Merge remote-tracking branch 'origin/master' into feature/1.21

.editorconfig

@@ -0,0 +1,14 @@
+root = true
+
+[*]
+charset = utf-8
+indent_size = 4
+indent_style = space
+insert_final_newline = true
+tab_width = 4
+max_line_length = off
+
+[*.java]
+ij_java_class_count_to_use_import_on_demand = 9999
+ij_java_doc_align_exception_comments = false
+ij_java_doc_align_param_comments = false

Jenkinsfile

@@ -20,7 +20,7 @@ pipeline {
 
             steps {
                 sh './gradlew javadoc'
-                step([$class: 'JavadocArchiver', javadocDir: 'build/docs/javadoc', keepAll: false])
+                step([$class: 'JavadocArchiver', javadocDir: 'protocol/build/docs/javadoc', keepAll: false])
             }
         }
     }

README.md

@@ -85,7 +85,7 @@ You can find the Javadocs for MCProtocolLib [on opencollab](https://ci.opencolla
 
 ## Building the Source
 
-MCProtocolLib uses Maven to manage dependencies. To build the source code, run `mvn clean install` in the project root directory.
+MCProtocolLib uses Gradle to manage dependencies. To build the source code, run `./gradlew clean build` in the project root directory.
 
 ## Support and Development
 
@@ -93,4 +93,4 @@ Please join [the GeyserMC Discord server](https://discord.gg/geysermc) and visit
 
 ## License
 
-MCProtocolLib is licensed under the **[MIT license](https://opensource.org/license/mit/)**.
+MCProtocolLib is licensed under the **[MIT license](https://opensource.org/license/mit)**.

gradle/libs.versions.toml

@@ -4,7 +4,7 @@ metadata.format.version = "1.1"
 
 adventure = "4.15.0"
 cloudburstnbt = "3.0.0.Final"
-mcauthlib = "6621fd0"
+mcauthlib = "e5b0bcc"
 math = "2.0"
 fastutil-maps = "8.5.3"
 netty = "4.1.103.Final"

protocol/src/main/java/org/geysermc/mcprotocollib/protocol/ClientListener.java

@@ -45,7 +45,7 @@ import org.geysermc.mcprotocollib.protocol.packet.status.serverbound.Serverbound
 import javax.crypto.KeyGenerator;
 import javax.crypto.SecretKey;
 import java.security.NoSuchAlgorithmException;
-import java.util.ArrayList;
+import java.util.Collections;
 
 /**
  * Handles making initial login and status requests for clients.
@@ -127,17 +127,22 @@ public class ClientListener extends SessionAdapter {
             } else if (packet instanceof ClientboundStartConfigurationPacket) {
                 session.send(new ServerboundConfigurationAcknowledgedPacket());
             } else if (packet instanceof ClientboundTransferPacket transferPacket) {
+                if (session.getFlag(MinecraftConstants.FOLLOW_TRANSFERS, true)) {
                     TcpClientSession newSession = new TcpClientSession(transferPacket.getHost(), transferPacket.getPort(), session.getPacketProtocol());
                     newSession.setFlags(session.getFlags());
                     session.disconnect("Transferring");
                     newSession.connect(true, true);
                 }
+            }
         } else if (protocol.getState() == ProtocolState.CONFIGURATION) {
             if (packet instanceof ClientboundFinishConfigurationPacket) {
                 session.send(new ServerboundFinishConfigurationPacket());
             } else if (packet instanceof ClientboundSelectKnownPacks) {
-                session.send(new ServerboundSelectKnownPacks(new ArrayList<>()));
+                if (session.getFlag(MinecraftConstants.SEND_BLANK_KNOWN_PACKS_RESPONSE, true)) {
+                    session.send(new ServerboundSelectKnownPacks(Collections.emptyList()));
+                }
             } else if (packet instanceof ClientboundTransferPacket transferPacket) {
+                if (session.getFlag(MinecraftConstants.FOLLOW_TRANSFERS, true)) {
                     TcpClientSession newSession = new TcpClientSession(transferPacket.getHost(), transferPacket.getPort(), session.getPacketProtocol());
                     newSession.setFlags(session.getFlags());
                     session.disconnect("Transferring");
@@ -145,6 +150,7 @@ public class ClientListener extends SessionAdapter {
                 }
             }
         }
+    }
 
     @Override
     public void packetSent(Session session, Packet packet) {

protocol/src/main/java/org/geysermc/mcprotocollib/protocol/MinecraftConstants.java

@@ -50,6 +50,16 @@ public final class MinecraftConstants {
      */
     public static final Flag<ServerPingTimeHandler> SERVER_PING_TIME_HANDLER_KEY = new Flag<>("server-ping-time-handler", ServerPingTimeHandler.class);
 
+    /**
+     * Session flag for determining if an automatic response should be sent to the ClientboundSelectKnownPacks.
+     */
+    public static final Flag<Boolean> SEND_BLANK_KNOWN_PACKS_RESPONSE = new Flag<>("send-blank-known-packs-response", Boolean.class);
+
+    /**
+     * Session flag for determining whether to create a new TcpClientSession when the Java server sends a ClientboundTransferPacket.
+     */
+    public static final Flag<Boolean> FOLLOW_TRANSFERS = new Flag<>("follow-transfers", Boolean.class);
+
     // Server Key Constants
 
     /**

protocol/src/main/java/org/geysermc/mcprotocollib/protocol/codec/MinecraftCodecHelper.java

@@ -130,6 +130,23 @@ public class MinecraftCodecHelper extends BasePacketCodecHelper {
         }
     }
 
+    public <T> List<T> readList(ByteBuf buf, Function<ByteBuf, T> reader) {
+        int size = this.readVarInt(buf);
+        List<T> list = new ArrayList<>(size);
+        for (int i = 0; i < size; i++) {
+            list.add(reader.apply(buf));
+        }
+
+        return list;
+    }
+
+    public <T> void writeList(ByteBuf buf, List<T> value, BiConsumer<ByteBuf, T> writer) {
+        this.writeVarInt(buf, value.size());
+        for (T t : value) {
+            writer.accept(buf, t);
+        }
+    }
+
     public <T> Holder<T> readHolder(ByteBuf buf, Function<ByteBuf, T> readCustom) {
         int registryId = this.readVarInt(buf);
         return registryId == 0 ? Holder.ofCustom(readCustom.apply(buf)) : Holder.ofId(registryId - 1);
@@ -252,7 +269,7 @@ public class MinecraftCodecHelper extends BasePacketCodecHelper {
 
             NbtType<?> type = NbtType.byId(typeId);
 
-            return new NBTInputStream(input).readValue(type);
+            return new NBTInputStream(input).readValue(type, 512);
         } catch (IOException e) {
             throw new IllegalArgumentException(e);
         }
@@ -270,7 +287,7 @@ public class MinecraftCodecHelper extends BasePacketCodecHelper {
             NbtType<?> type = NbtType.byClass(tag.getClass());
             output.writeByte(type.getId());
 
-            new NBTOutputStream(output).writeValue(tag);
+            new NBTOutputStream(output).writeValue(tag, 512);
         } catch (IOException e) {
             throw new IllegalArgumentException(e);
         }

protocol/src/main/java/org/geysermc/mcprotocollib/protocol/data/game/entity/Effect.java

@@ -33,7 +33,13 @@ public enum Effect {
     DOLPHINS_GRACE,
     BAD_OMEN,
     HERO_OF_THE_VILLAGE,
-    DARKNESS;
+    DARKNESS,
+    TRIAL_OMEN,
+    RAID_OMEN,
+    WIND_CHARGED,
+    WEAVING,
+    OOZING,
+    INFESTED;
 
     public static final Effect[] VALUES = values();
 

protocol/src/main/java/org/geysermc/mcprotocollib/protocol/data/game/item/component/AdventureModePredicate.java

@@ -16,8 +16,7 @@ public class AdventureModePredicate {
     @Data
     @AllArgsConstructor
     public static class BlockPredicate {
-        private final @Nullable String location;
+        private final @Nullable HolderSet blocks;
-        private final int @Nullable [] holders;
         private final @Nullable List<PropertyMatcher> properties;
         private final @Nullable NbtMap nbt;
     }

protocol/src/main/java/org/geysermc/mcprotocollib/protocol/data/game/item/component/FoodProperties.java

@@ -17,7 +17,7 @@ public class FoodProperties {
     @Data
     @AllArgsConstructor
     public static class PossibleEffect {
-        private final MobEffectDetails effect;
+        private final MobEffectInstance effect;
         private final float probability;
     }
 }

protocol/src/main/java/org/geysermc/mcprotocollib/protocol/data/game/item/component/HolderSet.java

@@ -0,0 +1,41 @@
+package org.geysermc.mcprotocollib.protocol.data.game.item.component;
+
+import lombok.Data;
+import lombok.NonNull;
+import org.checkerframework.checker.nullness.qual.Nullable;
+
+import java.util.function.Function;
+
+/**
+ * Represents a set of holders that could either be explicit, or resolved from a tag location.
+ * The client has to know how to resolve the tag location to get the holders.
+ */
+@Data
+public final class HolderSet {
+    private final @Nullable String location;
+    private final int @Nullable [] holders;
+
+    public HolderSet(int @NonNull [] holders) {
+        this.location = null;
+        this.holders = holders;
+    }
+
+    public HolderSet(@NonNull String location) {
+        this.location = location;
+        this.holders = null;
+    }
+
+    /**
+     * Return either the explicit holders, or resolve the tag location to get the holders.
+     *
+     * @param tagResolver The function to resolve the tag location to get the holders.
+     * @return The holders.
+     */
+    public int[] resolve(Function<String, int[]> tagResolver) {
+        if (holders != null) {
+            return holders;
+        }
+
+        return tagResolver.apply(location);
+    }
+}

protocol/src/main/java/org/geysermc/mcprotocollib/protocol/data/game/item/component/ItemCodecHelper.java

@@ -10,6 +10,7 @@ import org.cloudburstmc.nbt.NbtList;
 import org.cloudburstmc.nbt.NbtType;
 import org.geysermc.mcprotocollib.protocol.codec.MinecraftCodecHelper;
 import org.geysermc.mcprotocollib.protocol.data.game.Holder;
+import org.geysermc.mcprotocollib.protocol.data.game.entity.Effect;
 import org.geysermc.mcprotocollib.protocol.data.game.entity.attribute.ModifierOperation;
 import org.geysermc.mcprotocollib.protocol.data.game.level.sound.BuiltinSound;
 import org.geysermc.mcprotocollib.protocol.data.game.level.sound.CustomSound;
@@ -34,21 +35,13 @@ public class ItemCodecHelper extends MinecraftCodecHelper {
 
     public <T> Filterable<T> readFilterable(ByteBuf buf, Function<ByteBuf, T> reader) {
         T raw = reader.apply(buf);
-        T filtered = null;
+        T filtered = this.readNullable(buf, reader);
-        if (buf.readBoolean()) {
-            filtered = reader.apply(buf);
-        }
         return new Filterable<>(raw, filtered);
     }
 
     public <T> void writeFilterable(ByteBuf buf, Filterable<T> filterable, BiConsumer<ByteBuf, T> writer) {
         writer.accept(buf, filterable.getRaw());
-        if (filterable.getOptional() != null) {
+        this.writeNullable(buf, filterable.getOptional(), writer);
-            buf.writeBoolean(true);
-            writer.accept(buf, filterable.getOptional());
-        } else {
-            buf.writeBoolean(false);
-        }
     }
 
     public ItemEnchantments readItemEnchantments(ByteBuf buf) {
@@ -72,12 +65,7 @@ public class ItemCodecHelper extends MinecraftCodecHelper {
     }
 
     public AdventureModePredicate readAdventureModePredicate(ByteBuf buf) {
-        List<AdventureModePredicate.BlockPredicate> predicates = new ArrayList<>();
+        List<AdventureModePredicate.BlockPredicate> predicates = this.readList(buf, this::readBlockPredicate);
-        int predicateCount = this.readVarInt(buf);
-        for (int i = 0; i < predicateCount; i++) {
-            predicates.add(this.readBlockPredicate(buf));
-        }
-
         return new AdventureModePredicate(predicates, buf.readBoolean());
     }
 
@@ -91,59 +79,29 @@ public class ItemCodecHelper extends MinecraftCodecHelper {
     }
 
     public AdventureModePredicate.BlockPredicate readBlockPredicate(ByteBuf buf) {
-        String location = null;
+        HolderSet holderSet = this.readNullable(buf, this::readHolderSet);
-        int[] holders = null;
+        List<AdventureModePredicate.PropertyMatcher> propertyMatchers = this.readNullable(buf, (input) -> {
-        List<AdventureModePredicate.PropertyMatcher> propertyMatchers = null;
+            List<AdventureModePredicate.PropertyMatcher> matchers = new ArrayList<>();
-
+            int matcherCount = this.readVarInt(input);
-        if (buf.readBoolean()) {
-            int length = this.readVarInt(buf) - 1;
-            if (length == -1) {
-                location = this.readResourceLocation(buf);
-            } else {
-                holders = new int[length];
-                for (int i = 0; i < length; i++) {
-                    holders[i] = this.readVarInt(buf);
-                }
-            }
-        }
-
-        if (buf.readBoolean()) {
-            propertyMatchers = new ArrayList<>();
-            int matcherCount = this.readVarInt(buf);
             for (int i = 0; i < matcherCount; i++) {
-                String name = this.readString(buf);
+                String name = this.readString(input);
-                if (buf.readBoolean()) {
+                if (input.readBoolean()) {
-                    propertyMatchers.add(new AdventureModePredicate.PropertyMatcher(name, this.readString(buf), null, null));
+                    matchers.add(new AdventureModePredicate.PropertyMatcher(name, this.readString(input), null, null));
                 } else {
-                    propertyMatchers.add(new AdventureModePredicate.PropertyMatcher(name, null, this.readString(buf), this.readString(buf)));
+                    matchers.add(new AdventureModePredicate.PropertyMatcher(name, null, this.readString(input), this.readString(input)));
-                }
                 }
             }
+            return matchers;
+        });
 
-        return new AdventureModePredicate.BlockPredicate(location, holders, propertyMatchers, this.readNullable(buf, this::readCompoundTag));
+        return new AdventureModePredicate.BlockPredicate(holderSet, propertyMatchers, this.readNullable(buf, this::readCompoundTag));
     }
 
     public void writeBlockPredicate(ByteBuf buf, AdventureModePredicate.BlockPredicate blockPredicate) {
-        if (blockPredicate.getLocation() == null && blockPredicate.getHolders() == null) {
+        this.writeNullable(buf, blockPredicate.getBlocks(), this::writeHolderSet);
-            buf.writeBoolean(false);
+        this.writeNullable(buf, blockPredicate.getProperties(), (output, properties) -> {
-        } else {
             buf.writeBoolean(true);
-            if (blockPredicate.getLocation() != null) {
+            for (AdventureModePredicate.PropertyMatcher matcher : properties) {
-                this.writeVarInt(buf, 0);
-                this.writeResourceLocation(buf, blockPredicate.getLocation());
-            } else {
-                this.writeVarInt(buf, blockPredicate.getHolders().length + 1);
-                for (int holder : blockPredicate.getHolders()) {
-                    this.writeVarInt(buf, holder);
-                }
-            }
-        }
-
-        if (blockPredicate.getProperties() == null) {
-            buf.writeBoolean(false);
-        } else {
-            buf.writeBoolean(true);
-            for (AdventureModePredicate.PropertyMatcher matcher : blockPredicate.getProperties()) {
                 this.writeString(buf, matcher.getName());
                 if (matcher.getValue() != null) {
                     buf.writeBoolean(true);
@@ -154,32 +112,46 @@ public class ItemCodecHelper extends MinecraftCodecHelper {
                     this.writeString(buf, matcher.getMaxValue());
                 }
             }
-        }
+        });
 
         this.writeNullable(buf, blockPredicate.getNbt(), this::writeAnyTag);
     }
 
-    public ToolData readToolData(ByteBuf buf) {
+    public HolderSet readHolderSet(ByteBuf buf) {
-        List<ToolData.Rule> rules = new ArrayList<>();
-        int ruleCount = this.readVarInt(buf);
-        for (int i = 0; i < ruleCount; i++) {
-            String location = null;
-            int[] holders = null;
-
         int length = this.readVarInt(buf) - 1;
         if (length == -1) {
-                location = this.readResourceLocation(buf);
+            return new HolderSet(this.readResourceLocation(buf));
         } else {
-                holders = new int[length];
+            int[] holders = new int[length];
-                for (int j = 0; j < length; j++) {
+            for (int i = 0; i < length; i++) {
-                    holders[j] = this.readVarInt(buf);
+                holders[i] = this.readVarInt(buf);
+            }
+
+            return new HolderSet(holders);
         }
     }
 
-            Float speed = this.readNullable(buf, ByteBuf::readFloat);
+    public void writeHolderSet(ByteBuf buf, HolderSet holderSet) {
-            Boolean correctForDrops = this.readNullable(buf, ByteBuf::readBoolean);
+        if (holderSet.getLocation() != null) {
-            rules.add(new ToolData.Rule(location, holders, speed, correctForDrops));
+            this.writeVarInt(buf, 0);
+            this.writeResourceLocation(buf, holderSet.getLocation());
+        } else {
+            assert holderSet.getHolders() != null;
+            this.writeVarInt(buf, holderSet.getHolders().length + 1);
+            for (int holder : holderSet.getHolders()) {
+                this.writeVarInt(buf, holder);
             }
+        }
+    }
+
+    public ToolData readToolData(ByteBuf buf) {
+        List<ToolData.Rule> rules = this.readList(buf, (input) -> {
+            HolderSet holderSet = this.readHolderSet(input);
+
+            Float speed = this.readNullable(input, ByteBuf::readFloat);
+            Boolean correctForDrops = this.readNullable(input, ByteBuf::readBoolean);
+            return new ToolData.Rule(holderSet, speed, correctForDrops);
+        });
 
         float defaultMiningSpeed = buf.readFloat();
         int damagePerBlock = this.readVarInt(buf);
@@ -187,57 +159,42 @@ public class ItemCodecHelper extends MinecraftCodecHelper {
     }
 
     public void writeToolData(ByteBuf buf, ToolData data) {
-        this.writeVarInt(buf, data.getRules().size());
+        this.writeList(buf, data.getRules(), (output, rule) -> {
-        for (ToolData.Rule rule : data.getRules()) {
+            this.writeHolderSet(output, rule.getBlocks());
-            if (rule.getLocation() != null) {
+            this.writeNullable(output, rule.getSpeed(), ByteBuf::writeFloat);
-                this.writeVarInt(buf, 0);
+            this.writeNullable(output, rule.getCorrectForDrops(), ByteBuf::writeBoolean);
-                this.writeResourceLocation(buf, rule.getLocation());
+        });
-            } else {
-                this.writeVarInt(buf, rule.getHolders().length + 1);
-                for (int holder : rule.getHolders()) {
-                    this.writeVarInt(buf, holder);
-                }
-            }
-
-            this.writeNullable(buf, rule.getSpeed(), ByteBuf::writeFloat);
-            this.writeNullable(buf, rule.getCorrectForDrops(), ByteBuf::writeBoolean);
-        }
 
         buf.writeFloat(data.getDefaultMiningSpeed());
         this.writeVarInt(buf, data.getDamagePerBlock());
     }
 
     public ItemAttributeModifiers readItemAttributeModifiers(ByteBuf buf) {
-        List<ItemAttributeModifiers.Entry> modifiers = new ArrayList<>();
+        List<ItemAttributeModifiers.Entry> modifiers = this.readList(buf, (input) -> {
-        int modifierCount = this.readVarInt(buf);
+            int attribute = this.readVarInt(input);
-        for (int i = 0; i < modifierCount; i++) {
-            int attribute = this.readVarInt(buf);
 
-            UUID id = this.readUUID(buf);
+            UUID id = this.readUUID(input);
-            String name = this.readString(buf);
+            String name = this.readString(input);
-            double amount = buf.readDouble();
+            double amount = input.readDouble();
-            ModifierOperation operation = ModifierOperation.from(this.readVarInt(buf));
+            ModifierOperation operation = ModifierOperation.from(this.readVarInt(input));
             ItemAttributeModifiers.AttributeModifier modifier = new ItemAttributeModifiers.AttributeModifier(id, name, amount, operation);
 
-            ItemAttributeModifiers.EquipmentSlotGroup slot = ItemAttributeModifiers.EquipmentSlotGroup.from(this.readVarInt(buf));
+            ItemAttributeModifiers.EquipmentSlotGroup slot = ItemAttributeModifiers.EquipmentSlotGroup.from(this.readVarInt(input));
-            modifiers.add(new ItemAttributeModifiers.Entry(attribute, modifier, slot));
+            return new ItemAttributeModifiers.Entry(attribute, modifier, slot);
-        }
+        });
 
         return new ItemAttributeModifiers(modifiers, buf.readBoolean());
     }
 
     public void writeItemAttributeModifiers(ByteBuf buf, ItemAttributeModifiers modifiers) {
-        this.writeVarInt(buf, modifiers.getModifiers().size());
+        this.writeList(buf, modifiers.getModifiers(), (output, entry) -> {
-        for (ItemAttributeModifiers.Entry modifier : modifiers.getModifiers()) {
+            this.writeVarInt(output, entry.getAttribute());
-            this.writeVarInt(buf, modifier.getAttribute());
+            this.writeUUID(output, entry.getModifier().getId());
-
+            this.writeString(output, entry.getModifier().getName());
-            this.writeUUID(buf, modifier.getModifier().getId());
+            output.writeDouble(entry.getModifier().getAmount());
-            this.writeString(buf, modifier.getModifier().getName());
+            this.writeVarInt(output, entry.getModifier().getOperation().ordinal());
-            buf.writeDouble(modifier.getModifier().getAmount());
+            this.writeVarInt(output, entry.getSlot().ordinal());
-            this.writeVarInt(buf, modifier.getModifier().getOperation().ordinal());
+        });
-
-            this.writeVarInt(buf, modifier.getSlot().ordinal());
-        }
 
         buf.writeBoolean(modifiers.isShowInTooltip());
     }
@@ -255,11 +212,7 @@ public class ItemCodecHelper extends MinecraftCodecHelper {
         int potionId = buf.readBoolean() ? this.readVarInt(buf) : -1;
         int customColor = buf.readBoolean() ? buf.readInt() : -1;
 
-        Int2ObjectMap<MobEffectDetails> customEffects = new Int2ObjectOpenHashMap<>();
+        List<MobEffectInstance> customEffects = this.readList(buf, this::readEffectInstance);
-        int effectCount = this.readVarInt(buf);
-        for (int i = 0; i < effectCount; i++) {
-            customEffects.put(this.readVarInt(buf), this.readEffectDetails(buf));
-        }
         return new PotionContents(potionId, customColor, customEffects);
     }
 
@@ -278,11 +231,7 @@ public class ItemCodecHelper extends MinecraftCodecHelper {
             buf.writeInt(contents.getCustomColor());
         }
 
-        this.writeVarInt(buf, contents.getCustomEffects().size());
+        this.writeList(buf, contents.getCustomEffects(), this::writeEffectInstance);
-        for (Int2ObjectMap.Entry<MobEffectDetails> entry : contents.getCustomEffects().int2ObjectEntrySet()) {
-            this.writeVarInt(buf, entry.getIntKey());
-            this.writeEffectDetails(buf, entry.getValue());
-        }
     }
 
     public FoodProperties readFoodProperties(ByteBuf buf) {
@@ -291,11 +240,11 @@ public class ItemCodecHelper extends MinecraftCodecHelper {
         boolean canAlwaysEat = buf.readBoolean();
         float eatSeconds = buf.readFloat();
 
-        List<FoodProperties.PossibleEffect> effects = new ArrayList<>();
+        List<FoodProperties.PossibleEffect> effects = this.readList(buf, (input) -> {
-        int effectCount = this.readVarInt(buf);
+            MobEffectInstance effect = this.readEffectInstance(input);
-        for (int i = 0; i < effectCount; i++) {
+            float probability = input.readFloat();
-            effects.add(new FoodProperties.PossibleEffect(this.readEffectDetails(buf), buf.readFloat()));
+            return new FoodProperties.PossibleEffect(effect, probability);
-        }
+        });
 
         return new FoodProperties(nutrition, saturationModifier, canAlwaysEat, eatSeconds, effects);
     }
@@ -306,11 +255,15 @@ public class ItemCodecHelper extends MinecraftCodecHelper {
         buf.writeBoolean(properties.isCanAlwaysEat());
         buf.writeFloat(properties.getEatSeconds());
 
-        this.writeVarInt(buf, properties.getEffects().size());
+        this.writeList(buf, properties.getEffects(), (output, effect) -> {
-        for (FoodProperties.PossibleEffect effect : properties.getEffects()) {
+            this.writeEffectInstance(output, effect.getEffect());
-            this.writeEffectDetails(buf, effect.getEffect());
+            output.writeFloat(effect.getProbability());
-            buf.writeFloat(effect.getProbability());
+        });
     }
+
+    public MobEffectInstance readEffectInstance(ByteBuf buf) {
+        Effect effect = this.readEffect(buf);
+        return new MobEffectInstance(effect, this.readEffectDetails(buf));
     }
 
     public MobEffectDetails readEffectDetails(ByteBuf buf) {
@@ -323,6 +276,11 @@ public class ItemCodecHelper extends MinecraftCodecHelper {
         return new MobEffectDetails(amplifier, duration, ambient, showParticles, showIcon, hiddenEffect);
     }
 
+    public void writeEffectInstance(ByteBuf buf, MobEffectInstance instance) {
+        this.writeEffect(buf, instance.getEffect());
+        this.writeEffectDetails(buf, instance.getDetails());
+    }
+
     public void writeEffectDetails(ByteBuf buf, MobEffectDetails details) {
         this.writeVarInt(buf, details.getAmplifier());
         this.writeVarInt(buf, details.getDuration());
@@ -342,20 +300,12 @@ public class ItemCodecHelper extends MinecraftCodecHelper {
     }
 
     public WritableBookContent readWritableBookContent(ByteBuf buf) {
-        List<Filterable<String>> pages = new ArrayList<>();
+        List<Filterable<String>> pages = this.readList(buf, (input) -> this.readFilterable(input, this::readString));
-        int pageCount = this.readVarInt(buf);
-        for (int i = 0; i < pageCount; i++) {
-            pages.add(this.readFilterable(buf, this::readString));
-        }
-
         return new WritableBookContent(pages);
     }
 
     public void writeWritableBookContent(ByteBuf buf, WritableBookContent content) {
-        this.writeVarInt(buf, content.getPages().size());
+        this.writeList(buf, content.getPages(), (output, page) -> this.writeFilterable(output, page, this::writeString));
-        for (Filterable<String> page : content.getPages()) {
-            this.writeFilterable(buf, page, this::writeString);
-        }
     }
 
     public WrittenBookContent readWrittenBookContent(ByteBuf buf) {
@@ -363,12 +313,7 @@ public class ItemCodecHelper extends MinecraftCodecHelper {
         String author = this.readString(buf);
         int generation = this.readVarInt(buf);
 
-        List<Filterable<Component>> pages = new ArrayList<>();
+        List<Filterable<Component>> pages = this.readList(buf, (input) -> this.readFilterable(input, this::readComponent));
-        int pageCount = this.readVarInt(buf);
-        for (int i = 0; i < pageCount; i++) {
-            pages.add(this.readFilterable(buf, this::readComponent));
-        }
-
         boolean resolved = buf.readBoolean();
         return new WrittenBookContent(title, author, generation, pages, resolved);
     }
@@ -378,10 +323,7 @@ public class ItemCodecHelper extends MinecraftCodecHelper {
         this.writeString(buf, content.getAuthor());
         this.writeVarInt(buf, content.getGeneration());
 
-        this.writeVarInt(buf, content.getPages().size());
+        this.writeList(buf, content.getPages(), (output, page) -> this.writeFilterable(output, page, this::writeComponent));
-        for (Filterable<Component> page : content.getPages()) {
-            this.writeFilterable(buf, page, this::writeComponent);
-        }
 
         buf.writeBoolean(content.isResolved());
     }
@@ -544,11 +486,7 @@ public class ItemCodecHelper extends MinecraftCodecHelper {
         UUID id = this.readNullable(buf, this::readUUID);
         GameProfile profile = new GameProfile(id, name);
 
-        List<GameProfile.Property> properties = new ArrayList<>();
+        List<GameProfile.Property> properties = this.readList(buf, this::readProperty);
-        int propertyCount = this.readVarInt(buf);
-        for (int i = 0; i < propertyCount; i++) {
-            properties.add(this.readProperty(buf));
-        }
         profile.setProperties(properties);
 
         return profile;
@@ -558,10 +496,7 @@ public class ItemCodecHelper extends MinecraftCodecHelper {
         this.writeNullable(buf, profile.getName(), this::writeString);
         this.writeNullable(buf, profile.getId(), this::writeUUID);
 
-        this.writeVarInt(buf, profile.getProperties().size());
+        this.writeList(buf, profile.getProperties(), this::writeProperty);
-        for (GameProfile.Property property : profile.getProperties()) {
-            this.writeProperty(buf, property);
-        }
     }
 
     public BannerPatternLayer readBannerPatternLayer(ByteBuf buf) {

protocol/src/main/java/org/geysermc/mcprotocollib/protocol/data/game/item/component/MobEffectInstance.java

@@ -0,0 +1,13 @@
+package org.geysermc.mcprotocollib.protocol.data.game.item.component;
+
+import lombok.AllArgsConstructor;
+import lombok.Data;
+import lombok.NonNull;
+import org.geysermc.mcprotocollib.protocol.data.game.entity.Effect;
+
+@Data
+@AllArgsConstructor
+public class MobEffectInstance {
+    private final @NonNull Effect effect;
+    private final @NonNull MobEffectDetails details;
+}

protocol/src/main/java/org/geysermc/mcprotocollib/protocol/data/game/item/component/PotionContents.java

@@ -1,13 +1,14 @@
 package org.geysermc.mcprotocollib.protocol.data.game.item.component;
 
-import it.unimi.dsi.fastutil.ints.Int2ObjectMap;
 import lombok.AllArgsConstructor;
 import lombok.Data;
 
+import java.util.List;
+
 @Data
 @AllArgsConstructor
 public class PotionContents {
     private final int potionId;
     private final int customColor;
-    private final Int2ObjectMap<MobEffectDetails> customEffects;
+    private final List<MobEffectInstance> customEffects;
 }

protocol/src/main/java/org/geysermc/mcprotocollib/protocol/data/game/item/component/ToolData.java

@@ -2,6 +2,7 @@ package org.geysermc.mcprotocollib.protocol.data.game.item.component;
 
 import lombok.AllArgsConstructor;
 import lombok.Data;
+import lombok.NonNull;
 import org.jetbrains.annotations.Nullable;
 
 import java.util.List;
@@ -16,8 +17,7 @@ public class ToolData {
     @Data
     @AllArgsConstructor
     public static class Rule {
-        private final @Nullable String location;
+        private final @NonNull HolderSet blocks;
-        private final int @Nullable [] holders;
         private final @Nullable Float speed;
         private final @Nullable Boolean correctForDrops;
     }

protocol/src/main/java/org/geysermc/mcprotocollib/protocol/data/game/level/map/MapIconType.java

@@ -34,7 +34,8 @@ public enum MapIconType {
     SNOWY_VILLAGE,
     TAIGA_VILLAGE,
     JUNGLE_TEMPLE,
-    SWAMP_HUT;
+    SWAMP_HUT,
+    TRIAL_CHAMBERS;
 
     private static final MapIconType[] VALUES = values();
 

protocol/src/main/java/org/geysermc/mcprotocollib/protocol/packet/configuration/clientbound/ClientboundRegistryDataPacket.java

@@ -8,7 +8,6 @@ import org.geysermc.mcprotocollib.protocol.codec.MinecraftCodecHelper;
 import org.geysermc.mcprotocollib.protocol.codec.MinecraftPacket;
 import org.geysermc.mcprotocollib.protocol.data.game.RegistryEntry;
 
-import java.util.ArrayList;
 import java.util.List;
 
 @Data
@@ -20,22 +19,15 @@ public class ClientboundRegistryDataPacket implements MinecraftPacket {
 
     public ClientboundRegistryDataPacket(ByteBuf in, MinecraftCodecHelper helper) {
         this.registry = helper.readResourceLocation(in);
-        this.entries = new ArrayList<>();
+        this.entries = helper.readList(in, buf -> new RegistryEntry(helper.readResourceLocation(buf), helper.readNullable(buf, helper::readCompoundTag)));
-
-        int entryCount = helper.readVarInt(in);
-        for (int i = 0; i < entryCount; i++) {
-            this.entries.add(new RegistryEntry(helper.readResourceLocation(in), helper.readNullable(in, helper::readCompoundTag)));
-        }
     }
 
     @Override
     public void serialize(ByteBuf out, MinecraftCodecHelper helper) {
         helper.writeResourceLocation(out, this.registry);
-
+        helper.writeList(out, this.entries, (buf, entry) -> {
-        helper.writeVarInt(out, this.entries.size());
+            helper.writeResourceLocation(buf, entry.getId());
-        for (RegistryEntry entry : this.entries) {
+            helper.writeNullable(buf, entry.getData(), helper::writeAnyTag);
-            helper.writeResourceLocation(out, entry.getId());
+        });
-            helper.writeNullable(out, entry.getData(), helper::writeAnyTag);
-        }
     }
 }

protocol/src/main/java/org/geysermc/mcprotocollib/protocol/packet/configuration/clientbound/ClientboundSelectKnownPacks.java

@@ -8,7 +8,6 @@ import org.geysermc.mcprotocollib.protocol.codec.MinecraftCodecHelper;
 import org.geysermc.mcprotocollib.protocol.codec.MinecraftPacket;
 import org.geysermc.mcprotocollib.protocol.data.game.KnownPack;
 
-import java.util.ArrayList;
 import java.util.List;
 
 @Data
@@ -18,20 +17,15 @@ public class ClientboundSelectKnownPacks implements MinecraftPacket {
     private final List<KnownPack> knownPacks;
 
     public ClientboundSelectKnownPacks(ByteBuf in, MinecraftCodecHelper helper) {
-        this.knownPacks = new ArrayList<>();
+        this.knownPacks = helper.readList(in, buf -> new KnownPack(helper.readString(buf), helper.readString(buf), helper.readString(buf)));
-        int entryCount = helper.readVarInt(in);
-        for (int i = 0; i < entryCount; i++) {
-            this.knownPacks.add(new KnownPack(helper.readString(in), helper.readString(in), helper.readString(in)));
-        }
     }
 
     @Override
     public void serialize(ByteBuf out, MinecraftCodecHelper helper) {
-        helper.writeVarInt(out, this.knownPacks.size());
+        helper.writeList(out, this.knownPacks, (buf, entry) -> {
-        for (KnownPack entry : this.knownPacks) {
+            helper.writeString(buf, entry.getNamespace());
-            helper.writeString(out, entry.getNamespace());
+            helper.writeString(buf, entry.getId());
-            helper.writeString(out, entry.getId());
+            helper.writeString(buf, entry.getVersion());
-            helper.writeString(out, entry.getVersion());
+        });
-        }
     }
 }

protocol/src/main/java/org/geysermc/mcprotocollib/protocol/packet/ingame/clientbound/ClientboundPlayerChatPacket.java

@@ -39,12 +39,11 @@ public class ClientboundPlayerChatPacket implements MinecraftPacket {
     public ClientboundPlayerChatPacket(ByteBuf in, MinecraftCodecHelper helper) {
         this.sender = helper.readUUID(in);
         this.index = helper.readVarInt(in);
-        if (in.readBoolean()) {
+        this.messageSignature = helper.readNullable(in, buf -> {
-            this.messageSignature = new byte[256];
+            byte[] signature = new byte[256];
-            in.readBytes(this.messageSignature);
+            buf.readBytes(signature);
-        } else {
+            return signature;
-            this.messageSignature = null;
+        });
-        }
 
         this.content = helper.readString(in, 256);
         this.timeStamp = in.readLong();
@@ -67,10 +66,7 @@ public class ClientboundPlayerChatPacket implements MinecraftPacket {
     public void serialize(ByteBuf out, MinecraftCodecHelper helper) {
         helper.writeUUID(out, this.sender);
         helper.writeVarInt(out, this.index);
-        out.writeBoolean(this.messageSignature != null);
+        helper.writeNullable(out, this.messageSignature, ByteBuf::writeBytes);
-        if (this.messageSignature != null) {
-            out.writeBytes(this.messageSignature);
-        }
 
         helper.writeString(out, this.content);
         out.writeLong(this.timeStamp);

protocol/src/main/java/org/geysermc/mcprotocollib/protocol/packet/ingame/clientbound/ClientboundPlayerInfoRemovePacket.java

@@ -7,7 +7,6 @@ import lombok.With;
 import org.geysermc.mcprotocollib.protocol.codec.MinecraftCodecHelper;
 import org.geysermc.mcprotocollib.protocol.codec.MinecraftPacket;
 
-import java.util.ArrayList;
 import java.util.List;
 import java.util.UUID;
 
@@ -18,17 +17,10 @@ public class ClientboundPlayerInfoRemovePacket implements MinecraftPacket {
     private final List<UUID> profileIds;
 
     public ClientboundPlayerInfoRemovePacket(ByteBuf in, MinecraftCodecHelper helper) {
-        this.profileIds = new ArrayList<>();
+        this.profileIds = helper.readList(in, helper::readUUID);
-        int numIds = helper.readVarInt(in);
-        for (int i = 0; i < numIds; i++) {
-            this.profileIds.add(helper.readUUID(in));
-        }
     }
 
     public void serialize(ByteBuf out, MinecraftCodecHelper helper) {
-        helper.writeVarInt(out, this.profileIds.size());
+        helper.writeList(out, this.profileIds, helper::writeUUID);
-        for (UUID id : this.profileIds) {
-            helper.writeUUID(out, id);
-        }
     }
 }

protocol/src/main/java/org/geysermc/mcprotocollib/protocol/packet/ingame/clientbound/ClientboundPlayerInfoUpdatePacket.java

@@ -16,9 +16,7 @@ import java.security.GeneralSecurityException;
 import java.security.KeyFactory;
 import java.security.PublicKey;
 import java.security.spec.X509EncodedKeySpec;
-import java.util.ArrayList;
 import java.util.EnumSet;
-import java.util.List;
 
 @Data
 @With
@@ -36,13 +34,7 @@ public class ClientboundPlayerInfoUpdatePacket implements MinecraftPacket {
                 switch (action) {
                     case ADD_PLAYER -> {
                         GameProfile profile = new GameProfile(entry.getProfileId(), helper.readString(in, 16));
-                        int propertyCount = helper.readVarInt(in);
+                        profile.setProperties(helper.readList(in, helper::readProperty));
-                        List<GameProfile.Property> propertyList = new ArrayList<>();
-                        for (int index = 0; index < propertyCount; index++) {
-                            propertyList.add(helper.readProperty(in));
-                        }
-
-                        profile.setProperties(propertyList);
 
                         entry.setProfile(profile);
                     }
@@ -104,10 +96,7 @@ public class ClientboundPlayerInfoUpdatePacket implements MinecraftPacket {
                         }
 
                         helper.writeString(out, profile.getName());
-                        helper.writeVarInt(out, profile.getProperties().size());
+                        helper.writeList(out, profile.getProperties(), helper::writeProperty);
-                        for (GameProfile.Property property : profile.getProperties()) {
-                            helper.writeProperty(out, property);
-                        }
                     }
                     case INITIALIZE_CHAT -> {
                         out.writeBoolean(entry.getPublicKey() != null);

protocol/src/main/java/org/geysermc/mcprotocollib/protocol/packet/ingame/clientbound/ClientboundSelectAdvancementsTabPacket.java

@@ -4,6 +4,7 @@ import io.netty.buffer.ByteBuf;
 import lombok.AllArgsConstructor;
 import lombok.Data;
 import lombok.With;
+import org.checkerframework.checker.nullness.qual.Nullable;
 import org.geysermc.mcprotocollib.protocol.codec.MinecraftCodecHelper;
 import org.geysermc.mcprotocollib.protocol.codec.MinecraftPacket;
 
@@ -11,23 +12,14 @@ import org.geysermc.mcprotocollib.protocol.codec.MinecraftPacket;
 @With
 @AllArgsConstructor
 public class ClientboundSelectAdvancementsTabPacket implements MinecraftPacket {
-    private final String tabId;
+    private final @Nullable String tabId;
 
     public ClientboundSelectAdvancementsTabPacket(ByteBuf in, MinecraftCodecHelper helper) {
-        if (in.readBoolean()) {
+        this.tabId = helper.readNullable(in, helper::readString);
-            this.tabId = helper.readString(in);
-        } else {
-            this.tabId = null;
-        }
     }
 
     @Override
     public void serialize(ByteBuf out, MinecraftCodecHelper helper) {
-        if (this.tabId != null) {
+        helper.writeNullable(out, this.tabId, helper::writeString);
-            out.writeBoolean(true);
-            helper.writeString(out, this.tabId);
-        } else {
-            out.writeBoolean(false);
-        }
     }
 }

protocol/src/main/java/org/geysermc/mcprotocollib/protocol/packet/ingame/clientbound/ClientboundUpdateAdvancementsPacket.java

@@ -13,7 +13,6 @@ import org.geysermc.mcprotocollib.protocol.data.game.advancement.Advancement.Dis
 import org.geysermc.mcprotocollib.protocol.data.game.advancement.Advancement.DisplayData.AdvancementType;
 import org.geysermc.mcprotocollib.protocol.data.game.item.ItemStack;
 
-import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
@@ -51,36 +50,25 @@ public class ClientboundUpdateAdvancementsPacket implements MinecraftPacket {
         for (int i = 0; i < this.advancements.length; i++) {
             String id = helper.readString(in);
             String parentId = helper.readNullable(in, helper::readString);
-            DisplayData displayData = null;
+            DisplayData displayData = helper.readNullable(in, buf -> {
-            if (in.readBoolean()) {
+                Component title = helper.readComponent(buf);
-                Component title = helper.readComponent(in);
+                Component description = helper.readComponent(buf);
-                Component description = helper.readComponent(in);
+                ItemStack icon = helper.readOptionalItemStack(buf);
-                ItemStack icon = helper.readOptionalItemStack(in);
+                AdvancementType advancementType = AdvancementType.from(helper.readVarInt(buf));
-                AdvancementType advancementType = AdvancementType.from(helper.readVarInt(in));
 
-                int flags = in.readInt();
+                int flags = buf.readInt();
                 boolean hasBackgroundTexture = (flags & FLAG_HAS_BACKGROUND_TEXTURE) != 0;
                 boolean showToast = (flags & FLAG_SHOW_TOAST) != 0;
                 boolean hidden = (flags & FLAG_HIDDEN) != 0;
 
-                String backgroundTexture = hasBackgroundTexture ? helper.readString(in) : null;
+                String backgroundTexture = hasBackgroundTexture ? helper.readString(buf) : null;
-                float posX = in.readFloat();
+                float posX = buf.readFloat();
-                float posY = in.readFloat();
+                float posY = buf.readFloat();
 
-                displayData = new DisplayData(title, description, icon, advancementType, showToast, hidden, posX, posY, backgroundTexture);
+                return new DisplayData(title, description, icon, advancementType, showToast, hidden, posX, posY, backgroundTexture);
-            }
+            });
 
-            List<List<String>> requirements = new ArrayList<>();
+            List<List<String>> requirements = helper.readList(in, buf -> helper.readList(buf, helper::readString));
-            int requirementCount = helper.readVarInt(in);
-            for (int j = 0; j < requirementCount; j++) {
-                List<String> requirement = new ArrayList<>();
-                int componentCount = helper.readVarInt(in);
-                for (int k = 0; k < componentCount; k++) {
-                    requirement.add(helper.readString(in));
-                }
-
-                requirements.add(requirement);
-            }
 
             boolean sendTelemetryEvent = in.readBoolean();
 
@@ -123,47 +111,36 @@ public class ClientboundUpdateAdvancementsPacket implements MinecraftPacket {
                 out.writeBoolean(false);
             }
 
-            DisplayData displayData = advancement.getDisplayData();
+            helper.writeNullable(out, advancement.getDisplayData(), (buf, data) -> {
-            if (displayData != null) {
+                helper.writeComponent(buf, data.getTitle());
-                out.writeBoolean(true);
+                helper.writeComponent(buf, data.getDescription());
-                helper.writeComponent(out, displayData.getTitle());
+                helper.writeOptionalItemStack(buf, data.getIcon());
-                helper.writeComponent(out, displayData.getDescription());
+                helper.writeVarInt(buf, data.getAdvancementType().ordinal());
-                helper.writeOptionalItemStack(out, displayData.getIcon());
-                helper.writeVarInt(out, displayData.getAdvancementType().ordinal());
-                String backgroundTexture = displayData.getBackgroundTexture();
 
                 int flags = 0;
-                if (backgroundTexture != null) {
+                if (data.getBackgroundTexture() != null) {
                     flags |= FLAG_HAS_BACKGROUND_TEXTURE;
                 }
 
-                if (displayData.isShowToast()) {
+                if (data.isShowToast()) {
                     flags |= FLAG_SHOW_TOAST;
                 }
 
-                if (displayData.isHidden()) {
+                if (data.isHidden()) {
                     flags |= FLAG_HIDDEN;
                 }
 
-                out.writeInt(flags);
+                buf.writeInt(flags);
 
-                if (backgroundTexture != null) {
+                if (data.getBackgroundTexture() != null) {
-                    helper.writeString(out, backgroundTexture);
+                    helper.writeString(buf, data.getBackgroundTexture());
                 }
 
-                out.writeFloat(displayData.getPosX());
+                buf.writeFloat(data.getPosX());
-                out.writeFloat(displayData.getPosY());
+                buf.writeFloat(data.getPosY());
-            } else {
+            });
-                out.writeBoolean(false);
-            }
 
-            helper.writeVarInt(out, advancement.getRequirements().size());
+            helper.writeList(out, advancement.getRequirements(), (buf, requirement) -> helper.writeList(buf, requirement, helper::writeString));
-            for (List<String> requirement : advancement.getRequirements()) {
-                helper.writeVarInt(out, requirement.size());
-                for (String criterion : requirement) {
-                    helper.writeString(out, criterion);
-                }
-            }
 
             out.writeBoolean(advancement.isSendsTelemetryEvent());
         }

protocol/src/main/java/org/geysermc/mcprotocollib/protocol/packet/ingame/clientbound/level/ClientboundChunksBiomesPacket.java

@@ -7,7 +7,6 @@ import org.geysermc.mcprotocollib.protocol.codec.MinecraftCodecHelper;
 import org.geysermc.mcprotocollib.protocol.codec.MinecraftPacket;
 import org.geysermc.mcprotocollib.protocol.data.game.chunk.ChunkBiomeData;
 
-import java.util.ArrayList;
 import java.util.List;
 
 @Data
@@ -16,22 +15,18 @@ public class ClientboundChunksBiomesPacket implements MinecraftPacket {
     private final List<ChunkBiomeData> chunkBiomeData;
 
     public ClientboundChunksBiomesPacket(ByteBuf in, MinecraftCodecHelper helper) {
-        this.chunkBiomeData = new ArrayList<>();
+        this.chunkBiomeData = helper.readList(in, buf -> {
-
+            long raw = buf.readLong();
-        int length = helper.readVarInt(in);
+            return new ChunkBiomeData((int) raw, (int) (raw >> 32), helper.readByteArray(buf));
-        for (int i = 0; i < length; i++) {
+        });
-            long raw = in.readLong();
-            this.chunkBiomeData.add(new ChunkBiomeData((int) raw, (int) (raw >> 32), helper.readByteArray(in)));
-        }
     }
 
     @Override
     public void serialize(ByteBuf out, MinecraftCodecHelper helper) {
-        helper.writeVarInt(out, this.chunkBiomeData.size());
+        helper.writeList(out, this.chunkBiomeData, (buf, entry) -> {
-        for (ChunkBiomeData entry : this.chunkBiomeData) {
             long raw = (long) entry.getX() & 0xFFFFFFFFL | ((long) entry.getZ() & 0xFFFFFFFFL) << 32;
-            out.writeLong(raw);
+            buf.writeLong(raw);
-            helper.writeByteArray(out, entry.getBuffer());
+            helper.writeByteArray(buf, entry.getBuffer());
-        }
+        });
     }
 }

protocol/src/main/java/org/geysermc/mcprotocollib/protocol/packet/ingame/clientbound/level/ClientboundExplodePacket.java

@@ -10,9 +10,10 @@ import org.geysermc.mcprotocollib.protocol.codec.MinecraftCodecHelper;
 import org.geysermc.mcprotocollib.protocol.codec.MinecraftPacket;
 import org.geysermc.mcprotocollib.protocol.data.game.level.block.ExplosionInteraction;
 import org.geysermc.mcprotocollib.protocol.data.game.level.particle.Particle;
+import org.geysermc.mcprotocollib.protocol.data.game.level.sound.BuiltinSound;
+import org.geysermc.mcprotocollib.protocol.data.game.level.sound.CustomSound;
 import org.geysermc.mcprotocollib.protocol.data.game.level.sound.Sound;
 
-import java.util.ArrayList;
 import java.util.List;
 
 @Data
@@ -37,11 +38,7 @@ public class ClientboundExplodePacket implements MinecraftPacket {
         this.y = in.readDouble();
         this.z = in.readDouble();
         this.radius = in.readFloat();
-        this.exploded = new ArrayList<>();
+        this.exploded = helper.readList(in, buf -> Vector3i.from(buf.readByte(), buf.readByte(), buf.readByte()));
-        int length = helper.readVarInt(in);
-        for (int count = 0; count < length; count++) {
-            this.exploded.add(Vector3i.from(in.readByte(), in.readByte(), in.readByte()));
-        }
 
         this.pushX = in.readFloat();
         this.pushY = in.readFloat();
@@ -49,7 +46,7 @@ public class ClientboundExplodePacket implements MinecraftPacket {
         this.blockInteraction = ExplosionInteraction.from(helper.readVarInt(in)); // different order than mojang fields
         this.smallExplosionParticles = helper.readParticle(in);
         this.largeExplosionParticles = helper.readParticle(in);
-        this.explosionSound = helper.readSoundEvent(in);
+        this.explosionSound = helper.readById(in, BuiltinSound::from, helper::readSoundEvent);
     }
 
     @Override
@@ -58,12 +55,11 @@ public class ClientboundExplodePacket implements MinecraftPacket {
         out.writeDouble(this.y);
         out.writeDouble(this.z);
         out.writeFloat(this.radius);
-        helper.writeVarInt(out, this.exploded.size());
+        helper.writeList(out, this.exploded, (buf, record) -> {
-        for (Vector3i record : this.exploded) {
+            buf.writeByte(record.getX());
-            out.writeByte(record.getX());
+            buf.writeByte(record.getY());
-            out.writeByte(record.getY());
+            buf.writeByte(record.getZ());
-            out.writeByte(record.getZ());
+        });
-        }
 
         out.writeFloat(this.pushX);
         out.writeFloat(this.pushY);
@@ -71,6 +67,11 @@ public class ClientboundExplodePacket implements MinecraftPacket {
         helper.writeVarInt(out, this.blockInteraction.ordinal()); // different order than mojang fields
         helper.writeParticle(out, this.smallExplosionParticles);
         helper.writeParticle(out, this.largeExplosionParticles);
+        if (this.explosionSound instanceof CustomSound) {
+            helper.writeVarInt(out, 0);
             helper.writeSoundEvent(out, this.explosionSound);
+        } else {
+            helper.writeVarInt(out, ((BuiltinSound) this.explosionSound).ordinal() + 1);
+        }
     }
 }

protocol/src/main/java/org/geysermc/mcprotocollib/protocol/packet/ingame/clientbound/level/ClientboundMapItemDataPacket.java

@@ -39,10 +39,7 @@ public class ClientboundMapItemDataPacket implements MinecraftPacket {
                 int x = in.readByte();
                 int z = in.readByte();
                 int rotation = in.readByte();
-                Component displayName = null;
+                Component displayName = helper.readNullable(in, helper::readComponent);
-                if (in.readBoolean()) {
-                    displayName = helper.readComponent(in);
-                }
 
                 this.icons[index] = new MapIcon(x, z, MapIconType.from(type), rotation, displayName);
             }
@@ -75,12 +72,7 @@ public class ClientboundMapItemDataPacket implements MinecraftPacket {
                 out.writeByte(icon.getCenterX());
                 out.writeByte(icon.getCenterZ());
                 out.writeByte(icon.getIconRotation());
-                if (icon.getDisplayName() != null) {
+                helper.writeNullable(out, icon.getDisplayName(), helper::writeComponent);
-                    out.writeBoolean(true);
-                    helper.writeComponent(out, icon.getDisplayName());
-                } else {
-                    out.writeBoolean(false);
-                }
             }
         } else {
             out.writeBoolean(false);

protocol/src/main/java/org/geysermc/mcprotocollib/protocol/packet/ingame/serverbound/ServerboundChatPacket.java

@@ -26,12 +26,11 @@ public class ServerboundChatPacket implements MinecraftPacket {
         this.message = helper.readString(in);
         this.timeStamp = in.readLong();
         this.salt = in.readLong();
-        if (in.readBoolean()) {
+        this.signature = helper.readNullable(in, buf -> {
-            this.signature = new byte[256];
+            byte[] signature = new byte[256];
-            in.readBytes(this.signature);
+            buf.readBytes(signature);
-        } else {
+            return signature;
-            this.signature = null;
+        });
-        }
 
         this.offset = helper.readVarInt(in);
         this.acknowledgedMessages = helper.readFixedBitSet(in, 20);
@@ -42,10 +41,7 @@ public class ServerboundChatPacket implements MinecraftPacket {
         helper.writeString(out, this.message);
         out.writeLong(this.timeStamp);
         out.writeLong(this.salt);
-        out.writeBoolean(this.signature != null);
+        helper.writeNullable(out, this.signature, ByteBuf::writeBytes);
-        if (this.signature != null) {
-            out.writeBytes(this.signature);
-        }
 
         helper.writeVarInt(out, this.offset);
         helper.writeFixedBitSet(out, this.acknowledgedMessages, 20);

protocol/src/main/java/org/geysermc/mcprotocollib/protocol/packet/ingame/serverbound/inventory/ServerboundEditBookPacket.java

@@ -8,7 +8,6 @@ import org.checkerframework.checker.nullness.qual.Nullable;
 import org.geysermc.mcprotocollib.protocol.codec.MinecraftCodecHelper;
 import org.geysermc.mcprotocollib.protocol.codec.MinecraftPacket;
 
-import java.util.ArrayList;
 import java.util.List;
 
 @Data
@@ -21,28 +20,14 @@ public class ServerboundEditBookPacket implements MinecraftPacket {
 
     public ServerboundEditBookPacket(ByteBuf in, MinecraftCodecHelper helper) {
         this.slot = helper.readVarInt(in);
-        this.pages = new ArrayList<>();
+        this.pages = helper.readList(in, helper::readString);
-        int pagesSize = helper.readVarInt(in);
+        this.title = helper.readNullable(in, helper::readString);
-        for (int i = 0; i < pagesSize; i++) {
-            this.pages.add(helper.readString(in));
-        }
-        if (in.readBoolean()) {
-            this.title = helper.readString(in);
-        } else {
-            this.title = null;
-        }
     }
 
     @Override
     public void serialize(ByteBuf out, MinecraftCodecHelper helper) {
         helper.writeVarInt(out, slot);
-        helper.writeVarInt(out, this.pages.size());
+        helper.writeList(out, pages, helper::writeString);
-        for (String page : this.pages) {
+        helper.writeNullable(out, title, helper::writeString);
-            helper.writeString(out, page);
-        }
-        out.writeBoolean(this.title != null);
-        if (this.title != null) {
-            helper.writeString(out, title);
-        }
     }
 }

protocol/src/main/java/org/geysermc/mcprotocollib/protocol/packet/login/clientbound/ClientboundGameProfilePacket.java

@@ -9,9 +9,6 @@ import lombok.With;
 import org.geysermc.mcprotocollib.protocol.codec.MinecraftCodecHelper;
 import org.geysermc.mcprotocollib.protocol.codec.MinecraftPacket;
 
-import java.util.ArrayList;
-import java.util.List;
-
 @Data
 @With
 @AllArgsConstructor
@@ -21,20 +18,7 @@ public class ClientboundGameProfilePacket implements MinecraftPacket {
 
     public ClientboundGameProfilePacket(ByteBuf in, MinecraftCodecHelper helper) {
         GameProfile profile = new GameProfile(helper.readUUID(in), helper.readString(in));
-        int properties = helper.readVarInt(in);
+        profile.setProperties(helper.readList(in, helper::readProperty));
-        List<GameProfile.Property> propertyList = new ArrayList<>();
-        for (int index = 0; index < properties; index++) {
-            String propertyName = helper.readString(in);
-            String value = helper.readString(in);
-            String signature = null;
-            if (in.readBoolean()) {
-                signature = helper.readString(in);
-            }
-
-            propertyList.add(new GameProfile.Property(propertyName, value, signature));
-        }
-
-        profile.setProperties(propertyList);
         this.profile = profile;
         this.strictErrorHandling = in.readBoolean();
     }
@@ -43,15 +27,7 @@ public class ClientboundGameProfilePacket implements MinecraftPacket {
     public void serialize(ByteBuf out, MinecraftCodecHelper helper) {
         helper.writeUUID(out, this.profile.getId());
         helper.writeString(out, this.profile.getName());
-        helper.writeVarInt(out, this.profile.getProperties().size());
+        helper.writeList(out, this.profile.getProperties(), helper::writeProperty);
-        for (GameProfile.Property property : this.profile.getProperties()) {
-            helper.writeString(out, property.getName());
-            helper.writeString(out, property.getValue());
-            out.writeBoolean(property.hasSignature());
-            if (property.hasSignature()) {
-                helper.writeString(out, property.getSignature());
-            }
-        }
         out.writeBoolean(this.strictErrorHandling);
     }