Updated version of HideChestOpeningMod

HideChestOpeningMod.java

package com.comphenix.hidechest;

import org.bukkit.Material;
import org.bukkit.World;
import org.bukkit.plugin.java.JavaPlugin;

import com.comphenix.protocol.PacketType;
import com.comphenix.protocol.ProtocolLibrary;
import com.comphenix.protocol.ProtocolManager;
import com.comphenix.protocol.events.PacketAdapter;
import com.comphenix.protocol.events.PacketEvent;
import com.comphenix.protocol.reflect.StructureModifier;

public class HideChestOpeningMod extends JavaPlugin {
    @Override
    public void onEnable() {
        ProtocolManager manager = ProtocolLibrary.getProtocolManager();
        
        manager.addPacketListener(new PacketAdapter(this, 
          PacketType.Play.Server.BLOCK_ACTION, PacketType.Play.Server.NAMED_SOUND_EFFECT) {
            @Override
            public void onPacketSending(PacketEvent event) {
                PacketType type = event.getPacketType();
                
                if (type == PacketType.Play.Server.BLOCK_ACTION) {
                    World world = event.getPlayer().getWorld();
                    StructureModifier<Integer> ints = event.getPacket().getSpecificModifier(int.class);
                    int blockX = ints.read(0);
                    int blockY = ints.read(1);
                    int blockZ = ints.read(2);
                    
                    // See if this is is a chest animation
                    if (world.getBlockAt(blockX, blockY, blockZ).getType() == Material.CHEST) {
                        // Don't send the animation
                        event.setCancelled(true);
                    }
                } else if (type == PacketType.Play.Server.NAMED_SOUND_EFFECT) {
                    String soundEffectName = event.getPacket().getSpecificModifier(String.class).read(0);
                    // Disable all "chest" sound effects
                    if (soundEffectName.contains("chest")) {
                        event.setCancelled(true);
                    }
                }
            }
        });
    }
}