
+		tmp.setInteger("foo", 1);
+		nbt2.getCompoundList("compoundList1").addCompound(tmp);
+		nbt2.setInteger("alsoIntTag", 2);
+		tmp = NBT.createNBTObject();
+		tmp.setInteger("foo", 2);
+		nbt2.getCompoundList("compoundList2").addCompound(tmp);
+		nbt2.getOrCreateCompound("compoundTag").setFloat("floatTag", 20F);
+		nbt2.getOrCreateCompound("compoundTag").setBoolean("booleanTag", false);
+		nbt2.getOrCreateCompound("compoundTag").getDoubleList("doubleList").addAll(Arrays.asList(1D, 2D, 3D, 4D));
+		nbt2.getOrCreateCompound("compoundTag").getFloatList("floatList").addAll(Arrays.asList(1F, 2F));
+		nbt2.getOrCreateCompound("compoundTagTwo").setString("stringTag", "string");
+
+		ReadWriteNBT expectedDiff1 = NBT.createNBTObject();
+		tmp = NBT.createNBTObject();
+		tmp.setIntArray("foo", new int[]{1, 2, 3});
+		expectedDiff1.getCompoundList("compoundList2").addCompound(tmp);
+		expectedDiff1.setIntArray("intArray", new int[]{1, 2, 3});
+		expectedDiff1.getOrCreateCompound("compoundTag").setBoolean("booleanTag", true);
+		expectedDiff1.getOrCreateCompound("compoundTag").getDoubleList("doubleList").addAll(Arrays.asList(1D, 2D, 3D));
+		ReadWriteNBT expectedDiff2 = NBT.createNBTObject();
+		tmp = NBT.createNBTObject();
+		tmp.setInteger("foo", 2);
+		expectedDiff2.getCompoundList("compoundList2").addCompound(tmp);
+		expectedDiff2.setInteger("alsoIntTag", 2);
+		expectedDiff2.getOrCreateCompound("compoundTag").setBoolean("booleanTag", false);
+		expectedDiff2.getOrCreateCompound("compoundTag").getDoubleList("doubleList").addAll(Arrays.asList(1D, 2D, 3D, 4D));
+
+		ReadWriteNBT diff1 = nbt1.extractDifference(nbt2);
+		ReadWriteNBT diff2 = nbt2.extractDifference(nbt1);
+
+		if (!expectedDiff1.equals(diff1)) {
+			throw new NbtApiException("Diff1: Compounds did not match! " + expectedDiff1 + " " + diff1);
+		}
+		if (!expectedDiff2.equals(diff2)) {
+			throw new NbtApiException("Diff2: Compounds did not match! " + expectedDiff2 + " " + diff2);
+		}
+	}
+
+}

item-nbt-plugin/src/main/java/de/tr7zw/nbtapi/plugin/tests/compounds/ListTest.java

@@ -71,7 +71,7 @@ public class ListTest implements Test {
         }
 
         if (comp.getListType("complist") != NBTType.NBTTagCompound) {
-            throw new NbtApiException("complist had the wrong type! The Item-NBT-API may not work!");
+            throw new NbtApiException("complist had the wrong type(" + comp.getListType("complist") + ")! The Item-NBT-API may not work!");
         }
 
         // Integer

item-nbt-plugin/src/main/java/de/tr7zw/nbtapi/plugin/tests/compounds/StreamTest.java

@@ -7,21 +7,21 @@ import org.bukkit.Material;
 import org.bukkit.inventory.ItemStack;
 
 import de.tr7zw.changeme.nbtapi.NBT;
-import de.tr7zw.changeme.nbtapi.NBTContainer;
 import de.tr7zw.changeme.nbtapi.NbtApiException;
+import de.tr7zw.changeme.nbtapi.iface.ReadWriteNBT;
 import de.tr7zw.nbtapi.plugin.tests.Test;
 
 public class StreamTest implements Test {
 
     @Override
     public void test() throws Exception {
-        NBTContainer base = new NBTContainer();
+        ReadWriteNBT base = NBT.createNBTObject();
         base.getOrCreateCompound("sub").setString("hello", "world");
         ByteArrayOutputStream outStream = new ByteArrayOutputStream();
         base.getOrCreateCompound("sub").writeCompound(outStream);
         byte[] data = outStream.toByteArray();
         ByteArrayInputStream inputStream = new ByteArrayInputStream(data);
-        NBTContainer container = new NBTContainer(inputStream);
+        ReadWriteNBT container = NBT.readNBT(inputStream);
         if (!container.toString().equals(base.getOrCreateCompound("sub").toString())) {
             throw new NbtApiException("Component content did not match! " + base.getCompound("sub") + " " + container);
         }

item-nbt-plugin/src/main/java/de/tr7zw/nbtapi/plugin/tests/items/ComponentsTest.java

@@ -27,7 +27,11 @@ public class ComponentsTest implements Test {
             throw new NbtApiException("ReadComponent didn't work!");
         }
         NBT.modifyComponents(item, nbt -> {
-            nbt.setString("minecraft:custom_name", "{\"extra\":[\"foobar\"],\"text\":\"\"}");
+            if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_21_R4)) {
+                nbt.mergeCompound(NBT.parseNBT("{\"minecraft:custom_name\":[{\"text\":\"foobar\",\"italic\":false}]}"));
+            } else {
+                nbt.setString("minecraft:custom_name", "{\"extra\":[\"foobar\"],\"text\":\"\"}");
+            }
         });
         if(!item.getItemMeta().getDisplayName().equals("foobar")) {
             throw new NbtApiException("ModifyComponent didn't work!");

item-nbt-plugin/src/main/java/de/tr7zw/nbtapi/plugin/tests/items/ItemConversionTest.java

@@ -1,13 +1,15 @@
 package de.tr7zw.nbtapi.plugin.tests.items;
 
+import de.tr7zw.changeme.nbtapi.NBT;
+import de.tr7zw.changeme.nbtapi.NBTType;
+import de.tr7zw.changeme.nbtapi.iface.ReadWriteNBT;
+import de.tr7zw.changeme.nbtapi.utils.MinecraftVersion;
 import org.bukkit.Material;
 import org.bukkit.inventory.ItemStack;
 import org.bukkit.inventory.meta.ItemMeta;
 
 import com.google.common.collect.Lists;
 
-import de.tr7zw.changeme.nbtapi.NBTContainer;
-import de.tr7zw.changeme.nbtapi.NBTItem;
 import de.tr7zw.changeme.nbtapi.NbtApiException;
 import de.tr7zw.nbtapi.plugin.tests.Test;
 
@@ -19,14 +21,21 @@ public class ItemConversionTest implements Test {
         ItemMeta meta = item.getItemMeta();
         meta.setLore(Lists.newArrayList("Firest Line", "Second Line"));
         item.setItemMeta(meta);
-        String nbt = NBTItem.convertItemtoNBT(item).toString();
-        if (!nbt.contains("Firest Line") || !nbt.contains("Second Line"))
-            throw new NbtApiException("The Item nbt '" + nbt + "' didn't contain the lore");
-        ItemStack rebuild = NBTItem.convertNBTtoItem(new NBTContainer(nbt));
+
+        ReadWriteNBT nbt = NBT.itemStackToNBT(item);
+        if (MinecraftVersion.isAtLeastVersion(MinecraftVersion.MC1_12_R1)
+                && !nbt.hasTag("DataVersion", NBTType.NBTTagInt)) {
+            throw new NbtApiException("The item nbt '" + nbt + "' didn't contain the data version");
+        }
+
+        String nbtString = nbt.toString();
+        if (!nbtString.contains("Firest Line") || !nbtString.contains("Second Line"))
+            throw new NbtApiException("The Item nbt '" + nbtString + "' didn't contain the lore");
+        ItemStack rebuild = NBT.itemStackFromNBT(NBT.parseNBT(nbtString));
         if (!item.isSimilar(rebuild))
             throw new NbtApiException("Rebuilt item did not match the original!");
 
-        NBTContainer cont = new NBTContainer();
+        ReadWriteNBT cont = NBT.createNBTObject();
         cont.setItemStack("testItem", item);
         if (!item.isSimilar(cont.getItemStack("testItem")))
             throw new NbtApiException("Rebuilt item did not match the original!");

item-nbt-plugin/src/main/java/de/tr7zw/nbtapi/plugin/tests/items/ItemJsonTest.java

@@ -0,0 +1,28 @@
+package de.tr7zw.nbtapi.plugin.tests.items;
+
+import org.bukkit.Material;
+import org.bukkit.inventory.ItemStack;
+import org.bukkit.inventory.meta.ItemMeta;
+
+import com.google.gson.JsonElement;
+
+import de.tr7zw.changeme.nbtapi.NbtApiException;
+import de.tr7zw.changeme.nbtapi.utils.NBTJsonUtil;
+import de.tr7zw.nbtapi.plugin.tests.Test;
+
+public class ItemJsonTest implements Test {
+
+    @Override
+    public void test() throws Exception {
+        ItemStack item = new ItemStack(Material.STONE);
+        ItemMeta meta = item.getItemMeta();
+        meta.setDisplayName("test");
+        meta.setUnbreakable(true);
+        item.setItemMeta(meta);
+        JsonElement elem = NBTJsonUtil.itemStackToJson(item);
+        if (elem == null) {
+            throw new NbtApiException("Getting the Json didn't work correctly! " + item);
+        }
+    }
+
+}

item-nbt-plugin/src/main/java/de/tr7zw/nbtapi/plugin/tests/items/LegacyItemTest.java

@@ -29,6 +29,15 @@ public class LegacyItemTest implements Test {
                 || !"test".equals(item.getItemMeta().getDisplayName())) {
             throw new NbtApiException("1.12.2 item didn't load correctly! " + item);
         }
+
+        ItemStack item2 = NBT.itemStackFromNBT(NBT.parseNBT("{DataVersion:" + DataFixerUtil.VERSION1_12_2 + ",id:cobblestone,Count:42,tag:{display:{Name:\"test\"},ench:[{lvl:3,id:34}]}}"));
+        if (!item.equals(item2))
+            throw new NbtApiException("Data-fixed 1.12.2 item didn't load correctly! " + item2);
+        
+        ReadWriteNBT testNBT = NBT.parseNBT("{id:cobblestone,Count:42,tag:{display:{Name:\"test\"},ench:[{lvl:3,id:34}]},DataVersion:1343}");
+        testNBT = DataFixerUtil.fixUpItemData(testNBT, DataFixerUtil.VERSION1_12R1);
+        if (testNBT.getInteger("DataVersion") != DataFixerUtil.getCurrentVersion())
+            throw new NbtApiException("DataVersion wasn't updated correctly! " + testNBT);
     }
 
 }

mappings-parser/pom.xml

@@ -4,7 +4,7 @@
   <parent>
     <groupId>de.tr7zw</groupId>
     <artifactId>item-nbt-parent</artifactId>
-    <version>2.14.0</version>
+    <version>2.16.1</version>
   </parent>
   <artifactId>mappings-parser</artifactId>
   <packaging>jar</packaging>
@@ -12,7 +12,7 @@
     <dependency>
       <groupId>de.tr7zw</groupId>
       <artifactId>item-nbt-api</artifactId>
-      <version>2.14.0</version>
+      <version>2.16.1</version>
       <scope>compile</scope>
     </dependency>
   </dependencies>

mappings-parser/src/main/java/dev/tr7zw/mappingsparser/MappingsParser.java

@@ -24,7 +24,7 @@ public class MappingsParser {
     public static StringBuilder builder = new StringBuilder();
 
     public static void main(String[] args) throws IOException {
-        File input = new File("minecraft_server.1.21.2.txt");
+        File input = new File("minecraft_server.1.21.9.txt");
         List<String> lines = Files.readAllLines(input.toPath());
 
         Map<String, ClassWrapper> classes = new HashMap<>();
@@ -75,6 +75,33 @@ public class MappingsParser {
             }
             // System.out.println(currentClass + ": " + mojangName + " -> " + unmappedName);
         }
+        for(String type : MojangToMapping.getMapping().keySet()) {
+            if(type.contains("(")) {
+                continue;
+            }
+            // Field
+            String clazz = type.split("#")[0];
+            String fieldName = type.split("#")[1];
+            for (String line : lines) {
+                if (line.startsWith("#")) {
+                    continue;
+                }
+                if (!line.startsWith(" ")) {
+                    currentClass = line.split(" ")[0];
+                    continue;
+                }
+                mojangName = line.trim().split(" ")[1];
+                unmappedName = line.trim().split(" ")[3];
+                if (currentClass.equals(clazz) && mojangName.equals(fieldName)) {
+                    if (MojangToMapping.getMapping().get(type) == null) {
+                        System.out.println("Missing mapping for " + type);
+                    } else if (!MojangToMapping.getMapping().get(type)
+                            .equals(unmappedName)) {
+                        builder.append("put(\"" + type + "\", \"" + unmappedName + "\");\n");
+                    }
+                }
+            }
+        }
         System.out.println(builder);
     }
 

nbt-data-api/pom.xml

@@ -5,7 +5,7 @@
   <parent>
     <groupId>de.tr7zw</groupId>
     <artifactId>item-nbt-parent</artifactId>
-    <version>2.14.0</version>
+    <version>2.16.1</version>
   </parent>
 
   <artifactId>nbt-data-api</artifactId>
@@ -14,7 +14,7 @@
     <dependency>
       <groupId>de.tr7zw</groupId>
       <artifactId>item-nbt-api</artifactId>
-      <version>2.14.0</version>
+      <version>2.16.1</version>
       <scope>compile</scope>
     </dependency>
   </dependencies>

nbt-injector/pom.xml

@@ -4,7 +4,7 @@
   <parent>
     <groupId>de.tr7zw</groupId>
     <artifactId>item-nbt-parent</artifactId>
-    <version>2.14.0</version>
+    <version>2.16.1</version>
   </parent>
   <artifactId>nbt-injector</artifactId>
   <packaging>jar</packaging>
@@ -12,7 +12,7 @@
     <dependency>
       <groupId>de.tr7zw</groupId>
       <artifactId>item-nbt-api</artifactId>
-      <version>2.14.0</version>
+      <version>2.16.1</version>
       <scope>compile</scope>
     </dependency>
     <dependency>

pom.xml

@@ -3,7 +3,7 @@
   <modelVersion>4.0.0</modelVersion>
   <groupId>de.tr7zw</groupId>
   <artifactId>item-nbt-parent</artifactId>
-  <version>2.14.0</version>
+  <version>2.16.1</version>
   <packaging>pom</packaging>
   <inceptionYear>2015</inceptionYear>
   <organization>
@@ -88,7 +88,7 @@
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-compiler-plugin</artifactId>
-        <version>3.13.0</version>
+        <version>3.16.0</version>
         <configuration>
           <source>1.8</source>
           <target>1.8</target>
@@ -97,7 +97,7 @@
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-source-plugin</artifactId>
-        <version>3.3.1</version>
+        <version>3.4.0</version>
         <executions>
           <execution>
             <id>attach-sources</id>
@@ -110,7 +110,7 @@
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-javadoc-plugin</artifactId>
-        <version>3.10.1</version>
+        <version>3.12.0</version>
         <configuration>
           <source>8</source>
         </configuration>
@@ -139,7 +139,7 @@
       <plugin>
         <groupId>org.codehaus.mojo</groupId>
         <artifactId>license-maven-plugin</artifactId>
-        <version>2.4.0</version>
+        <version>2.7.1</version>
         <configuration>
           <licenseName>mit</licenseName>
           <licenseFile>LICENSE</licenseFile>

spigot.bb

@@ -112,7 +112,7 @@ Just use the Plugin as Maven dependency and remember to add "NBTAPI" as dependen
 <dependency>
   <groupId>de.tr7zw</groupId>
   <artifactId>item-nbt-api-plugin</artifactId>
-  <version>2.14.0</version>
+  <version>2.16.1</version>
 </dependency>
 [/CODE]
 [/SPOILER]
@@ -122,7 +122,7 @@ Using this method the API gets copied into your plugin. Server owners don't have
 <dependency>
   <groupId>de.tr7zw</groupId>
   <artifactId>item-nbt-api</artifactId>
-  <version>2.14.0</version>
+  <version>2.16.1</version>
 </dependency>
 ...
     <plugins>

wiki/Example-Usages.md

@@ -100,7 +100,7 @@ NBT.modifyPersistentData(zombie, nbt -> {
 File worldDataFolder = Bukkit.getWorlds().getFirst().getWorldFolder();
 
 // Read level data
-NBTFile levelNbtFile = new NBTFile(new File(worldDataFolder, "level.dat"));
+NBTFileHandle levelNbtFile = NBT.getFileHandle(new File(worldDataFolder, "level.dat"));
 
 // Obtain world name
 String worldName = levelNbtFile.resolveOrNull("Data.LevelName", String.class);
@@ -113,7 +113,7 @@ if (!playerFile.exists()) {
     return;
 }
 
-NBTFile playerNbtFile = new NBTFile(playerFile);
+NBTFileHandle playerNbtFile = NBT.getFileHandle(playerFile);
 
 // Change player's health
 float health = playerNbtFile.getFloat("Health");

wiki/FAQ.md

@@ -21,6 +21,4 @@ The experimental NBTInjector became unsupported since Minecraft 1.14 and was rem
 
 NBTInjector is incompatible with reloads and may break things, and thus is not recommended.
 
-If you're using Minecraft 1.14+, you should switch to the persistent storage API instead.
-
-In versions prior to 1.14, you may use a workaround like storing data inside an item's nbt that the entity is wearing (e.g. having a button in mob's helmet, and storing data on that button).
+See [this wiki section](https://github.com/tr7zw/Item-NBT-API/wiki/Using-the-NBT-API#accessing-custom-data) on how to handle custom entity nbt data without NBTInjector.

wiki/Plugins.md

@@ -2,9 +2,11 @@
 
 - [IllegalStack](https://github.com/dniym/IllegalStack)
 - [Prison](https://github.com/PrisonTeam/Prison)
-- [CommandAPI](https://github.com/JorelAli/CommandAPI)
+- [CommandAPI](https://github.com/CommandAPI/CommandAPI)
 - [SkBee](https://github.com/ShaneBeee/SkBee/)
 - [Monumenta](https://github.com/TeamMonumenta/monumenta-plugins-public/)
+- [SummonFriendlyMobs](https://github.com/ArmyFury/SummonFriendlyMobs)
+- [EvenMoreFish](https://github.com/Oheers/EvenMoreFish)
 
 ___
 

wiki/Using-Gradle.md

@@ -2,8 +2,11 @@ To start using NB-API, you either need to depend on its plugin version, or shade
 
 > [!IMPORTANT]
 > Plugin and shaded versions have different ``artifactId``. Make sure to correctly choose the one you need!
+>
+> [!IMPORTANT]
+> Alternative ways of loading the api like Libby are not supported on Discord/Github issues.
 
-# Option 1) NBT-API as a dependency
+# Option 1) NBT-API as a dependency (recommended)
 
 Add the following entries to your Gradle build at the correct locations:
 
@@ -30,19 +33,38 @@ Add the API as dependency to your ``plugin.yml``:
 depend: [NBTAPI]
 ```
 
-# Option 2) Shading the NBT-API into your plugin
+Or, if you are using ``paper-plugin.yml``:
 
-To include NBT-API directly in your plugin, you can use the gradle shadow plugin.
+```yml
+dependencies:
+  server:
+    NBTAPI:
+      load: BEFORE
+      required: true
+      join-classpath: true
+```
+
+# Option 2) Shading the NBT-API into your plugin (Not recommended)
+
+> [!WARNING]
+> Due to the increasing amount of pitfalls in modern Paper, shading is not recommended. Please test with the normal plugin dependency before reporting issues.
+
+To include NBT-API directly in your plugin, you can use the [Gradle Shadow Plugin](https://gradleup.com/shadow/).
+
+Create an empty ``.mojang-mapped`` file in the META-INF folder of your plugin for 1.20+ Paper support.
+
+> [!WARNING]
+> Not adding this flag will make the shaded api not work on the latest Paper. It might also break other reflections/nms logic!
 
 Add the plugin to the build configuration, as shown here:
 
 ```groovy
 plugins {
-    id("com.github.johnrengelman.shadow") version "VERSION"
+    id("com.gradleup.shadow") version "VERSION"
 }
 ```
 
-The latest version of the shadow plugin can be found [here](https://github.com/johnrengelman/shadow/releases).
+The latest version of the shadow plugin can be found [here](https://plugins.gradle.org/plugin/com.gradleup.shadow).
 
 Add NBT-API to your dependencies:
 

wiki/Using-Maven.md

@@ -2,8 +2,11 @@ To start using NB-API, you either need to depend on its plugin version, or shade
 
 > [!IMPORTANT]
 > Plugin and shaded versions have different ``artifactId``. Make sure to correctly choose the one you need!
+>
+> [!IMPORTANT]
+> Alternative ways of loading the api like Libby are not supported on Discord/Github issues.
 
-# Option 1) NBT-API as a dependency
+# Option 1) NBT-API as a dependency (recommended)
 
 Add the following entries to your pom at the correct locations:
 
@@ -37,10 +40,29 @@ Add the API as dependency to your ``plugin.yml``:
 depend: [NBTAPI]
 ```
 
-# Option 2) Shading the NBT-API into your plugin
+Or, if you are using ``paper-plugin.yml``:
+
+```yml
+dependencies:
+  server:
+    NBTAPI:
+      load: BEFORE
+      required: true
+      join-classpath: true
+```
+
+# Option 2) Shading the NBT-API into your plugin (Not recommended)
+
+> [!WARNING]
+> Due to the increasing amount of pitfalls in modern Paper, shading is not recommended. Please test with the normal plugin dependency before reporting issues.
 
 To include NBT-API directly in your plugin, you can use the maven shade plugin.
 
+Create an empty ``.mojang-mapped`` file in the META-INF folder of your plugin for 1.20+ Paper support.
+
+> [!WARNING]
+> Not adding this flag will make the shaded api not work on the latest Paper. It might also break other reflections/nms logic!
+
 Add the plugin to the build configuration, as shown here:
 
 ```xml

wiki/Using-the-NBT-API.md

@@ -2,7 +2,7 @@
 
 ### Basics overview
 
-Most of the things are exposed inside the [NBT](https://tr7zw.github.io/Item-NBT-API/v2-api/de/tr7zw/changeme/nbtapi/NBT.html) class. Make sure to explore the Javadoc, or ask your IDE for suggestions!
+Most of the things are exposed inside the [NBT](https://tr7zw.github.io/Item-NBT-API/v2-api/de/tr7zw/changeme/nbtapi/NBT.html) class. Your specific use-case might not yet be covered by the wiki, so make sure to explore the [Javadoc](https://tr7zw.github.io/Item-NBT-API/v2-api/), or ask your IDE for suggestions!
 
 #### Basic getting and setting of data
 
@@ -43,14 +43,34 @@ nbt.getOrCreateCompound("subtag"); // Get or create a subtag
 #### Converting NBT to String and the String back to NBT
 
 ```java
-// Parse Mojang-Json string to nbt
+// Parse SNBT to nbt
 ReadWriteNBT nbt = NBT.parseNBT("{Health:20.0f,Motion:[0.0d,10.0d,0.0d],Silent:1b}");
-// Get the NBT back as a Mojang-Json string (works with any NBT object)
-String json = nbt.toString();
+// Get the NBT back as a SNBT (works with any NBT object)
+String snbt = nbt.toString();
 // Turn back into nbt again
-ReadWriteNBT nbt2 = NBT.parseNBT(json);
+ReadWriteNBT nbt2 = NBT.parseNBT(snbt);
 ```
 
+#### Comparing NBT data
+
+As with other objects in Java, you may compare nbt using `equals`.
+
+To see what exactly mismatched, you can use `ReadableNBT#extractDifference`:
+
+```java
+ReadWriteNBT nbt1 = NBT.parseNBT("{intTag:1,compoundTag:{floatTag:20.0f,booleanTag:1b}},intArray:[I;1,2]");
+ReadWriteNBT nbt2 = NBT.parseNBT("{intTag:1,compoundTag:{floatTag:20.0f,booleanTag:0b}},intArray:[I;1,2,3],alsoIntTag:2");
+
+ReadWriteNBT diff1 = nbt1.extractDifference(nbt2);
+ReadWriteNBT diff2 = nbt2.extractDifference(nbt1);
+```
+
+For the example above, `ReadableNBT#toString` will produce:
+
+diff1: `{compoundTag:{booleanTag:1b},intArray:[I;1,2]}`
+
+diff2: `{compoundTag:{booleanTag:0b},intArray:[I;1,2,3],alsoIntTag:2}`
+
 #### Merging Compounds
 
 You can "merge" the data from any given Compound onto some other Compound. This will overwrite the tags with the same name.
@@ -115,9 +135,13 @@ nbt.resolveOrDefault("list_key[-1]", "fallback_value"); // Get the last value in
 
 
 // NBT compound lists
+// Get the list (will create it if needed)
 ReadWriteNBTCompoundList nbtList = nbt.getOrCreateCompound("foo").getCompoundList("other_key");
-ReadWriteNBT nbtListEntry = addCompound();
+// Add new compound to the list
+ReadWriteNBT nbtListEntry = nbtList.addCompound();
 nbtListEntry.setBoolean("bar", true);
+// Add existing nbt compound to the list
+ReadWriteNBT otherNbtListEntry = nbtList.addCompound(NBT.parseNBT("{foo_bar:1b}"));
 
 // You can fetch compounds in lists
 nbt.resolveCompound("foo.other_key[0]"); // Get the first compound in list, or null
@@ -162,12 +186,33 @@ int someValue = NBT.modify(itemStack, nbt -> {
 
 > [!WARNING]
 > Never mix the usage of ItemMeta and NBT.
+> Setting ItemMeta will override any changes made to item's nbt.
+
+```java
+// WRONG, do not do this!
+ItemMeta meta = itemStack.getItemMeta();
+meta.setDisplayName("Modified!");
+NBT.modify(itemStack, nbt -> nbt.setBoolean("modified", true));
+itemStack.setItemMeta(meta); // Will undo all changes to nbt!
+
+
+// Correct, both ItemMeta and NBT will be applied
+NBT.modify(itemStack, nbt -> nbt.setBoolean("modified", true));
+// Taking ItemMeta snapshot after changes to nbt
+ItemMeta meta = itemStack.getItemMeta();
+meta.setDisplayName("Modified!");
+itemStack.setItemMeta(meta);
+// If making any further changes with NBT & ItemMeta,
+// re-take the item's ItemMeta after changing the nbt!
+```
+
+Alternatively, you may safely modify ItemMeta inside the NBT scope:
 
 ```java
 // Updating ItemMeta using NBT
 NBT.modify(itemStack, nbt -> {
     nbt.setInteger("kills", nbt.getOrDefault("kills", 0) + 1);
-    nbt.modifyMeta((meta, readOnlyNbt) -> { // Do not modify the nbt while modifying the meta!
+    nbt.modifyMeta((readOnlyNbt, meta) -> { // Do not modify the nbt while modifying the meta!
         meta.setDisplayName("Kills: " + readOnlyNbt.getOrDefault("kills", 0));
     });
     // Do more stuff
@@ -184,6 +229,15 @@ NBT.modify(itemStack, nbt -> {
 
 ```java
 // NOTE: This code is only for 1.20.5+!
+
+// Only reading vanilla data
+NBT.getComponents(item, nbt -> {
+    if (nbt.hasTag("minecraft:custom_name")) {
+        String customName = nbt.getString("minecraft:custom_name");
+    }
+});
+
+// Modifying vanilla data
 NBT.modifyComponents(item, nbt -> {
     nbt.setString("minecraft:custom_name", "{\"extra\":[\"foobar\"],\"text\":\"\"}");
 });
@@ -209,7 +263,12 @@ NBT.modify(entity, nbt -> {
 
 #### Accessing custom data
 
-For reading/storing custom data on (block-)entities, you should use methods that end with PersistentData.
+> [!WARNING]
+> Persistent data storage for custom (block-)entity nbt is only available in 1.14+.
+>
+> If you need to support versions below that, for entities you may use a workaround like storing data inside an item's nbt that the entity is wearing (e.g. having a button in mob's helmet, and storing data on that button).
+
+For reading/storing custom data on (block-)entities, you should use methods that end with ``PersistentData``.
 
 > [!IMPORTANT]
 > When working with block entities, make sure that the block entity exists in the world.
@@ -247,20 +306,26 @@ You can store data in block entities (block entities like chest, furnace, etc.)
 
 Thus, you have to use your own block data storage to store custom block data.
 
-You can store data inside Chunks since 1.16.4, and NBT-API allows you to do so by using ``NBTChunk``:
+You can store data inside Chunks using their PDC (Persistent Data Container) since Minecraft **1.16.4**. The NBT‑API provides read and modify methods in the `NBT` class to interact with it:
 
 ```java
-ReadWriteNBT nbt = new NBTChunk(chunk).getPersistentDataContainer();
+// Read the entire PDC or a specific value
+NBT.readChunkPDC(chunk, nbt -> { /* ... */ });
+String str = NBT.readAndGetChunkPDC(chunk, nbt -> nbt.getOrNull("key", String.class));
 ```
 
-Similarly, there is ``NBTBlock``, which allows you to store block data inside chunk's data.
+For convenience, you can also pass Blocks into `NBT#read/modify[AndGet]ChunkPDC` methods to store block data inside Chunk's PDC.
+Blocks are stored inside their chunk's PDC under a `blocks` compound, using the block's location (`X_Y_Z`) as the key for a subcompound.
 
 ```java
-// Block's data will be stored in Chunk's data in "blocks.x_y_z" subtag
-ReadWriteNBT nbt = new NBTBlock(block).getData();
+// Modify and retrieve data for a specific block
+boolean bool = NBT.modifyAndGetChunkPDC(block, nbt -> {
+    nbt.setString("owner_name", "Player123");
+    return nbt.getOrDefault("key", false);
+});
 ```
 
-**However**, keep in mind that this data is linked only to the location, and if the block gets broken/changed/exploded/moved/etc., the data will still be on that location unless manually cleared/moved!
+**However**, keep in mind that the block's data is linked only to the location, and if the block gets broken/changed/exploded/moved/etc., the data will still be on that location unless manually cleared/moved!
 
 Moreover, since the data is stored inside a Chunk, this will increase the chunk's size on the disk.
 
@@ -271,26 +336,32 @@ Moreover, since the data is stored inside a Chunk, this will increase the chunk'
 
 ### NBT files
 
-```java
-// Creating nbt file
-// NBTFile will automatically create the file if it does not exist
-NBTFile file = new NBTFile(new File("directory"), "test.nbt"); // Will be created at ./directory/test.nbt
-// Setting data 
-file.setString("foo", "bar");
-// Saving file
-file.save();
+NBTFileHandle allows working with nbt files.
 
-// Alternatively, you may use helper methods in NBTFile class
-// To read the file without creating it if does not exist:
-ReadWriteNBT nbt = NBTFile.readFrom(file);
-// To save nbt to the file:
-NBTFile.saveTo(file, nbt);
+```java
+// Will automatically create the file if it does not exist
+NBTFileHandle nbtFile = NBT.getFileHandle(new File("directory", "test.nbt"));
+// Setting data 
+nbtFile.setString("foo", "bar");
+// Saving the file after applying changes
+nbtFile.save();
+```
+
+Alternatively, you may read the nbt file without maintaining the link to it.
+Unlike NBTFileHandle, the file won't be automatically created if it does not exist.
+
+```java
+File file = new File("directory", "test.nbt");
+// Reading data from file (will return an empty compound if the file does not exist)
+ReadWriteNBT nbt = NBT.readFile(file);
+// Saving nbt to file
+NBT.writeFile(file, nbt);
 ```
 
 ### Converting Minecraft Objects to NBT and Strings
 
 The basic idea is that you can convert data into different representations:
-Minecraft Objects <-> NBT <-> String (Mojang-Json)
+Minecraft Objects <-> NBT <-> String (SNBT)
 
 #### Items
 
@@ -318,8 +389,8 @@ ReadWriteNBT nbt = NBT.itemStackArrayToNBT(itemStacks);
 ItemStack itemStack = NBT.itemStackFromNBT(nbt);
 ItemStack[] itemStacks = NBT.itemStackArrayFromNBT(nbt);
 // Reminder (NBT <-> String)
-String json = nbt.toString();
-ReadWriteNBT nbt = NBT.parseNBT(json);
+String snbt = nbt.toString();
+ReadWriteNBT nbt = NBT.parseNBT(snbt);
 ```
 
 #### Entities and block entities