Several improvements

Signed-off-by: Rogiel <rogiel@rogiel.com>

src/main/java/com/l2jserver/service/game/CharacterService.java

@@ -19,8 +19,12 @@ package com.l2jserver.service.game;
 import com.l2jserver.model.world.L2Character;
 import com.l2jserver.model.world.capability.Actor;
 import com.l2jserver.service.Service;
+import com.l2jserver.service.game.SpawnService.AlreadySpawnedServiceException;
+import com.l2jserver.service.game.SpawnService.NotSpawnedServiceException;
+import com.l2jserver.service.game.SpawnService.SpawnPointNotFoundServiceException;
 import com.l2jserver.util.dimensional.Coordinate;
 import com.l2jserver.util.dimensional.Point;
+import com.l2jserver.util.exception.L2ChatServiceException;
 
 /**
  * This service manages {@link L2Character} instances
@@ -33,16 +37,24 @@ public interface CharacterService extends Service {
 	 * 
 	 * @param character
 	 *            the character
+	 * @throws SpawnPointNotFoundServiceException
+	 *             if the character does not have an spawn point defined
+	 * @throws AlreadySpawnedServiceException
+	 *             if the character is already spawned in the world
 	 */
-	void enterWorld(L2Character character);
+	void enterWorld(L2Character character)
+			throws SpawnPointNotFoundServiceException,
+			AlreadySpawnedServiceException;
 
 	/**
 	 * Perform all operations required to this character leave the world
 	 * 
 	 * @param character
 	 *            the character
+	 * @throws NotSpawnedServiceException
+	 *             if the object is not spawned in the world
 	 */
-	void leaveWorld(L2Character character);
+	void leaveWorld(L2Character character) throws NotSpawnedServiceException;
 
 	/**
 	 * Set the target of this <tt>character</tt>
@@ -51,8 +63,11 @@ public interface CharacterService extends Service {
 	 *            the character
 	 * @param actor
 	 *            the targeted actor
+	 * @throws CannotSetTargetServiceException
+	 *             if target cannot be set
 	 */
-	void target(L2Character character, Actor actor);
+	void target(L2Character character, Actor actor)
+			throws CannotSetTargetServiceException;
 
 	/**
 	 * Attacks with the given <tt>character</tt> the <tt>target</tt>
@@ -61,8 +76,36 @@ public interface CharacterService extends Service {
 	 *            the character
 	 * @param target
 	 *            the target
+	 * @throws CannotSetTargetServiceException
+	 *             if target cannot be set
 	 */
-	void attack(L2Character character, Actor target);
+	void attack(L2Character character, Actor target)
+			throws CannotSetTargetServiceException;
+
+	/**
+	 * Jails the given <tt>character</tt> for <tt>time</tt> seconds.
+	 * 
+	 * @param character
+	 *            the character
+	 * @param time
+	 *            the jail time, in seconds
+	 * @param reason
+	 *            the jail reason
+	 * @throws CharacterInJailServiceException
+	 *             if the character is already in jail
+	 */
+	void jail(L2Character character, long time, String reason)
+			throws CharacterInJailServiceException;
+
+	/**
+	 * Unjails the given <tt>character</tt>
+	 * 
+	 * @param character
+	 *            the character to be unjailed
+	 * @throws CharacterNotInJailServiceException
+	 *             if character is not in jail
+	 */
+	void unjail(L2Character character) throws CharacterNotInJailServiceException;
 
 	/**
 	 * Moves the given <tt>character</tt> to <tt>coordinate</tt>
@@ -109,4 +152,32 @@ public interface CharacterService extends Service {
 	 *            the character
 	 */
 	void run(L2Character character);
+
+	/**
+	 * Exception thrown when the target cannot be set
+	 * 
+	 * @author <a href="http://www.rogiel.com">Rogiel</a>
+	 */
+	public class CannotSetTargetServiceException extends L2ChatServiceException {
+		private static final long serialVersionUID = 1L;
+	}
+
+	/**
+	 * Exception thrown when the character is in jail
+	 * 
+	 * @author <a href="http://www.rogiel.com">Rogiel</a>
+	 */
+	public class CharacterInJailServiceException extends L2ChatServiceException {
+		private static final long serialVersionUID = 1L;
+	}
+
+	/**
+	 * Exception thrown when the character is <b>not</b> in jail
+	 * 
+	 * @author <a href="http://www.rogiel.com">Rogiel</a>
+	 */
+	public class CharacterNotInJailServiceException extends
+			L2ChatServiceException {
+		private static final long serialVersionUID = 1L;
+	}
 }

src/main/java/com/l2jserver/service/game/CharacterServiceImpl.java

@@ -16,6 +16,7 @@
  */
 package com.l2jserver.service.game;
 
+import com.google.common.base.Preconditions;
 import com.google.inject.Inject;
 import com.l2jserver.db.dao.ItemDAO;
 import com.l2jserver.game.net.Lineage2Connection;
@@ -47,6 +48,9 @@ import com.l2jserver.model.world.character.event.CharacterTargetSelectedEvent;
 import com.l2jserver.model.world.npc.event.NPCSpawnEvent;
 import com.l2jserver.service.AbstractService;
 import com.l2jserver.service.AbstractService.Depends;
+import com.l2jserver.service.game.SpawnService.AlreadySpawnedServiceException;
+import com.l2jserver.service.game.SpawnService.NotSpawnedServiceException;
+import com.l2jserver.service.game.SpawnService.SpawnPointNotFoundServiceException;
 import com.l2jserver.service.game.chat.ChatMessageDestination;
 import com.l2jserver.service.game.chat.ChatService;
 import com.l2jserver.service.game.chat.channel.ChatChannel;
@@ -114,15 +118,14 @@ public class CharacterServiceImpl extends AbstractService implements
 	}
 
 	@Override
-	public void enterWorld(final L2Character character) {
+	public void enterWorld(final L2Character character)
+			throws SpawnPointNotFoundServiceException,
+			AlreadySpawnedServiceException {
+		Preconditions.checkNotNull(character, "character");
 		final CharacterID id = character.getID();
 		final Lineage2Connection conn = networkService.discover(id);
 		if (conn == null)
 			return;
-		if (!worldService.add(character))
-			// TODO this should throw an exception
-			// character is already in the world!
-			return;
 
 		itemDao.loadInventory(character);
 
@@ -224,34 +227,23 @@ public class CharacterServiceImpl extends AbstractService implements
 		eventDispatcher.dispatch(new CharacterEnterWorldEvent(character));
 
 		// spawn the player -- this will also dispatch a spawn event
+		// here the object is registered in the world
 		spawnService.spawn(character, null);
 	}
 
 	@Override
-	public void move(L2Character character, Coordinate coordinate) {
-		final CharacterID id = character.getID();
-		final Lineage2Connection conn = networkService.discover(id);
-		// we don't set the character coordinate here, this will be done by
-		// validation packets, sent by client
-
-		// for now, let's just write the packet, we don't have much validation
-		// to be done yet. With character validation packet, another packet of
-		// these will be broadcasted.
-		conn.write(new ActorMovementPacket(character, coordinate));
-		// we don't dispatch events here, they will be dispatched by
-		// with the same packet referred up here.
-	}
-
-	@Override
-	public void leaveWorld(L2Character character) {
-		if (!worldService.remove(character))
-			return;
+	public void leaveWorld(L2Character character)
+			throws NotSpawnedServiceException {
+		Preconditions.checkNotNull(character, "character");
 		spawnService.unspawn(character);
 		eventDispatcher.dispatch(new CharacterLeaveWorldEvent(character));
 	}
 
 	@Override
-	public void target(L2Character character, Actor target) {
+	public void target(L2Character character, Actor target)
+			throws CannotSetTargetServiceException {
+		Preconditions.checkNotNull(character, "character");
+		Preconditions.checkNotNull(target, "target");
 		final CharacterID id = character.getID();
 		final Lineage2Connection conn = networkService.discover(id);
 
@@ -277,17 +269,19 @@ public class CharacterServiceImpl extends AbstractService implements
 					character, target));
 			conn.write(new CharacterTargetSelectedPacket(target));
 		} else {
-			// this indicates an inconsistency, send an action failed and reset
-			// target, i.e. deselect with no target
-			// TODO instead of sending action failed, we should throw an
-			// exception here
-			conn.sendActionFailed();
+			// this indicates an inconsistency: reset target and throws an
+			// exception
+			// this happens if tried deselect with no target
 			character.setTargetID(null);
+			throw new CannotSetTargetServiceException();
 		}
 	}
 
 	@Override
-	public void attack(L2Character character, Actor target) {
+	public void attack(L2Character character, Actor target)
+			throws CannotSetTargetServiceException {
+		Preconditions.checkNotNull(character, "character");
+		Preconditions.checkNotNull(target, "target");
 		final CharacterID id = character.getID();
 		final Lineage2Connection conn = networkService.discover(id);
 		// check if this Actor can be attacked
@@ -305,19 +299,59 @@ public class CharacterServiceImpl extends AbstractService implements
 		}
 	}
 
+	@Override
+	public void jail(L2Character character, long time, String reason)
+			throws CharacterInJailServiceException {
+		Preconditions.checkNotNull(character, "character");
+		Preconditions.checkArgument(time > 0, "time <= 0");
+		Preconditions.checkNotNull(reason, "reason");
+		// TODO implement jailing
+		throw new CharacterInJailServiceException();
+	}
+
+	@Override
+	public void unjail(L2Character character)
+			throws CharacterNotInJailServiceException {
+		Preconditions.checkNotNull(character, "character");
+		// TODO implement jailing
+		throw new CharacterNotInJailServiceException();
+	}
+
+	@Override
+	public void move(L2Character character, Coordinate coordinate) {
+		Preconditions.checkNotNull(character, "character");
+		Preconditions.checkNotNull(coordinate, "coordinate");
+		final CharacterID id = character.getID();
+		final Lineage2Connection conn = networkService.discover(id);
+		// we don't set the character coordinate here, this will be done by
+		// validation packets, sent by client
+
+		// for now, let's just write the packet, we don't have much validation
+		// to be done yet. With character validation packet, another packet of
+		// these will be broadcasted.
+		conn.write(new ActorMovementPacket(character, coordinate));
+		// we don't dispatch events here, they will be dispatched by
+		// with the same packet referred up here.
+	}
+
 	@Override
 	public void validate(L2Character character, Point point) {
+		Preconditions.checkNotNull(character, "character");
+		Preconditions.checkNotNull(point, "point");
 		// TODO implement position validation
 	}
 
 	@Override
 	public void receivedValidation(L2Character character, Point point) {
+		Preconditions.checkNotNull(character, "character");
+		Preconditions.checkNotNull(point, "point");
 		character.setPoint(point);
 		eventDispatcher.dispatch(new CharacterMoveEvent(character, point));
 	}
 
 	@Override
 	public void walk(L2Character character) {
+		Preconditions.checkNotNull(character, "character");
 		final CharacterID id = character.getID();
 		final Lineage2Connection conn = networkService.discover(id);
 		// test if character is running
@@ -332,6 +366,7 @@ public class CharacterServiceImpl extends AbstractService implements
 
 	@Override
 	public void run(L2Character character) {
+		Preconditions.checkNotNull(character, "character");
 		final CharacterID id = character.getID();
 		final Lineage2Connection conn = networkService.discover(id);
 		// test if character is walking

src/main/java/com/l2jserver/service/game/GameTimeService.java

@@ -24,6 +24,11 @@ import com.l2jserver.service.Service;
  * @author <a href="http://www.rogiel.com">Rogiel</a>
  */
 public interface GameTimeService extends Service {
+	/**
+	 * The real time length of a day in-game in milliseconds.
+	 */
+	public static final int GAME_DAY = 120 * 60 * 1000;
+
 	/**
 	 * Returns the in-game time
 	 * 

src/main/java/com/l2jserver/service/game/GameTimeServiceImpl.java

@@ -27,7 +27,6 @@ public class GameTimeServiceImpl extends AbstractService implements
 		GameTimeService {
 	@Override
 	public int getGameTime() {
-		// TODO implement this!
-		return (int) (System.currentTimeMillis() / 1000);
+		return (int) (System.currentTimeMillis() % GAME_DAY) / 1000;
 	}
 }

src/main/java/com/l2jserver/service/game/MonsterService.java

@@ -0,0 +1,38 @@
+/*
+ * This file is part of l2jserver <l2jserver.com>.
+ *
+ * l2jserver is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * l2jserver is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with l2jserver.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package com.l2jserver.service.game;
+
+import com.l2jserver.model.world.L2Character;
+import com.l2jserver.model.world.NPC;
+import com.l2jserver.service.Service;
+
+/**
+ * This service controls {@link NPC}s
+ * 
+ * @author <a href="http://www.rogiel.com">Rogiel</a>
+ */
+public interface MonsterService extends Service {
+	/**
+	 * Interacts the given <tt>player</tt> with the given <tt>npc</tt>
+	 * 
+	 * @param npc
+	 *            the npc
+	 * @param character
+	 *            the character
+	 */
+	void interact(NPC npc, L2Character character);
+}

src/main/java/com/l2jserver/service/game/SpawnService.java

@@ -23,6 +23,7 @@ import com.l2jserver.model.world.player.event.PlayerTeleportEvent;
 import com.l2jserver.service.Service;
 import com.l2jserver.util.dimensional.Coordinate;
 import com.l2jserver.util.dimensional.Point;
+import com.l2jserver.util.exception.L2SpawnServiceException;
 
 /**
  * This service is responsible for spawning monsters, npcs and players.
@@ -41,8 +42,15 @@ public interface SpawnService extends Service {
 	 * @param point
 	 *            the spawning point. If null, will try to use
 	 *            {@link Spawnable#getPoint()}.
+	 * @throws SpawnPointNotFoundServiceException
+	 *             if could not find an spawn point (i.e <tt>point</tt> and
+	 *             {@link Spawnable#getPoint()} are null)
+	 * @throws AlreadySpawnedServiceException
+	 *             if the object is already spawned in the world
 	 */
-	void spawn(Spawnable spawnable, Point point);
+	void spawn(Spawnable spawnable, Point point)
+			throws SpawnPointNotFoundServiceException,
+			AlreadySpawnedServiceException;
 
 	/**
 	 * Teleports the object to the given <tt>point</tt>.
@@ -54,11 +62,16 @@ public interface SpawnService extends Service {
 	 *            the player object
 	 * @param coordinate
 	 *            the teleportation coordinate
+	 * @throws NotSpawnedServiceException
+	 *             if the object to be teleported is not spawned
 	 */
-	void teleport(Player player, Coordinate coordinate);
+	void teleport(Player player, Coordinate coordinate)
+			throws NotSpawnedServiceException;
 
 	/**
 	 * Schedules an {@link Spawnable} object to be respawn in a certain time.
+	 * <p>
+	 * TODO this is not complete
 	 * 
 	 * @param spawnable
 	 *            the spawnable object
@@ -70,6 +83,37 @@ public interface SpawnService extends Service {
 	 * 
 	 * @param spawnable
 	 *            the spawnable object
+	 * @throws NotSpawnedServiceException
+	 *             if the object is not spawned
 	 */
-	void unspawn(Spawnable spawnable);
+	void unspawn(Spawnable spawnable) throws NotSpawnedServiceException;
+
+	/**
+	 * Exception thrown when the object is already spawned and registered in the
+	 * world
+	 * 
+	 * @author <a href="http://www.rogiel.com">Rogiel</a>
+	 */
+	public class AlreadySpawnedServiceException extends L2SpawnServiceException {
+		private static final long serialVersionUID = 1L;
+	}
+
+	/**
+	 * Exception thrown when the target spawn point is not found
+	 * 
+	 * @author <a href="http://www.rogiel.com">Rogiel</a>
+	 */
+	public class SpawnPointNotFoundServiceException extends
+			L2SpawnServiceException {
+		private static final long serialVersionUID = 1L;
+	}
+
+	/**
+	 * Exception thrown when trying to unspawn an object that is not spawned
+	 * 
+	 * @author <a href="http://www.rogiel.com">Rogiel</a>
+	 */
+	public class NotSpawnedServiceException extends L2SpawnServiceException {
+		private static final long serialVersionUID = 1L;
+	}
 }

src/main/java/com/l2jserver/service/game/SpawnServiceImpl.java

@@ -19,6 +19,7 @@ package com.l2jserver.service.game;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import com.google.common.base.Preconditions;
 import com.google.inject.Inject;
 import com.l2jserver.game.net.Lineage2Connection;
 import com.l2jserver.game.net.packet.server.CharacterTeleportPacket;
@@ -72,16 +73,16 @@ public class SpawnServiceImpl extends AbstractService implements SpawnService {
 	}
 
 	@Override
-	public void spawn(Spawnable spawnable, Point point) {
+	public void spawn(Spawnable spawnable, Point point)
+			throws SpawnPointNotFoundServiceException {
+		Preconditions.checkNotNull(spawnable, "spawnable");
 		// sanitize
 		if (point == null)
 			// retrieving stored point
 			point = spawnable.getPoint();
 		if (point == null) {
 			// not point send and no point stored, aborting
-			// TODO this should throw an exception
-			log.warn("Trying to spawn {} to a null point", spawnable);
-			return;
+			throw new SpawnPointNotFoundServiceException();
 		}
 
 		// set the spawning point
@@ -110,6 +111,8 @@ public class SpawnServiceImpl extends AbstractService implements SpawnService {
 
 	@Override
 	public void teleport(Player player, Coordinate coordinate) {
+		Preconditions.checkNotNull(player, "player");
+		Preconditions.checkNotNull(coordinate, "coordinate");
 		player.setPosition(coordinate);
 		if (player instanceof L2Character) {
 			final Lineage2Connection conn = networkService
@@ -127,12 +130,14 @@ public class SpawnServiceImpl extends AbstractService implements SpawnService {
 
 	@Override
 	public void scheduleRespawn(Spawnable spawnable) {
+		Preconditions.checkNotNull(spawnable, "spawnable");
 		// TODO Auto-generated method stub
 
 	}
 
 	@Override
 	public void unspawn(Spawnable spawnable) {
+		Preconditions.checkNotNull(spawnable, "spawnable");
 		// TODO Auto-generated method stub
 
 	}

src/main/java/com/l2jserver/service/game/ai/AIServiceImpl.java

@@ -22,11 +22,11 @@ import com.l2jserver.service.AbstractService;
 import com.l2jserver.service.AbstractService.Depends;
 import com.l2jserver.service.ServiceStartException;
 import com.l2jserver.service.ServiceStopException;
+import com.l2jserver.service.core.threading.ThreadService;
 import com.l2jserver.service.game.template.TemplateService;
 import com.l2jserver.service.game.world.WorldService;
 import com.l2jserver.service.game.world.event.WorldEventDispatcher;
 import com.l2jserver.service.network.NetworkService;
-import com.l2jserver.service.threading.ThreadService;
 import com.l2jserver.util.dimensional.Coordinate;
 
 /**

src/main/java/com/l2jserver/service/game/chat/ChatMessageDestination.java

@@ -16,6 +16,11 @@
  */
 package com.l2jserver.service.game.chat;
 
+/**
+ * Enumeration of all possible message destinations
+ * 
+ * @author <a href="http://www.rogiel.com">Rogiel</a>
+ */
 public enum ChatMessageDestination {
 	/**
 	 * Everyone
@@ -44,9 +49,17 @@ public enum ChatMessageDestination {
 	/**
 	 * $
 	 */
-	ALLIANCE(9), ANNOUNCEMENT(10), BOAT(11), L2FRIEND(12), MSNCHAT(13), PARTYMATCH_ROOM(
-			14), PARTYROOM_COMMANDER(15), PARTYROOM_ALL(16), HERO_VOICE(17), CRITICAL_ANNOUNCE(
-			18), SCREEN_ANNOUNCE(19), BATTLEFIELD(20), MPCC_ROOM(21);
+	ALLIANCE(9),
+	/**
+	 * Announcement
+	 */
+	ANNOUNCEMENT(10),
+	/**
+	 * Boat
+	 */
+	BOAT(11), L2FRIEND(12), MSNCHAT(13), PARTYMATCH_ROOM(14), PARTYROOM_COMMANDER(
+			15), PARTYROOM_ALL(16), HERO_VOICE(17), CRITICAL_ANNOUNCE(18), SCREEN_ANNOUNCE(
+			19), BATTLEFIELD(20), MPCC_ROOM(21);
 
 	public final int id;
 

src/main/java/com/l2jserver/service/game/chat/ChatService.java

@@ -110,16 +110,32 @@ public interface ChatService extends Service {
 
 	// TODO party chat
 
+	/**
+	 * Exception thrown when the target of an private chat is not found
+	 * 
+	 * @author <a href="http://www.rogiel.com">Rogiel</a>
+	 */
 	public class TargetNotFoundChatServiceException extends
 			L2ChatServiceException {
 		private static final long serialVersionUID = 1L;
 	}
 
+	/**
+	 * Exception thrown if the player is trying to chat with itself.
+	 * 
+	 * @author <a href="http://www.rogiel.com">Rogiel</a>
+	 */
 	public class CannotChatToSelfChatServiceException extends
 			L2ChatServiceException {
 		private static final long serialVersionUID = 1L;
 	}
 
+	/**
+	 * Exception thrown if the player trying to send a message is currently
+	 * banned.
+	 * 
+	 * @author <a href="http://www.rogiel.com">Rogiel</a>
+	 */
 	public class ChatBanActiveChatServiceException extends
 			L2ChatServiceException {
 		private static final long serialVersionUID = 1L;

src/main/java/com/l2jserver/service/game/chat/SimpleChatService.java

@@ -19,6 +19,7 @@ package com.l2jserver.service.game.chat;
 import java.util.Map;
 import java.util.Set;
 
+import com.google.common.base.Preconditions;
 import com.google.inject.Inject;
 import com.l2jserver.db.dao.CharacterDAO;
 import com.l2jserver.model.id.object.CharacterID;
@@ -106,7 +107,12 @@ public class SimpleChatService extends AbstractService implements ChatService {
 	public void send(CharacterID sender, ChatMessageDestination chat,
 			String message, String extra)
 			throws TargetNotFoundChatServiceException,
-			CannotChatToSelfChatServiceException {
+			CannotChatToSelfChatServiceException,
+			ChatBanActiveChatServiceException {
+		Preconditions.checkNotNull(sender, "sender");
+		Preconditions.checkNotNull(message, "message");
+		Preconditions.checkNotNull(extra, "extra");
+
 		final ChatChannel channel;
 		switch (chat) {
 		case ALL:
@@ -122,7 +128,7 @@ public class SimpleChatService extends AbstractService implements ChatService {
 			final L2Character character = charDao.selectByName(extra);
 			if (character == null)
 				throw new TargetNotFoundChatServiceException();
-			if (character.equals(sender))
+			if (character.getID().equals(sender))
 				throw new CannotChatToSelfChatServiceException();
 			channel = getChannel(character.getID());
 			break;
@@ -152,6 +158,7 @@ public class SimpleChatService extends AbstractService implements ChatService {
 
 	@Override
 	public PublicChatChannel getRegionChannel(L2Character character) {
+		Preconditions.checkNotNull(character, "character");
 		final Region region = regionService.getRegion(character);
 		RegionChatChannelImpl channel = regionChannels.get(region);
 		if (channel == null) {
@@ -163,6 +170,7 @@ public class SimpleChatService extends AbstractService implements ChatService {
 
 	@Override
 	public PrivateChatChannel getChannel(CharacterID character) {
+		Preconditions.checkNotNull(character, "character");
 		if (character == null)
 			return null;
 		PrivateChatChannelImpl channel = privateChannels.get(character);
@@ -175,6 +183,7 @@ public class SimpleChatService extends AbstractService implements ChatService {
 
 	@Override
 	public PublicChatChannel getChannel(ClanID clan) {
+		Preconditions.checkNotNull(clan, "clan");
 		if (clan == null)
 			return null;
 		ClanChatChannelImpl channel = clanChannels.get(clan);
@@ -207,6 +216,9 @@ public class SimpleChatService extends AbstractService implements ChatService {
 
 		@Override
 		public void send(CharacterID sender, String message) {
+			Preconditions.checkNotNull(sender, "sender");
+			Preconditions.checkNotNull(message, "message");
+			// TODO throw exception if sender is banned from chat
 			for (final ChatChannelListener listener : listeners) {
 				listener.onMessage(this, sender, message);
 			}
@@ -214,11 +226,13 @@ public class SimpleChatService extends AbstractService implements ChatService {
 
 		@Override
 		public void addChatChannelListener(ChatChannelListener listener) {
+			Preconditions.checkNotNull(listener, "listener");
 			listeners.add(listener);
 		}
 
 		@Override
 		public void removeChatChannelListener(ChatChannelListener listener) {
+			Preconditions.checkNotNull(listener, "listener");
 			listeners.remove(listener);
 		}
 	}
@@ -233,6 +247,7 @@ public class SimpleChatService extends AbstractService implements ChatService {
 		private final CharacterID character;
 
 		public PrivateChatChannelImpl(CharacterID character) {
+			Preconditions.checkNotNull(character, "character");
 			this.character = character;
 		}
 
@@ -288,6 +303,7 @@ public class SimpleChatService extends AbstractService implements ChatService {
 		 * @param clanID
 		 */
 		public ClanChatChannelImpl(ClanID clanID) {
+			Preconditions.checkNotNull(clanID, "clanID");
 			this.clanID = clanID;
 		}
 	}
@@ -311,6 +327,7 @@ public class SimpleChatService extends AbstractService implements ChatService {
 		 * @param clanID
 		 */
 		public RegionChatChannelImpl(Region region) {
+			Preconditions.checkNotNull(region, "region");
 			this.region = region;
 		}
 	}

src/main/java/com/l2jserver/service/game/chat/channel/ChatChannel.java

@@ -17,6 +17,7 @@
 package com.l2jserver.service.game.chat.channel;
 
 import com.l2jserver.model.id.object.CharacterID;
+import com.l2jserver.service.game.chat.ChatService.ChatBanActiveChatServiceException;
 
 /**
  * The {@link ChatChannel} object is used to send messages to a channel.
@@ -35,8 +36,11 @@ public interface ChatChannel {
 	 *            the character sending the message
 	 * @param message
 	 *            the message to be sent
+	 * @throws ChatBanActiveChatServiceException
+	 *             if <tt>sender</tt> is banned from chatting
 	 */
-	void send(CharacterID sender, String message);
+	void send(CharacterID sender, String message)
+			throws ChatBanActiveChatServiceException;
 
 	/**
 	 * Adds a {@link ChatChannelListener} that will be notified once a message

src/main/java/com/l2jserver/service/game/scripting/ScriptingServiceImpl.java

@@ -28,16 +28,17 @@ import javax.xml.bind.Unmarshaller;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import com.google.common.base.Preconditions;
 import com.google.inject.Inject;
 import com.google.inject.Injector;
 import com.l2jserver.service.AbstractService;
 import com.l2jserver.service.AbstractService.Depends;
 import com.l2jserver.service.ServiceStartException;
 import com.l2jserver.service.ServiceStopException;
+import com.l2jserver.service.core.LoggingService;
 import com.l2jserver.service.game.scripting.impl.ScriptContextImpl;
 import com.l2jserver.service.game.scripting.scriptmanager.ScriptInfo;
 import com.l2jserver.service.game.scripting.scriptmanager.ScriptList;
-import com.l2jserver.service.logging.LoggingService;
 import com.l2jserver.util.factory.CollectionFactory;
 
 /**
@@ -84,6 +85,7 @@ public class ScriptingServiceImpl extends AbstractService implements
 	@Override
 	public synchronized List<ScriptContext> load(File scriptDescriptor)
 			throws Exception {
+		Preconditions.checkNotNull(scriptDescriptor, "scriptDescriptor");
 		final JAXBContext c = JAXBContext.newInstance(ScriptInfo.class,
 				ScriptList.class);
 		final Unmarshaller u = c.createUnmarshaller();
@@ -115,6 +117,9 @@ public class ScriptingServiceImpl extends AbstractService implements
 	 */
 	private ScriptContext createContext(ScriptInfo si, ScriptContext parent)
 			throws Exception {
+		Preconditions.checkNotNull(si, "si");
+		Preconditions.checkNotNull(parent, "parent");
+		
 		ScriptContext context = getScriptContext(si.getRoot(), parent);
 		context.setLibraries(si.getLibraries());
 		context.setCompilerClassName(si.getCompilerClass());
@@ -153,6 +158,9 @@ public class ScriptingServiceImpl extends AbstractService implements
 	 */
 	private ScriptContext getScriptContext(File root, ScriptContext parent)
 			throws InstantiationException {
+		Preconditions.checkNotNull(root, "root");
+		Preconditions.checkNotNull(parent, "parent");
+		
 		ScriptContextImpl ctx;
 		if (parent == null) {
 			ctx = new ScriptContextImpl(injector, root);

src/main/java/com/l2jserver/service/game/template/ScriptTemplateService.java

@@ -18,6 +18,7 @@ package com.l2jserver.service.game.template;
 
 import java.util.Map;
 
+import com.google.common.base.Preconditions;
 import com.google.inject.Inject;
 import com.google.inject.Injector;
 import com.l2jserver.model.id.TemplateID;
@@ -27,9 +28,9 @@ import com.l2jserver.service.AbstractService.Depends;
 import com.l2jserver.service.ServiceStartException;
 import com.l2jserver.service.ServiceStopException;
 import com.l2jserver.service.configuration.ConfigurationService;
+import com.l2jserver.service.core.LoggingService;
 import com.l2jserver.service.game.scripting.ScriptContext;
 import com.l2jserver.service.game.scripting.ScriptingService;
-import com.l2jserver.service.logging.LoggingService;
 import com.l2jserver.util.factory.CollectionFactory;
 
 @Depends({ LoggingService.class, ConfigurationService.class,
@@ -73,10 +74,13 @@ public class ScriptTemplateService extends AbstractService implements
 	@Override
 	@SuppressWarnings("unchecked")
 	public <T extends Template<?>> T getTemplate(TemplateID<T> id) {
+		Preconditions.checkNotNull(id, "id");
 		return (T) templates.get(id);
 	}
 
 	public void addTemplate(Class<? extends Template<?>> t) {
+		Preconditions.checkNotNull(t, "t");
+
 		final Template<?> template = injector.getInstance(t);
 		if (templates.containsKey(template.getID()))
 			throw new TemplateException("Template with ID" + template.getID()
@@ -88,6 +92,7 @@ public class ScriptTemplateService extends AbstractService implements
 	}
 
 	public void removeTemplate(Template<?> t) {
+		Preconditions.checkNotNull(t, "t");
 		// TODO templates.remove(t);
 	}
 

src/main/java/com/l2jserver/service/game/world/CachedWorldIDService.java

@@ -23,6 +23,7 @@ import net.sf.ehcache.Element;
 import net.sf.ehcache.config.CacheConfiguration;
 import net.sf.ehcache.store.MemoryStoreEvictionPolicy;
 
+import com.google.common.base.Preconditions;
 import com.google.inject.Inject;
 import com.l2jserver.db.dao.CharacterDAO;
 import com.l2jserver.db.dao.ItemDAO;
@@ -114,6 +115,7 @@ public class CachedWorldIDService extends AbstractService implements
 	 *            an collection of ids
 	 */
 	private void load(Collection<? extends ObjectID<?>> ids) {
+		Preconditions.checkNotNull(ids, "ids");
 		for (final ObjectID<?> id : ids) {
 			allocator.allocate(id.getID());
 			add(id);
@@ -123,6 +125,7 @@ public class CachedWorldIDService extends AbstractService implements
 	@Override
 	@SuppressWarnings("unchecked")
 	public <I extends ObjectID<?>> I resolve(int id) {
+		Preconditions.checkNotNull(id, "id");
 		if (!loaded) {
 			// ignore resolving before all IDs are loaded
 			return null;
@@ -136,6 +139,7 @@ public class CachedWorldIDService extends AbstractService implements
 
 	@Override
 	public <I extends ObjectID<?>> void add(I id) {
+		Preconditions.checkNotNull(id, "id");
 		if (id == null)
 			return;
 		cache.put(new Element(id.getID(), id));
@@ -143,6 +147,7 @@ public class CachedWorldIDService extends AbstractService implements
 
 	@Override
 	public <I extends ObjectID<?>> void remove(I id) {
+		Preconditions.checkNotNull(id, "id");
 		cache.remove(id.getID());
 	}
 

src/main/java/com/l2jserver/service/game/world/WorldServiceImpl.java

@@ -23,6 +23,7 @@ import java.util.Set;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import com.google.common.base.Preconditions;
 import com.google.inject.Inject;
 import com.l2jserver.model.id.ObjectID;
 import com.l2jserver.model.world.WorldObject;
@@ -31,6 +32,7 @@ import com.l2jserver.service.AbstractService;
 import com.l2jserver.service.AbstractService.Depends;
 import com.l2jserver.service.ServiceStartException;
 import com.l2jserver.service.ServiceStopException;
+import com.l2jserver.service.core.LoggingService;
 import com.l2jserver.service.database.DatabaseService;
 import com.l2jserver.service.game.scripting.ScriptingService;
 import com.l2jserver.service.game.template.TemplateService;
@@ -41,7 +43,6 @@ import com.l2jserver.service.game.world.filter.WorldObjectFilter;
 import com.l2jserver.service.game.world.filter.impl.IDFilter;
 import com.l2jserver.service.game.world.filter.impl.InstanceFilter;
 import com.l2jserver.service.game.world.filter.impl.KnownListFilter;
-import com.l2jserver.service.logging.LoggingService;
 import com.l2jserver.util.factory.CollectionFactory;
 
 /**
@@ -87,12 +88,14 @@ public class WorldServiceImpl extends AbstractService implements WorldService {
 
 	@Override
 	public boolean add(WorldObject object) {
+		Preconditions.checkNotNull(object, "object");
 		log.debug("Adding object {} to world", object);
 		return objects.add(object);
 	}
 
 	@Override
 	public boolean remove(WorldObject object) {
+		Preconditions.checkNotNull(object, "object");
 		log.debug("Removing object {} from world", object);
 		// we also need to remove all listeners for this object
 		dispatcher.clear(object.getID());
@@ -101,12 +104,14 @@ public class WorldServiceImpl extends AbstractService implements WorldService {
 
 	@Override
 	public boolean contains(WorldObject object) {
+		Preconditions.checkNotNull(object, "object");
 		return objects.contains(object);
 	}
 
 	@Override
 	@SuppressWarnings("unchecked")
 	public <T extends WorldObject> T find(ObjectID<T> id) {
+		Preconditions.checkNotNull(id, "id");
 		final IDFilter filter = new IDFilter(id);
 		for (final WorldObject object : objects) {
 			if (filter.accept(object))
@@ -118,10 +123,8 @@ public class WorldServiceImpl extends AbstractService implements WorldService {
 
 	@Override
 	public void knownlist(Positionable object, KnownListCallback callback) {
-		if (object == null)
-			return;
-		if (callback == null)
-			return;
+		Preconditions.checkNotNull(object, "object");
+		Preconditions.checkNotNull(callback, "callback");
 		for (Positionable known : iterable(new KnownListFilter(object))) {
 			callback.knownObject(known);
 		}
@@ -134,6 +137,7 @@ public class WorldServiceImpl extends AbstractService implements WorldService {
 
 	@Override
 	public <T extends WorldObject> List<T> list(WorldObjectFilter<T> filter) {
+		Preconditions.checkNotNull(filter, "filter");
 		log.debug("Listing objects with filter {}", filter);
 		final List<T> list = CollectionFactory.newList();
 		for (final T object : this.iterable(filter)) {
@@ -144,6 +148,7 @@ public class WorldServiceImpl extends AbstractService implements WorldService {
 
 	@Override
 	public <T extends WorldObject> List<T> list(Class<T> type) {
+		Preconditions.checkNotNull(type, "type");
 		log.debug("Listing of type {}", type);
 		return list(new InstanceFilter<T>(type));
 	}
@@ -156,12 +161,14 @@ public class WorldServiceImpl extends AbstractService implements WorldService {
 	@Override
 	public <T extends WorldObject> Iterator<T> iterator(
 			final WorldObjectFilter<T> filter) {
+		Preconditions.checkNotNull(filter, "filter");
 		return new FilterIterator<T>(filter, objects.iterator());
 	}
 
 	@Override
 	public <T extends WorldObject> Iterable<T> iterable(
 			final WorldObjectFilter<T> filter) {
+		Preconditions.checkNotNull(filter, "filter");
 		return new Iterable<T>() {
 			@Override
 			public Iterator<T> iterator() {

src/main/java/com/l2jserver/service/game/world/event/FilteredWorldListener.java

@@ -16,6 +16,7 @@
  */
 package com.l2jserver.service.game.world.event;
 
+import com.google.common.base.Preconditions;
 import com.l2jserver.model.world.WorldObject;
 import com.l2jserver.service.game.world.filter.WorldObjectFilter;
 
@@ -30,6 +31,7 @@ public abstract class FilteredWorldListener<T extends WorldObject> implements
 	private final WorldObjectFilter<T> filter;
 
 	public FilteredWorldListener(WorldObjectFilter<T> filter) {
+		Preconditions.checkNotNull(filter, "filter");
 		this.filter = filter;
 	}
 

src/main/java/com/l2jserver/service/game/world/event/TypedWorldListener.java

@@ -16,6 +16,8 @@
  */
 package com.l2jserver.service.game.world.event;
 
+import com.google.common.base.Preconditions;
+
 /**
  * This listener will filter to only dispatch an certain type events.
  * 
@@ -25,6 +27,7 @@ public abstract class TypedWorldListener<T> implements WorldListener {
 	private final Class<T> type;
 
 	public TypedWorldListener(Class<T> type) {
+		Preconditions.checkNotNull(type, "type");
 		this.type = type;
 	}
 

src/main/java/com/l2jserver/service/game/world/event/WorldEventDispatcherImpl.java

@@ -28,6 +28,7 @@ import java.util.concurrent.TimeoutException;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import com.google.common.base.Preconditions;
 import com.google.common.util.concurrent.AbstractFuture;
 import com.l2jserver.model.id.ObjectID;
 import com.l2jserver.model.world.WorldObject;
@@ -92,6 +93,7 @@ public class WorldEventDispatcherImpl implements WorldEventDispatcher {
 
 	@Override
 	public <E extends WorldEvent> WorldEventFuture<E> dispatch(E event) {
+		Preconditions.checkNotNull(event, "event");
 		log.debug("Queing dispatch for event {}", event);
 		final WorldEventFutureImpl<E> future = new WorldEventFutureImpl<E>();
 		events.add(new EventContainer(event, future));
@@ -119,10 +121,9 @@ public class WorldEventDispatcherImpl implements WorldEventDispatcher {
 					if (!listener.dispatch(event.event))
 						// remove listener if return value is false
 						listeners.remove(listener);
-				} catch (ClassCastException e) {
-					log.debug(
-							"Exception in Listener. This might indicate an implementation issue in {}",
-							listener.getClass());
+				} catch (Throwable t) {
+					log.warn("Exception in listener", t);
+					// always remove any listener that throws an exception
 					listeners.remove(listener);
 				}
 			}
@@ -132,33 +133,43 @@ public class WorldEventDispatcherImpl implements WorldEventDispatcher {
 
 	@Override
 	public void addListener(WorldListener listener) {
+		Preconditions.checkNotNull(listener, "listener");
 		log.debug("Adding new listener global {}", listener);
 		globalListeners.add(listener);
 	}
 
 	@Override
 	public void addListener(WorldObject object, WorldListener listener) {
+		Preconditions.checkNotNull(object, "object");
+		Preconditions.checkNotNull(listener, "listener");
 		addListener(object.getID(), listener);
 	}
 
 	@Override
 	public void addListener(ObjectID<?> id, WorldListener listener) {
+		Preconditions.checkNotNull(id, "id");
+		Preconditions.checkNotNull(listener, "listener");
 		log.debug("Adding new listener {} to {}", listener, id);
 		getListeners(id).add(listener);
 	}
 
 	@Override
 	public void removeListener(WorldListener listener) {
+		Preconditions.checkNotNull(listener, "listener");
 		globalListeners.remove(listener);
 	}
 
 	@Override
 	public void removeListener(WorldObject object, WorldListener listener) {
+		Preconditions.checkNotNull(object, "object");
+		Preconditions.checkNotNull(listener, "listener");
 		removeListener(object.getID(), listener);
 	}
 
 	@Override
 	public void removeListener(ObjectID<?> id, WorldListener listener) {
+		Preconditions.checkNotNull(id, "id");
+		Preconditions.checkNotNull(listener, "listener");
 		log.debug("Removing new listener {} from {}", listener, id);
 		getListeners(id).remove(listener);
 	}
@@ -170,6 +181,7 @@ public class WorldEventDispatcherImpl implements WorldEventDispatcher {
 	 *            the object id
 	 */
 	public void clear(ObjectID<?> id) {
+		Preconditions.checkNotNull(id, "id");
 		listeners.remove(id);
 	}
 
@@ -182,6 +194,7 @@ public class WorldEventDispatcherImpl implements WorldEventDispatcher {
 	 * @return the {@link Set}. Never null.
 	 */
 	private Set<WorldListener> getListeners(ObjectID<?> id) {
+		Preconditions.checkNotNull(id, "id");
 		Set<WorldListener> set = listeners.get(id);
 		if (set == null) {
 			set = CollectionFactory.newSet();
@@ -189,7 +202,7 @@ public class WorldEventDispatcherImpl implements WorldEventDispatcher {
 		}
 		return set;
 	}
-	
+
 	public void stop() {
 		timer.cancel();
 		timer = null;

src/main/java/com/l2jserver/service/game/world/filter/impl/IDFilter.java

@@ -16,6 +16,7 @@
  */
 package com.l2jserver.service.game.world.filter.impl;
 
+import com.google.common.base.Preconditions;
 import com.l2jserver.model.id.ObjectID;
 import com.l2jserver.model.world.WorldObject;
 import com.l2jserver.service.game.world.filter.WorldObjectFilter;
@@ -38,6 +39,7 @@ public class IDFilter implements WorldObjectFilter<WorldObject> {
 	 *            the desired object ID
 	 */
 	public IDFilter(final ObjectID<?> id) {
+		Preconditions.checkNotNull(id, "id");
 		this.id = id;
 	}
 

src/main/java/com/l2jserver/service/game/world/filter/impl/InstanceFilter.java

@@ -16,6 +16,7 @@
  */
 package com.l2jserver.service.game.world.filter.impl;
 
+import com.google.common.base.Preconditions;
 import com.l2jserver.model.world.WorldObject;
 import com.l2jserver.service.game.world.filter.WorldObjectFilter;
 
@@ -40,6 +41,7 @@ public class InstanceFilter<T extends WorldObject> implements
 	 *            the instance type
 	 */
 	public InstanceFilter(Class<?> instance) {
+		Preconditions.checkNotNull(instance, "instance");
 		this.type = instance;
 	}
 

src/main/java/com/l2jserver/service/game/world/filter/impl/RangeFilter.java

@@ -16,6 +16,7 @@
  */
 package com.l2jserver.service.game.world.filter.impl;
 
+import com.google.common.base.Preconditions;
 import com.l2jserver.model.world.capability.Positionable;
 import com.l2jserver.service.game.world.filter.WorldObjectFilter;
 
@@ -43,6 +44,8 @@ public class RangeFilter implements WorldObjectFilter<Positionable> {
 	 *            the desired maximum distance of the object
 	 */
 	public RangeFilter(final Positionable object, final int range) {
+		Preconditions.checkNotNull(object, "object");
+		Preconditions.checkState(range >= 0, "range < 0");
 		this.object = object;
 		this.range = range;
 	}