Implemented new Plugin Message API - see http://dinnerbone.com/blog/2012/01/13/minecraft-plugin-channels-messaging/

src/main/java/net/minecraft/server/NetServerHandler.java

@@ -1,7 +1,9 @@
 package net.minecraft.server;
 
+import java.io.UnsupportedEncodingException;
 import java.util.ArrayList;
 import java.util.Random;
+import java.util.logging.Level;
 import java.util.logging.Logger;
 
 // CraftBukkit start
@@ -1101,4 +1103,31 @@ public class NetServerHandler extends NetHandler implements ICommandListener {
     public boolean c() {
         return true;
     }
+
+    // CraftBukkit start
+    @Override
+    public void a(Packet250CustomPayload packet) {
+        if (packet.tag.equals("REGISTER")) {
+            try {
+                String channels = new String(packet.data, "UTF8");
+                for (String channel : channels.split("\0")) {
+                    getPlayer().addChannel(channel);
+                }
+            } catch (UnsupportedEncodingException ex) {
+                Logger.getLogger(NetServerHandler.class.getName()).log(Level.SEVERE, "Could not parse REGISTER payload in plugin message packet", ex);
+            }
+        } else if (packet.tag.equals("UNREGISTER")) {
+            try {
+                String channels = new String(packet.data, "UTF8");
+                for (String channel : channels.split("\0")) {
+                    getPlayer().removeChannel(channel);
+                }
+            } catch (UnsupportedEncodingException ex) {
+                Logger.getLogger(NetServerHandler.class.getName()).log(Level.SEVERE, "Could not parse UNREGISTER payload in plugin message packet", ex);
+            }
+        } else {
+            server.getMessenger().dispatchIncomingMessage(player.getPlayer(), packet.tag, packet.data);
+        }
+    }
+    // CraftBukkit end
 }

src/main/java/org/bukkit/craftbukkit/CraftServer.java

@@ -67,6 +67,7 @@ import org.bukkit.plugin.ServicesManager;
 import org.bukkit.plugin.SimplePluginManager;
 import org.bukkit.plugin.SimpleServicesManager;
 import org.bukkit.plugin.java.JavaPluginLoader;
+import org.bukkit.plugin.messaging.Messenger;
 import org.bukkit.scheduler.BukkitScheduler;
 import org.bukkit.craftbukkit.inventory.CraftFurnaceRecipe;
 import org.bukkit.craftbukkit.inventory.CraftRecipe;
@@ -81,6 +82,7 @@ import org.bukkit.util.permissions.DefaultPermissions;
 import org.bukkit.event.world.WorldInitEvent;
 import org.bukkit.permissions.Permission;
 import org.bukkit.plugin.PluginLoadOrder;
+import org.bukkit.plugin.messaging.StandardMessenger;
 import org.yaml.snakeyaml.Yaml;
 import org.yaml.snakeyaml.constructor.SafeConstructor;
 import org.yaml.snakeyaml.error.MarkedYAMLException;
@@ -92,6 +94,7 @@ public final class CraftServer implements Server {
     private final ServicesManager servicesManager = new SimpleServicesManager();
     private final BukkitScheduler scheduler = new CraftScheduler(this);
     private final SimpleCommandMap commandMap = new SimpleCommandMap(this);
+    private final StandardMessenger messenger = new StandardMessenger();
     private final PluginManager pluginManager = new SimplePluginManager(this, commandMap);
     protected final MinecraftServer console;
     protected final ServerConfigurationManager server;
@@ -942,4 +945,26 @@ public final class CraftServer implements Server {
 
         return players.toArray(new OfflinePlayer[players.size()]);
     }
+
+    public Messenger getMessenger() {
+        return messenger;
+    }
+
+    public void sendPluginMessage(Plugin source, String channel, byte[] message) {
+        StandardMessenger.validatePluginMessage(getMessenger(), source, channel, message);
+
+        for (Player player : getOnlinePlayers()) {
+            player.sendPluginMessage(source, channel, message);
+        }
+    }
+
+    public Set<String> getListeningPluginChannels() {
+        Set<String> result = new HashSet<String>();
+
+        for (Player player : getOnlinePlayers()) {
+            result.addAll(player.getListeningPluginChannels());
+        }
+
+        return result;
+    }
 }

src/main/java/org/bukkit/craftbukkit/CraftWorld.java

@@ -2,11 +2,13 @@ package org.bukkit.craftbukkit;
 
 import com.google.common.collect.MapMaker;
 import java.io.File;
+import java.util.Set;
 import org.bukkit.craftbukkit.entity.*;
 import org.bukkit.entity.*;
 import org.bukkit.entity.Entity;
 
 import java.util.ArrayList;
+import java.util.HashSet;
 import java.util.concurrent.ConcurrentMap;
 import java.util.List;
 import java.util.Random;
@@ -25,6 +27,7 @@ import org.bukkit.block.BlockFace;
 import org.bukkit.entity.Boat;
 import org.bukkit.Chunk;
 import org.bukkit.inventory.ItemStack;
+import org.bukkit.plugin.Plugin;
 import org.bukkit.util.Vector;
 import org.bukkit.BlockChangeDelegate;
 import org.bukkit.Bukkit;
@@ -38,6 +41,7 @@ import org.bukkit.generator.BlockPopulator;
 import org.bukkit.Difficulty;
 import org.bukkit.craftbukkit.block.CraftBlock;
 import org.bukkit.craftbukkit.inventory.CraftItemStack;
+import org.bukkit.plugin.messaging.StandardMessenger;
 
 public class CraftWorld implements World {
     private final WorldServer world;
@@ -919,4 +923,22 @@ public class CraftWorld implements World {
         // For example, WOODEN_STAIRS does something with WOOD in this method
         net.minecraft.server.Block.byId[blockId].wasExploded(this.world, blockX, blockY, blockZ);
     }
+
+    public void sendPluginMessage(Plugin source, String channel, byte[] message) {
+        StandardMessenger.validatePluginMessage(server.getMessenger(), source, channel, message);
+
+        for (Player player : getPlayers()) {
+            player.sendPluginMessage(source, channel, message);
+        }
+    }
+
+    public Set<String> getListeningPluginChannels() {
+        Set<String> result = new HashSet<String>();
+
+        for (Player player : getPlayers()) {
+            result.addAll(player.getListeningPluginChannels());
+        }
+
+        return result;
+    }
 }

src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java

@@ -1,16 +1,18 @@
 package org.bukkit.craftbukkit.entity;
 
+import com.google.common.collect.ImmutableSet;
 import java.net.InetSocketAddress;
 import java.net.SocketAddress;
-import java.util.Calendar;
-import java.util.Date;
+import java.util.HashSet;
 import java.util.LinkedHashMap;
 import java.util.Map;
+import java.util.Set;
 import net.minecraft.server.EntityPlayer;
 import net.minecraft.server.NBTTagCompound;
 import net.minecraft.server.Packet131ItemData;
 import net.minecraft.server.Packet200Statistic;
 import net.minecraft.server.Packet201PlayerInfo;
+import net.minecraft.server.Packet250CustomPayload;
 import net.minecraft.server.Packet3Chat;
 import net.minecraft.server.Packet51MapChunk;
 import net.minecraft.server.Packet53BlockChange;
@@ -39,12 +41,15 @@ import org.bukkit.entity.Player;
 import org.bukkit.event.player.PlayerGameModeChangeEvent;
 import org.bukkit.event.player.PlayerTeleportEvent;
 import org.bukkit.map.MapView;
+import org.bukkit.plugin.Plugin;
+import org.bukkit.plugin.messaging.StandardMessenger;
 
 @DelegateDeserialization(CraftOfflinePlayer.class)
 public class CraftPlayer extends CraftHumanEntity implements Player {
     private long firstPlayed = 0;
     private long lastPlayed = 0;
     private boolean hasPlayedBefore = false;
+    private Set<String> channels = new HashSet<String>();
 
     public CraftPlayer(CraftServer server, EntityPlayer entity) {
         super(server, entity);
@@ -616,4 +621,28 @@ public class CraftPlayer extends CraftHumanEntity implements Player {
         data.setLong("firstPlayed", getFirstPlayed());
         data.setLong("lastPlayed", System.currentTimeMillis());
     }
+
+    public void sendPluginMessage(Plugin source, String channel, byte[] message) {
+        StandardMessenger.validatePluginMessage(server.getMessenger(), source, channel, message);
+
+        if (channels.contains(channel)) {
+            Packet250CustomPayload packet = new Packet250CustomPayload();
+            packet.tag = channel;
+            packet.length = message.length;
+            packet.data = message;
+            getHandle().netServerHandler.sendPacket(packet);
+        }
+    }
+
+    public void addChannel(String channel) {
+        channels.add(channel);
+    }
+
+    public void removeChannel(String channel) {
+        channels.remove(channel);
+    }
+
+    public Set<String> getListeningPluginChannels() {
+        return ImmutableSet.copyOf(channels);
+    }
 }