Several improvements

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

src/main/java/com/l2jserver/service/network/NettyNetworkService.java

@@ -27,16 +27,18 @@ import org.jboss.netty.channel.socket.nio.NioServerSocketChannelFactory;
 import org.jboss.netty.logging.InternalLoggerFactory;
 import org.jboss.netty.logging.Slf4JLoggerFactory;
 
+import com.google.common.base.Preconditions;
 import com.google.inject.Inject;
 import com.google.inject.Injector;
 import com.l2jserver.game.net.Lineage2Connection;
 import com.l2jserver.game.net.Lineage2PipelineFactory;
+import com.l2jserver.game.net.packet.ServerPacket;
 import com.l2jserver.model.id.object.CharacterID;
 import com.l2jserver.service.AbstractService;
 import com.l2jserver.service.AbstractService.Depends;
 import com.l2jserver.service.configuration.ConfigurationService;
+import com.l2jserver.service.core.LoggingService;
 import com.l2jserver.service.game.world.WorldService;
-import com.l2jserver.service.logging.LoggingService;
 import com.l2jserver.service.network.keygen.BlowfishKeygenService;
 import com.l2jserver.util.factory.CollectionFactory;
 
@@ -97,6 +99,7 @@ public class NettyNetworkService extends AbstractService implements
 
 	@Override
 	public void register(final Lineage2Connection client) {
+		Preconditions.checkNotNull(client, "client");
 		clients.add(client);
 		client.getChannel().getCloseFuture()
 				.addListener(new ChannelFutureListener() {
@@ -110,11 +113,13 @@ public class NettyNetworkService extends AbstractService implements
 
 	@Override
 	public void unregister(Lineage2Connection client) {
+		Preconditions.checkNotNull(client, "client");
 		clients.remove(client);
 	}
 
 	@Override
 	public Lineage2Connection discover(CharacterID character) {
+		Preconditions.checkNotNull(character, "character");
 		for (final Lineage2Connection client : clients) {
 			if (character.equals(client.getCharacterID()))
 				return client;
@@ -122,6 +127,12 @@ public class NettyNetworkService extends AbstractService implements
 		return null;
 	}
 
+	@Override
+	public void broadcast(ServerPacket packet) {
+		Preconditions.checkNotNull(packet, "packet");
+		channel.write(packet);
+	}
+
 	@Override
 	public void cleanup() {
 		// TODO

src/main/java/com/l2jserver/service/network/NetworkService.java

@@ -17,6 +17,7 @@
 package com.l2jserver.service.network;
 
 import com.l2jserver.game.net.Lineage2Connection;
+import com.l2jserver.game.net.packet.ServerPacket;
 import com.l2jserver.model.id.object.CharacterID;
 import com.l2jserver.service.Service;
 
@@ -52,6 +53,14 @@ public interface NetworkService extends Service {
 	 */
 	Lineage2Connection discover(CharacterID character);
 
+	/**
+	 * Broadcast an given <tt>packet</tt> to all clients connected
+	 * 
+	 * @param packet
+	 *            the packet
+	 */
+	void broadcast(ServerPacket packet);
+
 	/**
 	 * Searches for idle connection and removes them
 	 */

src/main/java/com/l2jserver/service/network/keygen/BlowfishKeygenService.java

@@ -18,6 +18,20 @@ package com.l2jserver.service.network.keygen;
 
 import com.l2jserver.service.Service;
 
+/**
+ * This service generated cryptography keys used to encrypt and decrypt client
+ * or server packets. Implementations can use an fixed set of keys or generate a
+ * random one. Note that the generated key might not be cryptographically safe,
+ * and this is implementation specific.
+ * 
+ * @author <a href="http://www.rogiel.com">Rogiel</a>
+ */
 public interface BlowfishKeygenService extends Service {
+	/**
+	 * Creates a new 128 bits key. Note that the key is not necessarily random
+	 * and can be a fixed key.
+	 * 
+	 * @return the 128 bits key
+	 */
 	byte[] generate();
 }

src/main/java/com/l2jserver/service/network/keygen/PseudoRandomBlowfishKeygenService.java

@@ -22,8 +22,17 @@ import com.l2jserver.service.AbstractService;
 import com.l2jserver.service.ServiceStartException;
 import com.l2jserver.service.ServiceStopException;
 
+/**
+ * Generates a new random key using JDK {@link Random}. Keys generated by this
+ * implementation are not completely secure but are very fast to generate.
+ * 
+ * @author <a href="http://www.rogiel.com">Rogiel</a>
+ */
 public class PseudoRandomBlowfishKeygenService extends AbstractService
 		implements BlowfishKeygenService {
+	/**
+	 * The random number generator
+	 */
 	private Random random;
 
 	@Override