Add loading of new util.json mappings

core/src/main/java/org/geysermc/geyser/registry/Registries.java

@@ -29,6 +29,7 @@
 import it.unimi.dsi.fastutil.objects.Object2IntMap;
 import it.unimi.dsi.fastutil.objects.Object2ObjectMap;
 import it.unimi.dsi.fastutil.objects.Object2ObjectOpenHashMap;
+import net.kyori.adventure.key.Key;
 import org.cloudburstmc.nbt.NbtMap;
 import org.cloudburstmc.nbt.NbtMapBuilder;
 import org.cloudburstmc.protocol.bedrock.data.biome.BiomeDefinitions;
@@ -56,6 +57,7 @@
 import org.geysermc.geyser.registry.type.ItemMappings;
 import org.geysermc.geyser.registry.type.ParticleMapping;
 import org.geysermc.geyser.registry.type.SoundMapping;
+import org.geysermc.geyser.registry.type.UtilMappings;
 import org.geysermc.geyser.translator.level.block.entity.BlockEntityTranslator;
 import org.geysermc.geyser.translator.level.event.LevelEventTranslator;
 import org.geysermc.geyser.translator.sound.SoundInteractionTranslator;
@@ -197,6 +199,21 @@ public final class Registries {
      */
     public static final SimpleMappedDeferredRegistry<SoundTranslator, SoundInteractionTranslator<?>> SOUND_TRANSLATORS = SimpleMappedDeferredRegistry.create("org.geysermc.geyser.translator.sound.SoundTranslator", SoundTranslatorRegistryLoader::new);
 
+    /**
+     * A registry containing all of Java's "game master blocks" - blocks that can't be broken without operator permission level 2 or higher.
+     */
+    public static final ListDeferredRegistry<Key> GAME_MASTER_BLOCKS = ListDeferredRegistry.create(UtilMappings::gameMasterBlocks, RegistryLoaders.UTIL_MAPPINGS_KEYS);
+
+    /**
+     * A registry containing all block entities Java considers "dangerous" - these have a red warning in the item tooltip on Java.
+     */
+    public static final ListDeferredRegistry<Key> DANGEROUS_BLOCK_ENTITIES = ListDeferredRegistry.create(UtilMappings::dangerousBlockEntities, RegistryLoaders.UTIL_MAPPINGS_KEYS);
+
+    /**
+     * A registry containing all entities Java considers "dangerous" - spawn eggs of these entities have a red warning in the item tooltip on Java.
+     */
+    public static final ListDeferredRegistry<Key> DANGEROUS_ENTITIES = ListDeferredRegistry.create(UtilMappings::dangerousEntities, RegistryLoaders.UTIL_MAPPINGS_KEYS);
+
     public static void load() {
         if (loaded) return;
         loaded = true;
@@ -216,6 +233,10 @@ public static void load() {
         SOUNDS.load();
         SOUND_LEVEL_EVENTS.load();
         SOUND_TRANSLATORS.load();
+
+        GAME_MASTER_BLOCKS.load();
+        DANGEROUS_BLOCK_ENTITIES.load();
+        DANGEROUS_ENTITIES.load();
     }
 
     public static void populate() {

core/src/main/java/org/geysermc/geyser/registry/loader/RegistryLoaders.java

@@ -25,8 +25,11 @@
 
 package org.geysermc.geyser.registry.loader;
 
+import net.kyori.adventure.key.Key;
 import org.checkerframework.checker.nullness.qual.NonNull;
+import org.geysermc.geyser.registry.type.UtilMappings;
 
+import java.util.List;
 import java.util.function.Supplier;
 
 /**
@@ -48,6 +51,8 @@ public final class RegistryLoaders {
      */
     public static final ResourcePackLoader RESOURCE_PACKS = new ResourcePackLoader();
 
+    public static final UtilMappings.Loader<List<Key>> UTIL_MAPPINGS_KEYS = new UtilMappings.Loader<>();
+
     /**
      * Wraps the surrounding {@link Supplier} in a {@link RegistryLoader} which does
      * not take in any input value.

core/src/main/java/org/geysermc/geyser/registry/type/UtilMappings.java

@@ -0,0 +1,90 @@
+/*
+ * Copyright (c) 2025 GeyserMC. http://geysermc.org
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * @author GeyserMC
+ * @link https://github.com/GeyserMC/Geyser
+ */
+
+package org.geysermc.geyser.registry.type;
+
+import com.google.gson.JsonObject;
+import com.google.gson.JsonParser;
+import net.kyori.adventure.key.Key;
+import org.geysermc.geyser.GeyserImpl;
+import org.geysermc.geyser.registry.loader.RegistryLoader;
+import org.geysermc.geyser.util.MinecraftKey;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.function.Function;
+
+/**
+ * Used to load and store the {@code mappings/util.json} file. When adding new fields to util mappings, be sure to create a proper registry for them
+ * in {@link org.geysermc.geyser.registry.Registries}. Use {@link org.geysermc.geyser.registry.loader.RegistryLoaders#UTIL_MAPPINGS_KEYS} (or create a new loader if loading something
+ * other than keys).
+ */
+public record UtilMappings(List<Key> gameMasterBlocks, List<Key> dangerousBlockEntities, List<Key> dangerousEntities) {
+    private static final String INPUT = "mappings/util.json";
+    private static UtilMappings loaded = null;
+
+    /**
+     * Gets the loaded util mappings, or loads them if they weren't yet.
+     */
+    private static UtilMappings get() {
+        if (loaded == null) {
+            try (InputStream utilInput = GeyserImpl.getInstance().getBootstrap().getResourceOrThrow(INPUT)) {
+                JsonObject utilJson = JsonParser.parseReader(new InputStreamReader(utilInput)).getAsJsonObject();
+
+                List<Key> gameMasterBlocks = new ArrayList<>();
+                List<Key> dangerousBlockEntities = new ArrayList<>();
+                List<Key> dangerousEntities = new ArrayList<>();
+
+                utilJson.get("game_master_blocks").getAsJsonArray()
+                    .forEach(element -> gameMasterBlocks.add(MinecraftKey.key(element.getAsString())));
+                utilJson.get("dangerous_block_entities").getAsJsonArray()
+                    .forEach(element -> dangerousBlockEntities.add(MinecraftKey.key(element.getAsString())));
+                utilJson.get("dangerous_entities").getAsJsonArray()
+                    .forEach(element -> dangerousEntities.add(MinecraftKey.key(element.getAsString())));
+
+                loaded = new UtilMappings(List.copyOf(gameMasterBlocks), List.copyOf(dangerousBlockEntities), List.copyOf(dangerousEntities));
+            } catch (IOException e) {
+                throw new AssertionError("Failed to load " + INPUT);
+            }
+        }
+        return loaded;
+    }
+
+    /**
+     * Simply gets a field of the loaded {@link UtilMappings} object. Instead of re-opening the util mappings file every time a field is loaded,
+     * the mappings are parsed once by {@link UtilMappings#get()} and kept in a static variable.
+     * Loader input is a function that extracts the field to get from the {@link UtilMappings} object.
+     */
+    public static class Loader<T> implements RegistryLoader<Function<UtilMappings, T>, T> {
+
+        @Override
+        public T load(Function<UtilMappings, T> input) {
+            return input.apply(UtilMappings.get());
+        }
+    }
+}

core/src/main/java/org/geysermc/geyser/session/cache/BlockBreakHandler.java

@@ -50,6 +50,7 @@
 import org.geysermc.geyser.level.block.type.BlockState;
 import org.geysermc.geyser.level.physics.Direction;
 import org.geysermc.geyser.registry.BlockRegistries;
+import org.geysermc.geyser.registry.Registries;
 import org.geysermc.geyser.registry.type.ItemMapping;
 import org.geysermc.geyser.session.GeyserSession;
 import org.geysermc.geyser.translator.item.CustomItemTranslator;
@@ -76,16 +77,6 @@
  */
 public class BlockBreakHandler {
 
-    private final static Set<Block> GAME_MASTER_BLOCKS = Set.of(
-        Blocks.COMMAND_BLOCK,
-        Blocks.CHAIN_COMMAND_BLOCK,
-        Blocks.REPEATING_COMMAND_BLOCK,
-        Blocks.JIGSAW,
-        Blocks.STRUCTURE_BLOCK,
-        Blocks.TEST_BLOCK,
-        Blocks.TEST_INSTANCE_BLOCK
-    );
-
     protected final GeyserSession session;
 
     /**
@@ -457,7 +448,7 @@ protected boolean canDestroyBlock(BlockState state) {
             }
         }
 
-        if (GAME_MASTER_BLOCKS.contains(state.block())) {
+        if (Registries.GAME_MASTER_BLOCKS.get().contains(state.block().javaIdentifier())) {
             if (!instabuild || session.getOpPermissionLevel() < 2) {
                 return false;
             }