Don't create a network marker unnecessarily.

ProtocolLib/src/main/java/com/comphenix/protocol/async/AsyncMarker.java

@@ -26,6 +26,7 @@ import java.util.List;
 import java.util.concurrent.atomic.AtomicInteger;
 
 import com.comphenix.protocol.PacketStream;
+import com.comphenix.protocol.events.NetworkMarker;
 import com.comphenix.protocol.events.PacketEvent;
 import com.comphenix.protocol.injector.PrioritizedListener;
 import com.comphenix.protocol.reflect.FieldAccessException;
@@ -381,9 +382,9 @@ public class AsyncMarker implements Serializable, Comparable<AsyncMarker> {
 	void sendPacket(PacketEvent event) throws IOException {
 		try {
 			if (event.isServerPacket()) {
-				packetStream.sendServerPacket(event.getPlayer(), event.getPacket(), event.getNetworkMarker(), false);
+				packetStream.sendServerPacket(event.getPlayer(), event.getPacket(), NetworkMarker.getNetworkMarker(event), false);
 			} else {
-				packetStream.recieveClientPacket(event.getPlayer(), event.getPacket(), event.getNetworkMarker(), false);
+				packetStream.recieveClientPacket(event.getPlayer(), event.getPacket(), NetworkMarker.getNetworkMarker(event), false);
 			}
 			transmitted = true;
 			

ProtocolLib/src/main/java/com/comphenix/protocol/events/NetworkMarker.java

@@ -189,4 +189,15 @@ public class NetworkMarker {
 		}
 		return null;
 	}
+	
+	/**
+	 * Retrieve the network marker of a particular event without creating it.
+	 * <p>
+	 * This is an internal method that should not be used by API users.
+	 * @param event - the event.
+	 * @return The network marker.
+	 */
+	public static NetworkMarker getNetworkMarker(PacketEvent event) {
+		return event.networkMarker;
+	}
 }

ProtocolLib/src/main/java/com/comphenix/protocol/events/PacketEvent.java

@@ -45,7 +45,7 @@ public class PacketEvent extends EventObject implements Cancellable {
 	private boolean asynchronous;
 
 	// Network input and output handlers
-	private NetworkMarker networkMarker;
+	NetworkMarker networkMarker;
 	
 	// Whether or not a packet event is read only
 	private boolean readOnly;

ProtocolLib/src/main/java/com/comphenix/protocol/injector/PacketFilterManager.java

@@ -643,7 +643,7 @@ public final class PacketFilterManager implements ProtocolManager, ListenerInvok
 			
 			sendingListeners.invokePacketSending(
 					reporter, event, ListenerPriority.MONITOR);
-			marker = event.getNetworkMarker();
+			marker = NetworkMarker.getNetworkMarker(event);
 		}
 		playerInjection.sendServerPacket(reciever, packet, marker, filters);
 	}

ProtocolLib/src/main/java/com/comphenix/protocol/injector/player/PlayerInjector.java

@@ -611,8 +611,8 @@ public abstract class PlayerInjector implements SocketInjector {
 				
 				// Right, remember to replace the packet again
 				Object result = event.getPacket().getHandle();
-				marker = event.getNetworkMarker();
+				marker = NetworkMarker.getNetworkMarker(event);
-				
+
 				// See if we need to proxy the write method
 				if (result != null && NetworkMarker.hasOutputHandlers(marker)) {
 					result = writePacketInterceptor.constructProxy(result, event, marker);