Rebase the MessageHandler, MessageHandlerChain and MessageHandlerChainSet

Rebased several other pieces of code

data/plugins/bank/bank.rb

@@ -30,17 +30,17 @@ class BankAction < DistancedAction
 end
 
 # Intercepts the object action message
-on :message, :second_object_action do |ctx, player, message|
+on :message, :second_object_action do |player, message|
   if message.id == BANK_BOOTH_ID
     player.start_action(BankAction.new(player, message.position))
-    ctx.break_handler_chain
+    message.terminate
   end
 end
 
-on :message, :second_npc_action do |ctx, player, message|
+on :message, :second_npc_action do |player, message|
   npc = $world.npc_repository.get(message.index)
   if BANKER_NPCS.include?(npc.id)
     player.start_action(BankAction.new(player, npc.position))
-    ctx.break_handler_chain
+    message.terminate
   end
 end

data/plugins/bootstrap.rb

@@ -15,7 +15,7 @@
 require 'java'
 
 java_import 'org.apollo.game.command.CommandListener'
-java_import 'org.apollo.game.message.handler.MessageHandler'
+java_import 'org.apollo.game.message.MessageHandler'
 java_import 'org.apollo.game.model.World'
 java_import 'org.apollo.game.model.entity.Player'
 java_import 'org.apollo.game.model.event.EventListener'
@@ -75,11 +75,10 @@ class ProcEventListener
 
 end
 
-# A MessageHandler which executes a Proc object with three arguments: the chain
+# A MessageHandler which executes a Proc object with two arguments: the player and the message.
-# context, the player and the message.
 class ProcMessageHandler < MessageHandler
 
-  # Creates the ProcMessageListener.
+  # Creates the ProcMessageHandler.
   def initialize(block, option)
     super($world)
     @block = block
@@ -87,8 +86,8 @@ class ProcMessageHandler < MessageHandler
   end
 
   # Handles the message.
-  def handle(ctx, player, message)
+  def handle(player, message)
-    @block.call(ctx, player, message) if (@option == 0 || @option == message.option)
+    @block.call(player, message) if (@option == 0 || @option == message.option)
   end
 
 end
@@ -166,7 +165,7 @@ def on_button(args, proc)
 
   id = args[0].to_i
 
-  on :message, :button do |ctx, player, message|
+  on :message, :button do |player, message|
     proc.call(player) if message.widget_id == id
   end
 end
@@ -192,7 +191,7 @@ def on_message(args, proc)
   class_name = message.to_s.camelize.concat('Message')
   message = Java::JavaClass.for_name("org.apollo.game.message.impl.#{class_name}")
 
-  $ctx.add_last_message_handler(message, ProcMessageHandler.new(proc, option))
+  $ctx.add_message_handler(message, ProcMessageHandler.new(proc, option))
 end
 
 # Defines an action to be taken upon a command.

data/plugins/chat/privacy/privacy.rb

@@ -3,7 +3,7 @@ require 'java'
 java_import 'org.apollo.game.model.entity.setting.PrivacyState'
 java_import 'org.apollo.game.message.impl.SendFriendMessage'
 
-on :message, :privacy_option do |ctx, player, message|
+on :message, :privacy_option do |player, message|
   player.chat_privacy = message.chat_privacy
   player.friend_privacy = message.friend_privacy
   player.trade_privacy = message.trade_privacy

data/plugins/chat/private-messaging/friend.rb

@@ -11,7 +11,7 @@ java_import 'org.apollo.game.model.entity.Player'
 
 
 # Processes an add friend message, updating the logged-in status of the player (and the person they added) if necessary.
-on :message, :add_friend do |ctx, player, message|
+on :message, :add_friend do |player, message|
   friend_username = message.username
   player_username = player.username
 
@@ -30,7 +30,7 @@ on :message, :add_friend do |ctx, player, message|
 end
 
 # Processes a remove friend message, updating the logged-in status of the player if necessary.
-on :message, :remove_friend do |ctx, player, message|
+on :message, :remove_friend do |player, message|
   friend_username = message.username
   player_username = player.username
 

data/plugins/chat/private-messaging/ignore.rb

@@ -1,9 +1,9 @@
-on :message, :add_ignore do |ctx, player, message|
+on :message, :add_ignore do |player, message|
   username = message.username
   player.add_ignore(username)
 end
 
-on :message, :remove_ignore do |ctx, player, message|
+on :message, :remove_ignore do |player, message|
   username = message.username
   player.remove_ignore(username)
 end

data/plugins/chat/private-messaging/messaging.rb

@@ -4,7 +4,7 @@ java_import 'org.apollo.game.message.impl.ForwardPrivateChatMessage'
 java_import 'org.apollo.game.model.World'
 java_import 'org.apollo.game.model.entity.setting.PrivacyState'
 
-on :message, :private_chat do |ctx, player, message|
+on :message, :private_chat do |player, message|
   friend = $world.get_player(message.username)
   friend.send(ForwardPrivateChatMessage.new(player.username, player.privilege_level, message.compressed_chat)) if interaction_permitted(player, friend)
 end

data/plugins/consumables/consumable.rb

@@ -54,11 +54,11 @@ class ConsumeAction < Action
 end
 
 # Intercepts the first item option message and consumes the consumable, if necessary.
-on :message, :first_item_option do |ctx, player, message|
+on :message, :first_item_option do |player, message|
   consumable = CONSUMABLES[message.id]
 
   unless consumable.nil?
     player.start_action(ConsumeAction.new(player, message.slot, consumable))
-    ctx.break_handler_chain
+    message.terminate
   end
 end

data/plugins/dialogue/dialogue.rb

@@ -71,13 +71,13 @@ class Conversation
       raise 'Npc cannot be null when opening a dialogue.' if npc_index.nil?
       @starters << dialogue
 
-      on :message, :first_npc_action do |ctx, player, event|
+      on :message, :first_npc_action do |player, message|
-        npc = $world.npc_repository.get(event.index)
+        npc = $world.npc_repository.get(message.index)
         if npc_index == npc.id
           @starters.each do |start|
             if dialogue.precondition(player)
               player.start_action(OpenDialogueAction.new(player, npc, dialogue))
-      	      ctx.break_handler_chain()
+      	      message.terminate
       	      break
       	    end
       	  end

data/plugins/dummy/dummy.rb

@@ -45,6 +45,6 @@ class DummyAction < DistancedAction
   end
 end
 
-on :message, :second_object_action do |ctx, player, message|
+on :message, :second_object_action do |player, message|
   player.start_action(DummyAction.new(player, message.position)) if message.id == DUMMY_ID
 end

data/plugins/emote-tab/emote-tab.rb

@@ -12,10 +12,10 @@ ANIMATIONS = {
 }
 
 # Intercept the button message.
-on :message, :button do |ctx, player, message|
+on :message, :button do |player, message|
   anim = ANIMATIONS[message.widget_id]
   unless anim == nil
     player.play_animation(anim)
-    ctx.break_handler_chain
+    message.terminate
   end
 end

data/plugins/location/tutorial-island/survival.rb

@@ -126,7 +126,7 @@ def add_survival_items(player)
 end
 
 # Intercept the FirstObjectActionMessage to send tutorial-only events if the player is chopping down a tree.
-on :message, :first_object_action do |ctx, player, message|
+on :message, :first_object_action do |player, message|
   if (player.in_tutorial_island && message.id == SurvivalConstants::TREE_ID)
     progress = player.tutorial_island_progress
     if (progress < :cut_tree)
@@ -138,9 +138,9 @@ on :message, :first_object_action do |ctx, player, message|
 end
 
 # Intercept the FlashingTabClickedMessage to update the player's progress, if applicable.
-on :message, :flashing_tab_clicked do |ctx, player, message|
+on :message, :flashing_tab_clicked do |player, message|
   if (player.in_tutorial_island && message.tab == SurvivalConstants::INVENTORY_TAB_INDEX && player.tutorial_island_progress == :given_axe)
     player.tutorial_island_progress = :cut_tree
-    ctx.break_handler_chain()
+    message.terminate
   end
 end

data/plugins/navigation/door/door.rb

@@ -23,8 +23,8 @@ class OpenDoorAction < DistancedAction
 
 end
 
-# Message handler for opening and closing doors.
+# MessageListener for opening and closing doors.
-on :message, :first_object_action do |ctx, player, message|
+on :message, :first_object_action do |player, message|
   if DoorUtil::is_door?(message.id)
     puts "Player: #{player.position}, door: #{message.position}"
     door = DoorUtil::get_door_object(message.position, message.id)

data/plugins/skill/fishing/fishing.rb

@@ -100,12 +100,12 @@ class FishingAction < DistancedAction
 end
 
 # Intercepts the NpcAction message to determine whether or not a clicked npc was a fishing spot.
-on :message, :npc_action do |ctx, player, message|
+on :message, :npc_action do |player, message|
   npc = $world.npc_repository.get(message.index)
   spot = FISHING_SPOTS[npc.id]
 
 	unless spot.nil?
 	  player.start_action(FishingAction.new(player, npc.position, spot, message.option))
-	  ctx.break_handler_chain
+	  message.terminate
   end
 end

data/plugins/skill/herblore/herblore.rb

@@ -25,8 +25,8 @@ module HerbloreMethod
   end
 end
 
-# The ItemOnItemMessage handler for all Herblore-related functions.
+# The ItemOnItemMessage listener for all Herblore-related functions.
-on :message, :item_on_item do |ctx, player, message|
+on :message, :item_on_item do |player, message|
   primary = message.id
   secondary = message.target_id
   hash = HERBLORE_ITEM_ON_ITEM[primary]
@@ -41,25 +41,25 @@ on :message, :item_on_item do |ctx, player, message|
     method = hash[secondary]
     unless method.nil?
       method.invoke(player, primary, secondary)
-      ctx.break_handler_chain
+      message.terminate
     end
   end
 end
 
-# The ItemOptionMessage handler for all Herblore-related functions.
+# The ItemOptionMessage listener for all Herblore-related functions.
-on :message, :first_item_option do |ctx, player, message|
+on :message, :first_item_option do |player, message|
   id = message.id
   method = HERBLORE_ITEM[id]
 
   unless method.nil?
     method.invoke(player, id, message.slot)
-    ctx.break_handler_chain
+    message.terminate
   end
   method = DRINK_ITEM[id]
 
   unless method.nil?
     method.invoke(player, id, message.slot)
-    ctx.break_handler_chain
+    message.terminate
   end
 end
 

data/plugins/skill/herblore/ingredient.rb

@@ -223,7 +223,7 @@ class GrindingAction < Action
   end
 end
 
-# Appends a ground ingredient to the ItemOnItemMessage handler interception.
+# Appends a ground ingredient to the ItemOnItemMessage listener interception.
 def append_ground(id, raw)
   ground = GroundIngredient.new(id, raw)
   append_herblore_item(ground, PESTLE_MORTAR, raw)

data/plugins/skill/magic/magic.rb

@@ -118,7 +118,7 @@ class ItemSpellAction < SpellAction
 end
 
 # Intercepts the magic on item message.
-on :message, :magic_on_item do |ctx, player, message|
+on :message, :magic_on_item do |player, message|
   spell = message.spell_id
   
   alch = ALCHEMY_SPELLS[spell]
@@ -126,7 +126,7 @@ on :message, :magic_on_item do |ctx, player, message|
     slot = message.slot
     item = player.inventory.get(slot)
     player.start_action(AlchemyAction.new(player, alch, slot, item))
-    ctx.break_handler_chain
+    message.terminate
     return
   end
   
@@ -135,18 +135,18 @@ on :message, :magic_on_item do |ctx, player, message|
     slot = message.slot
     item = player.inventory.get(slot)
     player.start_action(EnchantAction.new(player, ench, slot, item, ENCHANT_ITEMS[item.id]))
-    ctx.break_handler_chain
+    message.terminate
   end
 end
 
 # Intercepts the button message
-on :message, :button do |ctx, player, message|
+on :message, :button do |player, message|
   button = message.widget_id
 
   tele = TELEPORT_SPELLS[button]
   unless tele.nil?
     player.start_action(TeleportingAction.new(player, tele))
-    ctx.break_handler_chain
+    message.terminate
     return
   end
   
@@ -155,6 +155,6 @@ on :message, :button do |ctx, player, message|
     slots = bone_slots player
 
     if slots.length == 0 then player.send_message("You can't convert these bones!") else player.start_action(ConvertingAction.new(player, conv, slots)) end
-    ctx.break_handler_chain
+    message.terminate
   end
 end

data/plugins/skill/mining/mining.rb

@@ -134,7 +134,7 @@ class ProspectingAction < DistancedAction
 
 end
 
-on :message, :first_object_action do |ctx, mob, message|
+on :message, :first_object_action do |mob, message|
   ore = ORES[message.id]
 
   unless ore.nil?
@@ -142,7 +142,7 @@ on :message, :first_object_action do |ctx, mob, message|
   end
 end
 
-on :message, :second_object_action do |ctx, mob, message|
+on :message, :second_object_action do |mob, message|
   ore = ORES[message.id]
 
   if !ore.nil?

data/plugins/skill/prayer/bury.rb

@@ -51,11 +51,11 @@ class BuryBoneAction < Action
 end
 
 # Intercepts the first item option message.
-on :message, :first_item_option do |ctx, player, message|
+on :message, :first_item_option do |player, message|
   bone = BONES[message.id]
   unless bone == nil
     player.start_action(BuryBoneAction.new(player, message.slot, bone))
-    ctx.break_handler_chain
+    message.terminate
   end
 end
 

data/plugins/skill/prayer/prayers.rb

@@ -9,7 +9,7 @@ declare_attribute(:active_prayer, -1, :persistent)
 PRAYERS = {}
 
 # Intercept the ButtonMessage to toggle a prayer.
-on :message, :button do |ctx, player, message|
+on :message, :button do |player, message|
     button = message.widget_id
 	prayer = PRAYERS[button]
 

data/plugins/skill/runecraft/altar.rb

@@ -24,26 +24,26 @@ end
 
 
 # Intercepts the item on object message.
-on :message, :item_on_object do |ctx, player, message|
+on :message, :item_on_object do |player, message|
   talisman = TALISMANS[message.id]; altar = ENTRANCE_ALTARS[message.object_id]
   unless (talisman.nil? || altar.nil?)
     player.start_action(TeleportAction.new(player, message.position, 2, altar.entrance_position))
-    ctx.break_handler_chain
+    message.terminate
   end
 end
 
 # Intercepts the first object action message.
-on :message, :object_action do |ctx, player, message|
+on :message, :object_action do |player, message|
   if (message.option == 1)
     object_id = message.id
     
     if (altar = PORTALS[object_id]) != nil # Get the altar associated with this exit portal.
       player.start_action(TeleportAction.new(player, altar.entrance_position, 1, altar.exit_position))
-      ctx.break_handler_chain
+      message.terminate
     elsif (rune = RUNES[object_id]) != nil # Get the rune associated with this altar.
       altar = CRAFTING_ALTARS[object_id]
       player.start_action(RunecraftingAction.new(player, rune, altar.crafting_centre))
-      ctx.break_handler_chain
+      message.terminate
     end
   end
 end

data/plugins/skill/runecraft/talisman.rb

@@ -30,11 +30,11 @@ def append_talisman(hash)
 end
 
 # Intercepts the item option message.
-on :message, :fourth_item_option do |ctx, player, message|
+on :message, :fourth_item_option do |player, message|
   talisman = TALISMANS[message.id]
   if (talisman != nil)
     player.send_message(talisman.get_message(player.position))
-    ctx.break_handler_chain
+    message.terminate
   end
 end
 

data/plugins/skill/runecraft/tiara.rb

@@ -62,7 +62,7 @@ on :login do |event, player|
 end
 
 # Intercepts the SecondObjectAction message to support left-click access to the altar when wielding the correct tiara.
-on :message, :second_object_action do |ctx, player, message|
+on :message, :second_object_action do |player, message|
   object_id = message.id
   tiara = TIARAS_BY_ALTAR[object_id]
   next if tiara.nil?
@@ -73,37 +73,37 @@ on :message, :second_object_action do |ctx, player, message|
     altar = ENTRANCE_ALTARS[tiara.altar]
     player.start_action(TeleportAction.new(player, message.position, 2, altar.entrance_position)) unless altar.nil?
 
-    ctx.break_handler_chain
+    message.terminate
   end
 end
 
 # Intercepts the SecondItemAction message to allow for config sending.
-on :message, :second_item_option do |ctx, player, message|
+on :message, :second_item_option do |player, message|
   tiara = TIARAS_BY_ID[message.id]
 
   unless tiara.nil?
     tiara.send_config(player)
-    ctx.break_handler_chain
+    message.terminate
   end
 end
 
 # Intercepts the FirstItemAction message to allow for config sending.
-on :message, :first_item_action do |ctx, player, message|
+on :message, :first_item_action do |player, message|
   tiara = TIARAS_BY_ID[message.id]
 
   unless tiara.nil?
     send_empty_config(player)
-    ctx.break_handler_chain
+    message.terminate
   end
 end
 
 # Intercepts the ItemOnObject message to create the tiara.
-on :message, :item_on_object do |ctx, player, message|
+on :message, :item_on_object do |player, message|
   tiara= TIARAS_BY_TALISMAN[message.id]; altar = CRAFTING_ALTARS[message.object_id]
   return if (tiara.nil? || altar.nil?)
 
   player.start_action(CreateTiaraAction.new(player, message.position, tiara, altar))
-  ctx.break_handler_chain
+  message.terminate
 end
 
 # An action lets the player create a tiara when it comes within the specified distance of a specified position.

data/plugins/util/intercept.rb

@@ -5,7 +5,7 @@
 # 
 # If you only wish to intercept a message, use the intercept method, e.g.
 #
-# intercept :item_on_item, used_id, target_id, :irreversible do |ctx, player, message|
+# intercept :item_on_item, used_id, target_id, :irreversible do |player, message|
 #   # code here
 # end
 

data/plugins/util/item-on-item-intercept.rb

@@ -36,11 +36,11 @@ class ItemOnItemPair
 
 end
 
-# Adds a message handler to the item on item message.
+# Adds a message listener to the item on item message.
-on :message, :item_on_item do |ctx, player, message|
+on :message, :item_on_item do |player, message|
   used, target = message.id, message.target_id
   pair = ItemOnItemPair.new(used, target)
   block = ITEM_PAIRS[pair]
 
-  block.call(ctx, player, message) unless block == nil
+  block.call(player, message) unless block == nil
 end

src/org/apollo/game/GamePulseHandler.java

@@ -35,8 +35,6 @@ public final class GamePulseHandler implements Runnable {
 			service.pulse();
 		} catch (Throwable reason) {
 			logger.log(Level.SEVERE, "Exception occured during pulse!", reason);
-		} finally {
-			service.shutdown(false);
 		}
 	}
 

src/org/apollo/game/GameService.java

@@ -10,13 +10,13 @@ import java.util.concurrent.ScheduledExecutorService;
 import java.util.concurrent.TimeUnit;
 
 import org.apollo.Service;
-import org.apollo.game.message.handler.MessageHandlerChainGroup;
+import org.apollo.game.message.MessageHandlerChainSet;
 import org.apollo.game.model.World;
 import org.apollo.game.model.World.RegistrationStatus;
 import org.apollo.game.model.area.Region;
 import org.apollo.game.model.entity.Player;
 import org.apollo.game.sync.ClientSynchronizer;
-import org.apollo.io.MessageHandlerChainParser;
+import org.apollo.io.MessageHandlerChainSetParser;
 import org.apollo.login.LoginService;
 import org.apollo.net.session.GameSession;
 import org.apollo.util.MobRepository;
@@ -39,9 +39,9 @@ public final class GameService extends Service {
 	private static final int UNREGISTERS_PER_CYCLE = 50;
 
 	/**
-	 * The {@link MessageHandlerChainGroup}.
+	 * The {@link MessageHandlerChainSet}.
 	 */
-	private MessageHandlerChainGroup chainGroup;
+	private MessageHandlerChainSet messageHandlerChainSet;
 
 	/**
 	 * A queue of players to remove.
@@ -51,8 +51,7 @@ public final class GameService extends Service {
 	/**
 	 * The scheduled executor service.
 	 */
-	private final ScheduledExecutorService scheduledExecutor = Executors.newSingleThreadScheduledExecutor(new NamedThreadFactory(
+	private final ScheduledExecutorService scheduledExecutor = Executors.newSingleThreadScheduledExecutor(new NamedThreadFactory("GameService"));
-			"GameService"));
 
 	/**
 	 * The {@link ClientSynchronizer}.
@@ -82,12 +81,12 @@ public final class GameService extends Service {
 	}
 
 	/**
-	 * Gets the message handler chains.
+	 * Gets the MessageHandlerChainSet
 	 * 
-	 * @return The message handler chains.
+	 * @return The set of MessageHandlerChain's.
 	 */
-	public MessageHandlerChainGroup getMessageHandlerChains() {
+	public MessageHandlerChainSet getMessageHandlerChainSet() {
-		return chainGroup;
+		return messageHandlerChainSet;
 	}
 
 	/**
@@ -101,7 +100,7 @@ public final class GameService extends Service {
 			for (Player player : players) {
 				GameSession session = player.getSession();
 				if (session != null) {
-					session.handlePendingMessages(chainGroup);
+					session.handlePendingMessages(messageHandlerChainSet);
 				}
 			}
 
@@ -143,8 +142,7 @@ public final class GameService extends Service {
 
 	@Override
 	public void start() {
-		scheduledExecutor.scheduleAtFixedRate(new GamePulseHandler(this), GameConstants.PULSE_DELAY, GameConstants.PULSE_DELAY,
+		scheduledExecutor.scheduleAtFixedRate(new GamePulseHandler(this), GameConstants.PULSE_DELAY, GameConstants.PULSE_DELAY, TimeUnit.MILLISECONDS);
-				TimeUnit.MILLISECONDS);
 	}
 
 	/**
@@ -181,8 +179,8 @@ public final class GameService extends Service {
 	 */
 	private void init() throws IOException, SAXException, ReflectiveOperationException {
 		try (InputStream input = new FileInputStream("data/messages.xml")) {
-			MessageHandlerChainParser chainGroupParser = new MessageHandlerChainParser(input);
+			MessageHandlerChainSetParser chainSetParser = new MessageHandlerChainSetParser(input);
-			chainGroup = chainGroupParser.parse(world);
+			messageHandlerChainSet = chainSetParser.parse(world);
 		}
 
 		try (InputStream input = new FileInputStream("data/synchronizer.xml")) {

src/org/apollo/game/message/Message.java

@@ -4,7 +4,29 @@ package org.apollo.game.message;
  * A message sent by the client that can be intercepted.
  * 
  * @author Graham
+ * @author Major
  */
 public abstract class Message {
 
+	/**
+	 * Indicates whether or not the Message chain has been terminated.
+	 */
+	private boolean terminated;
+
+	/**
+	 * Terminates the Message chain.
+	 */
+	public final void terminate() {
+		terminated = true;
+	}
+
+	/**
+	 * Returns whether or not the Message chain has been terminated.
+	 * 
+	 * @return {@code true} if the Message chain has been terminated, otherwise {@code false}.
+	 */
+	public final boolean terminated() {
+		return terminated;
+	}
+
 }

src/org/apollo/game/message/MessageHandler.java

@@ -1,14 +1,14 @@
-package org.apollo.game.message.handler;
+package org.apollo.game.message;
 
-import org.apollo.game.message.Message;
 import org.apollo.game.model.World;
 import org.apollo.game.model.entity.Player;
 
 /**
- * Handles messages received from the client.
+ * Listens for {@link Message}s received from the client.
  * 
  * @author Graham
- * @param <M> The type of message handled by this class.
+ * @author Ryley
+ * @param <M> The type of Message this class is listening for.
  */
 public abstract class MessageHandler<M extends Message> {
 
@@ -18,7 +18,7 @@ public abstract class MessageHandler<M extends Message> {
 	protected final World world;
 
 	/**
-	 * Creates the MessageHandler.
+	 * Creates the MessageListener.
 	 *
 	 * @param world The {@link World} the {@link Message} occurred in.
 	 */
@@ -27,12 +27,11 @@ public abstract class MessageHandler<M extends Message> {
 	}
 
 	/**
-	 * Handles a message.
+	 * Handles the Message that was received.
 	 * 
-	 * @param ctx The context.
+	 * @param player The player to handle the Message for.
-	 * @param player The player.
+	 * @param message The Message.
-	 * @param message The message.
 	 */
-	public abstract void handle(MessageHandlerContext ctx, Player player, M message);
+	public abstract void handle(Player player, M message);
 
 }

src/org/apollo/game/message/MessageHandlerChain.java

@@ -0,0 +1,72 @@
+package org.apollo.game.message;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.apollo.game.model.entity.Player;
+
+import com.google.common.base.MoreObjects;
+
+/**
+ * A chain of {@link MessageHandler}s
+ * 
+ * @author Graham
+ * @author Ryley
+ * @param <M> The Message type this chain represents.
+ */
+public final class MessageHandlerChain<M extends Message> {
+
+	/**
+	 * The handlers.
+	 */
+	private final List<MessageHandler<M>> handlers = new ArrayList<>();
+
+	/**
+	 * The Class type of this chain.
+	 */
+	private final Class<M> type;
+
+	/**
+	 * Constructs a new {@link MessageHandlerChain}.
+	 * 
+	 * @param type The Class type of this chain.
+	 */
+	public MessageHandlerChain(Class<M> type) {
+		this.type = type;
+	}
+
+	/**
+	 * Adds the specified {@link MessageHandler} to this chain.
+	 * 
+	 * @param handler The MessageHandler.
+	 */
+	public void addHandler(MessageHandler<M> handler) {
+		handlers.add(handler);
+	}
+
+	/**
+	 * Notifies each {@link MessageHandler} in this chain that a {@link Message} has been received.
+	 * 
+	 * @param player The Player to handle this message for.
+	 * @param message The Message.
+	 * @return {@code true} if and only if the Message propagated down the chain without being terminated, otherwise
+	 *         {@code false}.
+	 */
+	public boolean notify(Player player, M message) {
+		for (MessageHandler<M> handler : handlers) {
+			handler.handle(player, message);
+
+			if (message.terminated()) {
+				return false;
+			}
+		}
+
+		return true;
+	}
+
+	@Override
+	public String toString() {
+		return MoreObjects.toStringHelper(this).add("type", type).add("handlers", handlers).toString();
+	}
+
+}

src/org/apollo/game/message/MessageHandlerChainSet.java

@@ -0,0 +1,47 @@
+package org.apollo.game.message;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import org.apollo.game.model.entity.Player;
+
+/**
+ * A group of {@link MessageHandlerChain}s classified by the {@link Message} type.
+ * 
+ * @author Graham
+ * @author Ryley
+ * @author Major
+ */
+public final class MessageHandlerChainSet {
+
+	/**
+	 * The {@link Map} of Message types to {@link MessageHandlerChain}s
+	 */
+	private final Map<Class<? extends Message>, MessageHandlerChain<? extends Message>> chains = new HashMap<>();
+
+	/**
+	 * Notifies the appropriate {@link MessageHandlerChain} that a {@link Message} has been received.
+	 * 
+	 * @param message The Message.
+	 * @return {@code true} if the Message propagated down the chain without being terminated or if the chain for the
+	 *         Message was not found, otherwise {@code false}.
+	 */
+	public <M extends Message> boolean notify(Player player, M message) {
+		@SuppressWarnings("unchecked")
+		MessageHandlerChain<M> chain = (MessageHandlerChain<M>) chains.get(message.getClass());
+		return (chain == null) || chain.notify(player, message);
+	}
+
+	/**
+	 * Places the {@link MessageHandlerChain} into this set.
+	 * 
+	 * @param clazz The {@link Class} to associate the MessageHandlerChain with.
+	 * @param handler The MessageHandlerChain.
+	 */
+	@SuppressWarnings("unchecked")
+	public <M extends Message> void putHandler(Class<M> clazz, MessageHandler<? extends Message> handler) {
+		MessageHandlerChain<M> chain = (MessageHandlerChain<M>) chains.computeIfAbsent(clazz, MessageHandlerChain::new);
+		chain.addHandler((MessageHandler<M>) handler);
+	}
+
+}

src/org/apollo/game/message/handler/BankButtonMessageHandler.java

@@ -1,7 +1,6 @@
-package org.apollo.game.message.handler.impl;
+package org.apollo.game.message.handler;
 
-import org.apollo.game.message.handler.MessageHandler;
+import org.apollo.game.message.MessageHandler;
-import org.apollo.game.message.handler.MessageHandlerContext;
 import org.apollo.game.message.impl.ButtonMessage;
 import org.apollo.game.model.World;
 import org.apollo.game.model.entity.Player;
@@ -33,7 +32,7 @@ public final class BankButtonMessageHandler extends MessageHandler<ButtonMessage
 	private static final int WITHDRAW_AS_NOTE = 5386;
 
 	@Override
-	public void handle(MessageHandlerContext ctx, Player player, ButtonMessage message) {
+	public void handle(Player player, ButtonMessage message) {
 		if (message.getWidgetId() == WITHDRAW_AS_ITEM) {
 			player.setWithdrawingNotes(false);
 		} else if (message.getWidgetId() == WITHDRAW_AS_NOTE) {

src/org/apollo/game/message/handler/BankMessageHandler.java

@@ -1,7 +1,6 @@
-package org.apollo.game.message.handler.impl;
+package org.apollo.game.message.handler;
 
-import org.apollo.game.message.handler.MessageHandler;
+import org.apollo.game.message.MessageHandler;
-import org.apollo.game.message.handler.MessageHandlerContext;
 import org.apollo.game.message.impl.ItemActionMessage;
 import org.apollo.game.model.World;
 import org.apollo.game.model.entity.Player;
@@ -52,12 +51,12 @@ public final class BankMessageHandler extends MessageHandler<ItemActionMessage>
 	}
 
 	@Override
-	public void handle(MessageHandlerContext ctx, Player player, ItemActionMessage message) {
+	public void handle(Player player, ItemActionMessage message) {
 		if (player.getInterfaceSet().contains(BankConstants.BANK_WINDOW_ID)) {
 			if (message.getInterfaceId() == BankConstants.SIDEBAR_INVENTORY_ID) {
-				deposit(ctx, player, message);
+				deposit(player, message);
 			} else if (message.getInterfaceId() == BankConstants.BANK_INVENTORY_ID) {
-				withdraw(ctx, player, message);
+				withdraw(player, message);
 			}
 		}
 	}
@@ -65,36 +64,34 @@ public final class BankMessageHandler extends MessageHandler<ItemActionMessage>
 	/**
 	 * Handles a deposit action.
 	 * 
-	 * @param ctx The message handler context.
 	 * @param player The player.
 	 * @param message The message.
 	 */
-	private void deposit(MessageHandlerContext ctx, Player player, ItemActionMessage message) {
+	private void deposit(Player player, ItemActionMessage message) {
 		int amount = optionToAmount(message.getOption());
 
 		if (amount == -1) {
 			EnterAmountListener listener = new BankDepositEnterAmountListener(player, message.getSlot(), message.getId());
 			player.getInterfaceSet().openEnterAmountDialogue(listener);
 		} else if (!BankUtils.deposit(player, message.getSlot(), message.getId(), amount)) {
-			ctx.breakHandlerChain();
+			message.terminate();
 		}
 	}
 
 	/**
 	 * Handles a withdraw action.
 	 * 
-	 * @param ctx The message handler context.
 	 * @param player The player.
 	 * @param message The message.
 	 */
-	private void withdraw(MessageHandlerContext ctx, Player player, ItemActionMessage message) {
+	private void withdraw(Player player, ItemActionMessage message) {
 		int amount = optionToAmount(message.getOption());
 
 		if (amount == -1) {
 			EnterAmountListener listener = new BankWithdrawEnterAmountListener(player, message.getSlot(), message.getId());
 			player.getInterfaceSet().openEnterAmountDialogue(listener);
 		} else if (!BankUtils.withdraw(player, message.getSlot(), message.getId(), amount)) {
-			ctx.breakHandlerChain();
+			message.terminate();
 		}
 	}
 

src/org/apollo/game/message/handler/ChatMessageHandler.java

@@ -1,7 +1,6 @@
-package org.apollo.game.message.handler.impl;
+package org.apollo.game.message.handler;
 
-import org.apollo.game.message.handler.MessageHandler;
+import org.apollo.game.message.MessageHandler;
-import org.apollo.game.message.handler.MessageHandlerContext;
 import org.apollo.game.message.impl.ChatMessage;
 import org.apollo.game.model.World;
 import org.apollo.game.model.entity.Player;
@@ -24,7 +23,7 @@ public final class ChatMessageHandler extends MessageHandler<ChatMessage> {
 	}
 
 	@Override
-	public void handle(MessageHandlerContext ctx, Player player, ChatMessage message) {
+	public void handle(Player player, ChatMessage message) {
 		player.getBlockSet().add(SynchronizationBlock.createChatBlock(player, message));
 	}
 

src/org/apollo/game/message/handler/ChatVerificationHandler.java

@@ -1,7 +1,6 @@
-package org.apollo.game.message.handler.impl;
+package org.apollo.game.message.handler;
 
-import org.apollo.game.message.handler.MessageHandler;
+import org.apollo.game.message.MessageHandler;
-import org.apollo.game.message.handler.MessageHandlerContext;
 import org.apollo.game.message.impl.ChatMessage;
 import org.apollo.game.model.World;
 import org.apollo.game.model.entity.Player;
@@ -23,11 +22,11 @@ public final class ChatVerificationHandler extends MessageHandler<ChatMessage> {
 	}
 
 	@Override
-	public void handle(MessageHandlerContext ctx, Player player, ChatMessage message) {
+	public void handle(Player player, ChatMessage message) {
 		int color = message.getTextColor();
 		int effects = message.getTextEffects();
 		if (color < 0 || color > 11 || effects < 0 || effects > 5) {
-			ctx.breakHandlerChain();
+			message.terminate();
 		}
 	}
 

src/org/apollo/game/message/handler/ClosedInterfaceMessageHandler.java

@@ -1,7 +1,6 @@
-package org.apollo.game.message.handler.impl;
+package org.apollo.game.message.handler;
 
-import org.apollo.game.message.handler.MessageHandler;
+import org.apollo.game.message.MessageHandler;
-import org.apollo.game.message.handler.MessageHandlerContext;
 import org.apollo.game.message.impl.ClosedInterfaceMessage;
 import org.apollo.game.model.World;
 import org.apollo.game.model.entity.Player;
@@ -23,7 +22,7 @@ public final class ClosedInterfaceMessageHandler extends MessageHandler<ClosedIn
 	}
 
 	@Override
-	public void handle(MessageHandlerContext ctx, Player player, ClosedInterfaceMessage message) {
+	public void handle(Player player, ClosedInterfaceMessage message) {
 		player.getInterfaceSet().interfaceClosed();
 	}
 

src/org/apollo/game/message/handler/CommandMessageHandler.java

@@ -1,9 +1,8 @@
-package org.apollo.game.message.handler.impl;
+package org.apollo.game.message.handler;
 
 import org.apollo.game.command.Command;
 import org.apollo.game.message.Message;
-import org.apollo.game.message.handler.MessageHandler;
+import org.apollo.game.message.MessageHandler;
-import org.apollo.game.message.handler.MessageHandlerContext;
 import org.apollo.game.message.impl.CommandMessage;
 import org.apollo.game.model.World;
 import org.apollo.game.model.entity.Player;
@@ -25,7 +24,7 @@ public final class CommandMessageHandler extends MessageHandler<CommandMessage>
 	}
 
 	@Override
-	public void handle(MessageHandlerContext ctx, Player player, CommandMessage message) {
+	public void handle(Player player, CommandMessage message) {
 		String[] components = message.getCommand().split(" ");
 		String name = components[0];
 

src/org/apollo/game/message/handler/DialogueButtonHandler.java

@@ -1,7 +1,6 @@
-package org.apollo.game.message.handler.impl;
+package org.apollo.game.message.handler;
 
-import org.apollo.game.message.handler.MessageHandler;
+import org.apollo.game.message.MessageHandler;
-import org.apollo.game.message.handler.MessageHandlerContext;
 import org.apollo.game.message.impl.ButtonMessage;
 import org.apollo.game.model.World;
 import org.apollo.game.model.entity.Player;
@@ -25,12 +24,12 @@ public final class DialogueButtonHandler extends MessageHandler<ButtonMessage> {
 	}
 
 	@Override
-	public void handle(MessageHandlerContext ctx, Player player, ButtonMessage message) {
+	public void handle(Player player, ButtonMessage message) {
 		if (player.getInterfaceSet().contains(InterfaceType.DIALOGUE)) {
 			boolean terminate = player.getInterfaceSet().buttonClicked(message.getWidgetId());
 
 			if (terminate) {
-				ctx.breakHandlerChain();
+				message.terminate();
 			}
 		}
 	}

src/org/apollo/game/message/handler/DialogueContinueMessageHandler.java

@@ -1,7 +1,6 @@
-package org.apollo.game.message.handler.impl;
+package org.apollo.game.message.handler;
 
-import org.apollo.game.message.handler.MessageHandler;
+import org.apollo.game.message.MessageHandler;
-import org.apollo.game.message.handler.MessageHandlerContext;
 import org.apollo.game.message.impl.DialogueContinueMessage;
 import org.apollo.game.model.World;
 import org.apollo.game.model.entity.Player;
@@ -24,7 +23,7 @@ public final class DialogueContinueMessageHandler extends MessageHandler<Dialogu
 	}
 
 	@Override
-	public void handle(MessageHandlerContext ctx, Player player, DialogueContinueMessage message) {
+	public void handle(Player player, DialogueContinueMessage message) {
 		if (player.getInterfaceSet().contains(InterfaceType.DIALOGUE)) {
 			player.getInterfaceSet().continueRequested();
 		}

src/org/apollo/game/message/handler/EnteredAmountMessageHandler.java

@@ -1,7 +1,6 @@
-package org.apollo.game.message.handler.impl;
+package org.apollo.game.message.handler;
 
-import org.apollo.game.message.handler.MessageHandler;
+import org.apollo.game.message.MessageHandler;
-import org.apollo.game.message.handler.MessageHandlerContext;
 import org.apollo.game.message.impl.EnteredAmountMessage;
 import org.apollo.game.model.World;
 import org.apollo.game.model.entity.Player;
@@ -23,7 +22,7 @@ public final class EnteredAmountMessageHandler extends MessageHandler<EnteredAmo
 	}
 
 	@Override
-	public void handle(MessageHandlerContext ctx, Player player, EnteredAmountMessage message) {
+	public void handle(Player player, EnteredAmountMessage message) {
 		player.getInterfaceSet().enteredAmount(message.getAmount());
 	}
 

src/org/apollo/game/message/handler/EquipItemHandler.java

@@ -1,7 +1,6 @@
-package org.apollo.game.message.handler.impl;
+package org.apollo.game.message.handler;
 
-import org.apollo.game.message.handler.MessageHandler;
+import org.apollo.game.message.MessageHandler;
-import org.apollo.game.message.handler.MessageHandlerContext;
 import org.apollo.game.message.impl.ItemOptionMessage;
 import org.apollo.game.model.Item;
 import org.apollo.game.model.World;
@@ -37,7 +36,7 @@ public final class EquipItemHandler extends MessageHandler<ItemOptionMessage> {
 	}
 
 	@Override
-	public void handle(MessageHandlerContext ctx, Player player, ItemOptionMessage message) {
+	public void handle(Player player, ItemOptionMessage message) {
 		if (message.getOption() != EQUIP_OPTION || message.getInterfaceId() != SynchronizationInventoryListener.INVENTORY_ID) {
 			return;
 		}
@@ -60,7 +59,7 @@ public final class EquipItemHandler extends MessageHandler<ItemOptionMessage> {
 				String article = LanguageUtil.getIndefiniteArticle(name);
 
 				player.sendMessage("You need " + article + " " + name + " level of " + requirement + " to equip this item.");
-				ctx.breakHandlerChain();
+				message.terminate();
 				return;
 			}
 		}
@@ -78,7 +77,7 @@ public final class EquipItemHandler extends MessageHandler<ItemOptionMessage> {
 		if (definition.isTwoHanded()) {
 			int slotsRequired = weapon != null && shield != null ? 1 : 0;
 			if (inventory.freeSlots() < slotsRequired) {
-				ctx.breakHandlerChain();
+				message.terminate();
 				return;
 			}
 

src/org/apollo/game/message/handler/ItemOnItemVerificationHandler.java

@@ -1,7 +1,6 @@
-package org.apollo.game.message.handler.impl;
+package org.apollo.game.message.handler;
 
-import org.apollo.game.message.handler.MessageHandler;
+import org.apollo.game.message.MessageHandler;
-import org.apollo.game.message.handler.MessageHandlerContext;
 import org.apollo.game.message.impl.ItemOnItemMessage;
 import org.apollo.game.model.Item;
 import org.apollo.game.model.World;
@@ -27,7 +26,7 @@ public final class ItemOnItemVerificationHandler extends MessageHandler<ItemOnIt
 	}
 
 	@Override
-	public void handle(MessageHandlerContext ctx, Player player, ItemOnItemMessage message) {
+	public void handle(Player player, ItemOnItemMessage message) {
 		Inventory inventory;
 
 		switch (message.getInterfaceId()) {
@@ -42,19 +41,19 @@ public final class ItemOnItemVerificationHandler extends MessageHandler<ItemOnIt
 				inventory = player.getBank();
 				break;
 			default:
-				ctx.breakHandlerChain();
+				message.terminate();
 				return;
 		}
 
 		int slot = message.getTargetSlot();
 		if (slot < 0 || slot >= inventory.capacity()) {
-			ctx.breakHandlerChain();
+			message.terminate();
 			return;
 		}
 
 		Item item = inventory.get(slot);
 		if (item == null || item.getId() != message.getTargetId()) {
-			ctx.breakHandlerChain();
+			message.terminate();
 		}
 	}
 

src/org/apollo/game/message/handler/ItemOnObjectVerificationHandler.java

@@ -1,7 +1,6 @@
-package org.apollo.game.message.handler.impl;
+package org.apollo.game.message.handler;
 
-import org.apollo.game.message.handler.MessageHandler;
+import org.apollo.game.message.MessageHandler;
-import org.apollo.game.message.handler.MessageHandlerContext;
 import org.apollo.game.message.impl.ItemOnObjectMessage;
 import org.apollo.game.model.Item;
 import org.apollo.game.model.World;
@@ -27,10 +26,10 @@ public final class ItemOnObjectVerificationHandler extends MessageHandler<ItemOn
 	}
 
 	@Override
-	public void handle(MessageHandlerContext ctx, Player player, ItemOnObjectMessage message) {
+	public void handle(Player player, ItemOnObjectMessage message) {
 		if (message.getInterfaceId() != SynchronizationInventoryListener.INVENTORY_ID
 				&& message.getInterfaceId() != BankConstants.SIDEBAR_INVENTORY_ID) {
-			ctx.breakHandlerChain();
+			message.terminate();
 			return;
 		}
 
@@ -38,13 +37,13 @@ public final class ItemOnObjectVerificationHandler extends MessageHandler<ItemOn
 
 		int slot = message.getSlot();
 		if (slot < 0 || slot >= inventory.capacity()) {
-			ctx.breakHandlerChain();
+			message.terminate();
 			return;
 		}
 
 		Item item = inventory.get(slot);
 		if (item == null || item.getId() != message.getId()) {
-			ctx.breakHandlerChain();
+			message.terminate();
 			return;
 		}
 	}

src/org/apollo/game/message/handler/ItemVerificationHandler.java

@@ -1,10 +1,9 @@
-package org.apollo.game.message.handler.impl;
+package org.apollo.game.message.handler;
 
 import java.util.HashMap;
 import java.util.Map;
 
-import org.apollo.game.message.handler.MessageHandler;
+import org.apollo.game.message.MessageHandler;
-import org.apollo.game.message.handler.MessageHandlerContext;
 import org.apollo.game.message.impl.InventoryItemMessage;
 import org.apollo.game.model.Item;
 import org.apollo.game.model.World;
@@ -72,10 +71,10 @@ public final class ItemVerificationHandler extends MessageHandler<InventoryItemM
 	}
 
 	@Override
-	public void handle(MessageHandlerContext ctx, Player player, InventoryItemMessage message) {
+	public void handle(Player player, InventoryItemMessage message) {
 		InventorySupplier supplier = inventories.get(message.getInterfaceId());
 		if (supplier == null) {
-			ctx.breakHandlerChain();
+			message.terminate();
 			return;
 		}
 
@@ -83,13 +82,13 @@ public final class ItemVerificationHandler extends MessageHandler<InventoryItemM
 
 		int slot = message.getSlot();
 		if (slot < 0 || slot >= inventory.capacity()) {
-			ctx.breakHandlerChain();
+			message.terminate();
 			return;
 		}
 
 		Item item = inventory.get(slot);
 		if (item == null || item.getId() != message.getId()) {
-			ctx.breakHandlerChain();
+			message.terminate();
 		}
 	}
 

src/org/apollo/game/message/handler/MessageHandlerChain.java

@@ -1,62 +0,0 @@
-package org.apollo.game.message.handler;
-
-import java.util.ArrayDeque;
-import java.util.Arrays;
-import java.util.Deque;
-
-import org.apollo.game.message.Message;
-import org.apollo.game.model.entity.Player;
-
-/**
- * A chain of message handlers.
- * 
- * @author Graham
- * @author Ryley
- * @param <M> The type of message handled by this chain.
- */
-public final class MessageHandlerChain<M extends Message> {
-
-	/**
-	 * The handlers.
-	 */
-	private final Deque<MessageHandler<M>> handlers;
-
-	/**
-	 * Creates the message handler chain.
-	 * 
-	 * @param handlers The handlers.
-	 */
-	@SafeVarargs
-	public MessageHandlerChain(MessageHandler<M>... handlers) {
-		this.handlers = new ArrayDeque<>(Arrays.asList(handlers));
-	}
-
-	/**
-	 * Dynamically adds a message handler to the end of the chain.
-	 * 
-	 * @param handler The handler.
-	 */
-	public void addLast(MessageHandler<M> handler) {
-		handlers.addLast(handler);
-	}
-
-	/**
-	 * Handles the message, passing it down the chain until the chain is broken or the message reaches the end of the
-	 * chain.
-	 * 
-	 * @param player The player.
-	 * @param message The message.
-	 */
-	public void handle(Player player, M message) {
-		MessageHandlerContext context = new MessageHandlerContext();
-
-		for (MessageHandler<M> handler : handlers) {
-			handler.handle(context, player, message);
-
-			if (context.isBroken()) {
-				break;
-			}
-		}
-	}
-
-}

src/org/apollo/game/message/handler/MessageHandlerChainGroup.java

@@ -1,49 +0,0 @@
-package org.apollo.game.message.handler;
-
-import java.util.Map;
-
-import org.apollo.game.message.Message;
-
-/**
- * A group of {@link MessageHandlerChain}s classified by the {@link Message} type.
- * 
- * @author Graham
- */
-public final class MessageHandlerChainGroup {
-
-	/**
-	 * The map of message classes to message handler chains.
-	 */
-	private final Map<Class<? extends Message>, MessageHandlerChain<?>> chains;
-
-	/**
-	 * Creates the message handler chain group.
-	 * 
-	 * @param chains The chains map.
-	 */
-	public MessageHandlerChainGroup(Map<Class<? extends Message>, MessageHandlerChain<?>> chains) {
-		this.chains = chains;
-	}
-
-	/**
-	 * Gets a {@link MessageHandlerChain} from this group.
-	 * 
-	 * @param clazz The message class.
-	 * @return The {@link MessageHandlerChain} if one was found, {@code null} otherwise.
-	 */
-	@SuppressWarnings("unchecked")
-	public <M extends Message> MessageHandlerChain<M> getChain(Class<M> clazz) {
-		return (MessageHandlerChain<M>) chains.get(clazz);
-	}
-
-	/**
-	 * Registers a {@link MessageHandlerChain} associated with the specified {@link Class} to this group.
-	 * 
-	 * @param clazz The message class.
-	 * @param chain The message handler chain.
-	 */
-	public <M extends Message> void register(Class<M> clazz, MessageHandlerChain<M> chain) {
-		chains.put(clazz, chain);
-	}
-
-}

src/org/apollo/game/message/handler/MessageHandlerContext.java

@@ -1,32 +0,0 @@
-package org.apollo.game.message.handler;
-
-/**
- * Provides operations specific to a {@link MessageHandler} in a {@link MessageHandlerChain}.
- * 
- * @author Graham
- * @author Ryley
- */
-public final class MessageHandlerContext {
-
-	/**
-	 * Denotes whether or not this handler chain is broken.
-	 */
-	private boolean broken;
-
-	/**
-	 * Breaks the handler chain.
-	 */
-	public void breakHandlerChain() {
-		broken = true;
-	}
-
-	/**
-	 * Returns whether or not this handler chain is broken.
-	 * 
-	 * @return {@code true} if this handler chain is broken, otherwise {@code false}.
-	 */
-	public boolean isBroken() {
-		return broken;
-	}
-
-}

src/org/apollo/game/message/handler/NpcActionVerificationHandler.java

@@ -1,7 +1,6 @@
-package org.apollo.game.message.handler.impl;
+package org.apollo.game.message.handler;
 
-import org.apollo.game.message.handler.MessageHandler;
+import org.apollo.game.message.MessageHandler;
-import org.apollo.game.message.handler.MessageHandlerContext;
 import org.apollo.game.message.impl.NpcActionMessage;
 import org.apollo.game.model.World;
 import org.apollo.game.model.def.NpcDefinition;
@@ -27,12 +26,12 @@ public final class NpcActionVerificationHandler extends MessageHandler<NpcAction
 	}
 
 	@Override
-	public void handle(MessageHandlerContext ctx, Player player, NpcActionMessage message) {
+	public void handle(Player player, NpcActionMessage message) {
 		int index = message.getIndex();
 		MobRepository<Npc> repository = world.getNpcRepository();
 
 		if (index < 0 || index >= repository.capacity()) {
-			ctx.breakHandlerChain();
+			message.terminate();
 			return;
 		}
 
@@ -40,13 +39,13 @@ public final class NpcActionVerificationHandler extends MessageHandler<NpcAction
 
 		if (npc == null || !player.getPosition().isWithinDistance(npc.getPosition(), player.getViewingDistance() + 1)) {
 			// +1 in case it was decremented after the player clicked the action.
-			ctx.breakHandlerChain();
+			message.terminate();
 			return;
 		}
 
 		NpcDefinition definition = npc.getDefinition();
 		if (message.getOption() >= definition.getInteractions().length) {
-			ctx.breakHandlerChain();
+			message.terminate();
 			return;
 		}
 	}

src/org/apollo/game/message/handler/ObjectActionVerificationHandler.java

@@ -1,10 +1,9 @@
-package org.apollo.game.message.handler.impl;
+package org.apollo.game.message.handler;
 
 import java.util.List;
 import java.util.Set;
 
-import org.apollo.game.message.handler.MessageHandler;
+import org.apollo.game.message.MessageHandler;
-import org.apollo.game.message.handler.MessageHandlerContext;
 import org.apollo.game.message.impl.ObjectActionMessage;
 import org.apollo.game.model.Position;
 import org.apollo.game.model.World;
@@ -42,10 +41,10 @@ public final class ObjectActionVerificationHandler extends MessageHandler<Object
 	}
 
 	@Override
-	public void handle(MessageHandlerContext ctx, Player player, ObjectActionMessage message) {
+	public void handle(Player player, ObjectActionMessage message) {
 		int id = message.getId();
 		if (id < 0 || id >= ObjectDefinition.count()) {
-			ctx.breakHandlerChain();
+			message.terminate();
 			return;
 		}
 
@@ -54,13 +53,13 @@ public final class ObjectActionVerificationHandler extends MessageHandler<Object
 		Set<GameObject> objects = region.getEntities(position, EntityType.STATIC_OBJECT, EntityType.DYNAMIC_OBJECT);
 
 		if (!player.getPosition().isWithinDistance(position, 15) || !containsObject(id, objects)) {
-			ctx.breakHandlerChain();
+			message.terminate();
 			return;
 		}
 
 		ObjectDefinition definition = ObjectDefinition.lookup(id);
 		if (message.getOption() >= definition.getMenuActions().length) {
-			ctx.breakHandlerChain();
+			message.terminate();
 			return;
 		}
 	}

src/org/apollo/game/message/handler/PlayerActionVerificationHandler.java

@@ -1,7 +1,6 @@
-package org.apollo.game.message.handler.impl;
+package org.apollo.game.message.handler;
 
-import org.apollo.game.message.handler.MessageHandler;
+import org.apollo.game.message.MessageHandler;
-import org.apollo.game.message.handler.MessageHandlerContext;
 import org.apollo.game.message.impl.PlayerActionMessage;
 import org.apollo.game.model.World;
 import org.apollo.game.model.entity.Player;
@@ -24,19 +23,19 @@ public final class PlayerActionVerificationHandler extends MessageHandler<Player
 	}
 
 	@Override
-	public void handle(MessageHandlerContext ctx, Player player, PlayerActionMessage message) {
+	public void handle(Player player, PlayerActionMessage message) {
 		int index = message.getIndex();
 		MobRepository<Player> repository = world.getPlayerRepository();
 
 		if (index < 0 || index >= repository.capacity()) {
-			ctx.breakHandlerChain();
+			message.terminate();
 			return;
 		}
 
 		Player other = repository.get(index);
 		if (other == null || !player.getPosition().isWithinDistance(other.getPosition(), player.getViewingDistance() + 1)) {
 			// +1 in case it was decremented after the player clicked the action.
-			ctx.breakHandlerChain();
+			message.terminate();
 			return;
 		}
 	}

src/org/apollo/game/message/handler/PlayerDesignMessageHandler.java

@@ -1,7 +1,6 @@
-package org.apollo.game.message.handler.impl;
+package org.apollo.game.message.handler;
 
-import org.apollo.game.message.handler.MessageHandler;
+import org.apollo.game.message.MessageHandler;
-import org.apollo.game.message.handler.MessageHandlerContext;
 import org.apollo.game.message.impl.CloseInterfaceMessage;
 import org.apollo.game.message.impl.PlayerDesignMessage;
 import org.apollo.game.model.World;
@@ -24,7 +23,7 @@ public final class PlayerDesignMessageHandler extends MessageHandler<PlayerDesig
 	}
 
 	@Override
-	public void handle(MessageHandlerContext ctx, Player player, PlayerDesignMessage message) {
+	public void handle(Player player, PlayerDesignMessage message) {
 		player.setAppearance(message.getAppearance());
 		player.send(new CloseInterfaceMessage());
 	}

src/org/apollo/game/message/handler/PlayerDesignVerificationHandler.java

@@ -1,7 +1,6 @@
-package org.apollo.game.message.handler.impl;
+package org.apollo.game.message.handler;
 
-import org.apollo.game.message.handler.MessageHandler;
+import org.apollo.game.message.MessageHandler;
-import org.apollo.game.message.handler.MessageHandlerContext;
 import org.apollo.game.message.impl.PlayerDesignMessage;
 import org.apollo.game.model.Appearance;
 import org.apollo.game.model.World;
@@ -25,9 +24,9 @@ public final class PlayerDesignVerificationHandler extends MessageHandler<Player
 	}
 
 	@Override
-	public void handle(MessageHandlerContext ctx, Player player, PlayerDesignMessage message) {
+	public void handle(Player player, PlayerDesignMessage message) {
 		if (!valid(message.getAppearance())) {
-			ctx.breakHandlerChain();
+			message.terminate();
 		}
 	}
 

src/org/apollo/game/message/handler/RemoveEquippedItemHandler.java

@@ -1,7 +1,6 @@
-package org.apollo.game.message.handler.impl;
+package org.apollo.game.message.handler;
 
-import org.apollo.game.message.handler.MessageHandler;
+import org.apollo.game.message.MessageHandler;
-import org.apollo.game.message.handler.MessageHandlerContext;
 import org.apollo.game.message.impl.ItemActionMessage;
 import org.apollo.game.model.Item;
 import org.apollo.game.model.World;
@@ -27,7 +26,7 @@ public final class RemoveEquippedItemHandler extends MessageHandler<ItemActionMe
 	}
 
 	@Override
-	public void handle(MessageHandlerContext ctx, Player player, ItemActionMessage message) {
+	public void handle(Player player, ItemActionMessage message) {
 		if (message.getOption() == 1 && message.getInterfaceId() == SynchronizationInventoryListener.EQUIPMENT_ID) {
 			Inventory inventory = player.getInventory();
 			Inventory equipment = player.getEquipment();
@@ -38,7 +37,7 @@ public final class RemoveEquippedItemHandler extends MessageHandler<ItemActionMe
 
 			if (inventory.freeSlots() == 0 && !item.getDefinition().isStackable()) {
 				inventory.forceCapacityExceeded();
-				ctx.breakHandlerChain();
+				message.terminate();
 				return;
 			}
 

src/org/apollo/game/message/handler/SwitchItemMessageHandler.java

@@ -1,7 +1,6 @@
-package org.apollo.game.message.handler.impl;
+package org.apollo.game.message.handler;
 
-import org.apollo.game.message.handler.MessageHandler;
+import org.apollo.game.message.MessageHandler;
-import org.apollo.game.message.handler.MessageHandlerContext;
 import org.apollo.game.message.impl.SwitchItemMessage;
 import org.apollo.game.model.World;
 import org.apollo.game.model.entity.Player;
@@ -27,7 +26,7 @@ public final class SwitchItemMessageHandler extends MessageHandler<SwitchItemMes
 	}
 
 	@Override
-	public void handle(MessageHandlerContext ctx, Player player, SwitchItemMessage message) {
+	public void handle(Player player, SwitchItemMessage message) {
 		Inventory inventory;
 		boolean insertPermitted = false;
 

src/org/apollo/game/message/handler/WalkMessageHandler.java

@@ -1,7 +1,6 @@
-package org.apollo.game.message.handler.impl;
+package org.apollo.game.message.handler;
 
-import org.apollo.game.message.handler.MessageHandler;
+import org.apollo.game.message.MessageHandler;
-import org.apollo.game.message.handler.MessageHandlerContext;
 import org.apollo.game.message.impl.WalkMessage;
 import org.apollo.game.model.Position;
 import org.apollo.game.model.World;
@@ -25,7 +24,7 @@ public final class WalkMessageHandler extends MessageHandler<WalkMessage> {
 	}
 
 	@Override
-	public void handle(MessageHandlerContext ctx, Player player, WalkMessage message) {
+	public void handle(Player player, WalkMessage message) {
 		WalkingQueue queue = player.getWalkingQueue();
 
 		Position[] steps = message.getSteps();

src/org/apollo/game/message/handler/impl/package-info.java

@@ -1,4 +0,0 @@
-/**
- * Contains message handler implementations.
- */
-package org.apollo.game.message.handler.impl;

src/org/apollo/game/message/handler/package-info.java

@@ -1,4 +1,4 @@
 /**
- * Contains the base classes for message handling.
+ * Contains message handler implementations.
  */
 package org.apollo.game.message.handler;

src/org/apollo/game/model/entity/Player.java

@@ -46,6 +46,7 @@ import org.apollo.game.model.skill.SynchronizationSkillListener;
 import org.apollo.game.sync.block.SynchronizationBlock;
 import org.apollo.net.session.GameSession;
 import org.apollo.security.PlayerCredentials;
+import org.apollo.util.CollectionUtil;
 import org.apollo.util.Point;
 
 import com.google.common.base.MoreObjects;
@@ -668,17 +669,16 @@ public final class Player extends Mob {
 	 * @param message The message..
 	 */
 	public void send(Message message) {
-		if (isActive()) {
+		if (!isActive()) {
-			if (!queuedMessages.isEmpty()) {
-				for (Message queuedMessage : queuedMessages) {
-					session.dispatchMessage(queuedMessage);
-				}
-				queuedMessages.clear();
-			}
-			session.dispatchMessage(message);
-		} else {
 			queuedMessages.add(message);
+			return;
 		}
+
+		if (!queuedMessages.isEmpty()) {
+			CollectionUtil.pollAll(queuedMessages, session::dispatchMessage);
+		}
+
+		session.dispatchMessage(message);
 	}
 
 	/**

src/org/apollo/game/model/event/EventListenerChain.java

@@ -63,4 +63,5 @@ final class EventListenerChain<E extends Event> {
 	public String toString() {
 		return MoreObjects.toStringHelper(this).add("type", type).add("listeners", listeners).toString();
 	}
+
 }

src/org/apollo/game/model/inter/InterfaceSet.java

@@ -4,6 +4,7 @@ import java.util.HashMap;
 import java.util.Map;
 import java.util.Optional;
 
+import org.apollo.game.message.MessageHandlerChain;
 import org.apollo.game.message.impl.CloseInterfaceMessage;
 import org.apollo.game.message.impl.EnterAmountMessage;
 import org.apollo.game.message.impl.OpenDialogueInterfaceMessage;
@@ -75,7 +76,7 @@ public final class InterfaceSet {
 	 * Called when the player has clicked the specified button. Notifies the current dialogue listener.
 	 * 
 	 * @param button The button.
-	 * @return {@code true} if the message handler chain should be broken.
+	 * @return {@code true} if the {@link MessageHandlerChain} should be broken.
 	 */
 	public boolean buttonClicked(int button) {
 		return dialogueListener.isPresent() && dialogueListener.get().buttonClicked(button);

src/org/apollo/game/model/inter/dialogue/DialogueListener.java

@@ -1,5 +1,6 @@
 package org.apollo.game.model.inter.dialogue;
 
+import org.apollo.game.message.MessageHandlerChain;
 import org.apollo.game.model.inter.InterfaceListener;
 
 /**
@@ -17,7 +18,7 @@ public interface DialogueListener extends InterfaceListener {
 	 * </p>
 	 * 
 	 * @param button The button interface id.
-	 * @return {@code true} if the message handler chain should be broken, {@code false} if it should be continued.
+	 * @return {@code true} if the {@link MessageHandlerChain} should be broken, {@code false} if it should be continued.
 	 */
 	public boolean buttonClicked(int button);
 

src/org/apollo/game/scheduling/Scheduler.java

@@ -6,6 +6,8 @@ import java.util.Iterator;
 import java.util.List;
 import java.util.Queue;
 
+import org.apollo.util.CollectionUtil;
+
 /**
  * A class which manages {@link ScheduledTask}s.
  * 
@@ -14,29 +16,26 @@ import java.util.Queue;
 public final class Scheduler {
 
 	/**
-	 * A queue of new tasks that should be added.
+	 * An {@link ArrayDeque} of tasks that are pending execution.
 	 */
-	private Queue<ScheduledTask> newTasks = new ArrayDeque<>();
+	private final Queue<ScheduledTask> pendingTasks = new ArrayDeque<>();
 
 	/**
-	 * A list of currently active tasks.
+	 * An {@link ArrayList} of currently active tasks.
 	 */
-	private List<ScheduledTask> tasks = new ArrayList<>();
+	private final List<ScheduledTask> tasks = new ArrayList<>();
 
 	/**
 	 * Called every pulse: executes tasks that are still pending, adds new tasks and stops old tasks.
 	 */
 	public void pulse() {
-		ScheduledTask task;
+		CollectionUtil.pollAll(pendingTasks, tasks::add);
-		while ((task = newTasks.poll()) != null) {
-			tasks.add(task);
-		}
 
-		for (Iterator<ScheduledTask> it = tasks.iterator(); it.hasNext();) {
+		for (Iterator<ScheduledTask> iterator = tasks.iterator(); iterator.hasNext();) {
-			task = it.next();
+			ScheduledTask task = iterator.next();
 			task.pulse();
-			if (!task.isRunning()) {
+			if (task.isRunning()) {
-				it.remove();
+				iterator.remove();
 			}
 		}
 	}
@@ -48,7 +47,7 @@ public final class Scheduler {
 	 * @return {@code true} if the task was added successfully.
 	 */
 	public boolean schedule(ScheduledTask task) {
-		return newTasks.add(task);
+		return pendingTasks.add(task);
 	}
 
 }

src/org/apollo/io/MessageHandlerChainSetParser.java

@@ -2,26 +2,22 @@ package org.apollo.io;
 
 import java.io.IOException;
 import java.io.InputStream;
-import java.util.ArrayList;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
 
 import org.apollo.game.message.Message;
-import org.apollo.game.message.handler.MessageHandler;
+import org.apollo.game.message.MessageHandler;
-import org.apollo.game.message.handler.MessageHandlerChain;
+import org.apollo.game.message.MessageHandlerChain;
-import org.apollo.game.message.handler.MessageHandlerChainGroup;
+import org.apollo.game.message.MessageHandlerChainSet;
 import org.apollo.game.model.World;
 import org.apollo.util.xml.XmlNode;
 import org.apollo.util.xml.XmlParser;
 import org.xml.sax.SAXException;
 
 /**
- * A class that parses the {@code messages.xml} file to produce {@link MessageHandlerChainGroup}s.
+ * A class that parses the {@code messages.xml} file to produce {@link MessageHandlerChainSet}s.
  * 
  * @author Graham
  */
-public final class MessageHandlerChainParser {
+public final class MessageHandlerChainSetParser {
 
 	/**
 	 * The source {@link InputStream}.
@@ -39,7 +35,7 @@ public final class MessageHandlerChainParser {
 	 * @param is The source {@link InputStream}.
 	 * @throws SAXException If a SAX error occurs.
 	 */
-	public MessageHandlerChainParser(InputStream is) throws SAXException {
+	public MessageHandlerChainSetParser(InputStream is) throws SAXException {
 		this.is = is;
 	}
 
@@ -47,18 +43,18 @@ public final class MessageHandlerChainParser {
 	 * Parses the XML and produces a group of {@link MessageHandlerChain}s.
 	 * 
 	 * @param world The {@link World} this MessageHandlerChainGroup is for.
-	 * @return A {@link MessageHandlerChainGroup}.
+	 * @return A {@link MessageHandlerChainSet}.
 	 * @throws IOException If an I/O error occurs.
 	 * @throws SAXException If a SAX error occurs.
 	 * @throws ReflectiveOperationException If a reflection error occurs.
 	 */
-	public MessageHandlerChainGroup parse(World world) throws IOException, SAXException, ReflectiveOperationException {
+	public MessageHandlerChainSet parse(World world) throws IOException, SAXException, ReflectiveOperationException {
 		XmlNode messages = parser.parse(is);
 		if (!messages.getName().equals("messages")) {
 			throw new IOException("Root node name is not 'messages'.");
 		}
 
-		Map<Class<? extends Message>, MessageHandlerChain<?>> chains = new HashMap<>();
+		MessageHandlerChainSet chainSet = new MessageHandlerChainSet();
 
 		for (XmlNode message : messages) {
 			if (!message.getName().equals("message")) {
@@ -81,7 +77,6 @@ public final class MessageHandlerChainParser {
 
 			@SuppressWarnings("unchecked")
 			Class<? extends Message> messageClass = (Class<? extends Message>) Class.forName(messageClassName);
-			List<MessageHandler<?>> handlers = new ArrayList<>();
 
 			for (XmlNode handlerNode : chainNode) {
 				if (!handlerNode.getName().equals("handler")) {
@@ -94,20 +89,13 @@ public final class MessageHandlerChainParser {
 				}
 
 				@SuppressWarnings("unchecked")
-				Class<? extends MessageHandler<?>> handlerClass = (Class<? extends MessageHandler<?>>) Class
+				Class<? extends MessageHandler<? extends Message>> handlerClass = (Class<? extends MessageHandler<? extends Message>>) Class.forName(handlerClassName);
-						.forName(handlerClassName);
+				MessageHandler<? extends Message> handler = handlerClass.getConstructor(World.class).newInstance(world);
-				MessageHandler<?> handler = handlerClass.getConstructor(World.class).newInstance(world);
+				chainSet.putHandler(messageClass, handler);
-				handlers.add(handler);
 			}
-
-			MessageHandler<?>[] handlersArray = handlers.toArray(new MessageHandler<?>[handlers.size()]);
-			@SuppressWarnings({ "rawtypes", "unchecked" })
-			MessageHandlerChain<?> chain = new MessageHandlerChain(handlersArray);
-
-			chains.put(messageClass, chain);
 		}
 
-		return new MessageHandlerChainGroup(chains);
+		return chainSet;
 	}
 
 }

src/org/apollo/net/release/r317/FirstNpcActionMessageDecoder.java

@@ -1,7 +1,10 @@
 package org.apollo.net.release.r317;
 
 import org.apollo.game.message.impl.FirstNpcActionMessage;
-import org.apollo.net.codec.game.*;
+import org.apollo.net.codec.game.DataOrder;
+import org.apollo.net.codec.game.DataType;
+import org.apollo.net.codec.game.GamePacket;
+import org.apollo.net.codec.game.GamePacketReader;
 import org.apollo.net.release.MessageDecoder;
 
 /**

src/org/apollo/net/release/r317/SecondNpcActionMessageDecoder.java

@@ -1,7 +1,10 @@
 package org.apollo.net.release.r317;
 
 import org.apollo.game.message.impl.SecondNpcActionMessage;
-import org.apollo.net.codec.game.*;
+import org.apollo.net.codec.game.DataTransformation;
+import org.apollo.net.codec.game.DataType;
+import org.apollo.net.codec.game.GamePacket;
+import org.apollo.net.codec.game.GamePacketReader;
 import org.apollo.net.release.MessageDecoder;
 
 /**

src/org/apollo/net/release/r317/ThirdNpcActionMessageDecoder.java

@@ -1,7 +1,11 @@
 package org.apollo.net.release.r317;
 
 import org.apollo.game.message.impl.ThirdNpcActionMessage;
-import org.apollo.net.codec.game.*;
+import org.apollo.net.codec.game.DataOrder;
+import org.apollo.net.codec.game.DataTransformation;
+import org.apollo.net.codec.game.DataType;
+import org.apollo.net.codec.game.GamePacket;
+import org.apollo.net.codec.game.GamePacketReader;
 import org.apollo.net.release.MessageDecoder;
 
 /**

src/org/apollo/net/release/r377/FirstNpcActionMessageDecoder.java

@@ -1,7 +1,10 @@
 package org.apollo.net.release.r377;
 
 import org.apollo.game.message.impl.FirstNpcActionMessage;
-import org.apollo.net.codec.game.*;
+import org.apollo.net.codec.game.DataOrder;
+import org.apollo.net.codec.game.DataType;
+import org.apollo.net.codec.game.GamePacket;
+import org.apollo.net.codec.game.GamePacketReader;
 import org.apollo.net.release.MessageDecoder;
 
 /**

src/org/apollo/net/release/r377/SecondNpcActionMessageDecoder.java

@@ -1,7 +1,10 @@
 package org.apollo.net.release.r377;
 
 import org.apollo.game.message.impl.SecondNpcActionMessage;
-import org.apollo.net.codec.game.*;
+import org.apollo.net.codec.game.DataTransformation;
+import org.apollo.net.codec.game.DataType;
+import org.apollo.net.codec.game.GamePacket;
+import org.apollo.net.codec.game.GamePacketReader;
 import org.apollo.net.release.MessageDecoder;
 
 /**

src/org/apollo/net/session/GameSession.java

@@ -13,10 +13,10 @@ import org.apollo.ServerContext;
 import org.apollo.game.GameConstants;
 import org.apollo.game.GameService;
 import org.apollo.game.message.Message;
-import org.apollo.game.message.handler.MessageHandlerChain;
+import org.apollo.game.message.MessageHandlerChainSet;
-import org.apollo.game.message.handler.MessageHandlerChainGroup;
 import org.apollo.game.message.impl.LogoutMessage;
 import org.apollo.game.model.entity.Player;
+import org.apollo.util.CollectionUtil;
 
 /**
  * A game session.
@@ -81,34 +81,16 @@ public final class GameSession extends Session {
 	/**
 	 * Handles pending messages for this session.
 	 * 
-	 * @param chainGroup The message chain group.
+	 * @param chainSet The {@link MessageHandlerChainSet}
 	 */
-	@SuppressWarnings("unchecked")
+	public void handlePendingMessages(MessageHandlerChainSet chainSet) {
-	public void handlePendingMessages(MessageHandlerChainGroup chainGroup) {
+		CollectionUtil.pollAll(messageQueue, message -> {
-		Message message;
+			try {
-		while ((message = messageQueue.poll()) != null) {
+				chainSet.notify(player, message);
-			// this lookup code really sucks!
+			} catch (Exception reason) {
-			// TODO improve it!
+				logger.log(Level.SEVERE, "Uncaught exception thrown while handling message: " + message, reason);
-			Class<? extends Message> messageType = message.getClass();
-			MessageHandlerChain<Message> chain = (MessageHandlerChain<Message>) chainGroup.getChain(messageType);
-
-			while (chain == null && messageType != null) {
-				messageType = (Class<? extends Message>) messageType.getSuperclass();
-				if (messageType == Message.class) {
-					messageType = null;
-				} else {
-					chain = (MessageHandlerChain<Message>) chainGroup.getChain(messageType);
-				}
 			}
-
+		});
-			if (chain != null) {
-				try {
-					chain.handle(player, message);
-				} catch (Exception ex) {
-					logger.log(Level.SEVERE, "Error handling message: ", ex);
-				}
-			}
-		}
 	}
 
 	/**

src/org/apollo/util/CollectionUtil.java

@@ -0,0 +1,40 @@
+package org.apollo.util;
+
+import java.util.Collection;
+import java.util.Queue;
+import java.util.function.Consumer;
+
+import com.google.common.base.Preconditions;
+
+/**
+ * A utility class containing helper methods for various {@link Collection} objects.
+ * 
+ * @author Ryley
+ */
+public final class CollectionUtil {
+
+	/**
+	 * Polls every element within the specified {@link Queue} and performs the specified {@link Consumer} event for each
+	 * element.
+	 * 
+	 * @param queue The Queue to poll each element for, may not be {@code null}.
+	 * @param consumer The Consumer event to execute for each polled element, may not be {@code null}.
+	 */
+	public static <T> void pollAll(Queue<T> queue, Consumer<T> consumer) {
+		Preconditions.checkNotNull(queue, "Queue may not be null");
+		Preconditions.checkNotNull(consumer, "Consumer may not be null");
+
+		T element;
+		while ((element = queue.poll()) != null) {
+			consumer.accept(element);
+		}
+	}
+
+	/**
+	 * Suppresses the default public constructor to discourage normal instantiation outside of this class.
+	 */
+	private CollectionUtil() {
+
+	}
+
+}

src/org/apollo/util/plugin/PluginContext.java

@@ -3,9 +3,9 @@ package org.apollo.util.plugin;
 import org.apollo.ServerContext;
 import org.apollo.game.GameService;
 import org.apollo.game.message.Message;
-import org.apollo.game.message.handler.MessageHandler;
+import org.apollo.game.message.MessageHandler;
-import org.apollo.game.message.handler.MessageHandlerChain;
+import org.apollo.game.message.MessageHandlerChain;
-import org.apollo.game.message.handler.MessageHandlerChainGroup;
+import org.apollo.game.message.MessageHandlerChainSet;
 
 /**
  * The {@link PluginContext} contains methods a plugin can use to interface with the server, for example, by adding
@@ -31,20 +31,14 @@ public final class PluginContext {
 	}
 
 	/**
-	 * Adds a {@link MessageHandler} to the end of the chain.
+	 * Adds a {@link MessageHandler} to the {@link MessageHandlerChainSet}.
 	 * 
 	 * @param message The message.
 	 * @param handler The handler.
 	 */
-	public <M extends Message> void addLastMessageHandler(Class<M> message, MessageHandler<M> handler) {
+	public <M extends Message> void addMessageHandler(Class<M> message, MessageHandler<M> handler) {
-		MessageHandlerChainGroup chains = context.getService(GameService.class).getMessageHandlerChains();
+		MessageHandlerChainSet chains = context.getService(GameService.class).getMessageHandlerChainSet();
-		MessageHandlerChain<M> chain = chains.getChain(message);
+		chains.putHandler(message, handler);
-		if (chain == null) {
-			chain = new MessageHandlerChain<>(handler);
-			chains.register(message, chain);
-		} else {
-			chain.addLast(handler);
-		}
 	}
 
 }

src/org/apollo/util/xml/XmlNode.java

@@ -1,6 +1,14 @@
 package org.apollo.util.xml;
 
-import java.util.*;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+import java.util.Optional;
+import java.util.Set;
 
 /**
  * A class which represents a single node in the DOM tree, maintaining information about its children, attributes, value