Cannot Run Source Code

[MohamedElhoseny]

Exception in thread "pool-3-thread-1" java.lang.NullPointerException
at net.co.java.packets.serialization.PacketSerializer.setTotalStringLength(PacketSerializer.java:34)
at net.co.java.packets.serialization.PacketSerializer.(PacketSerializer.java:20)
at net.co.java.server.GameServerClient.handle(GameServerClient.java:58)
at net.co.java.server.AbstractClient$1.completed(AbstractClient.java:110)
at net.co.java.server.AbstractClient$1.completed(AbstractClient.java:97)
at sun.nio.ch.Invoker.invokeUnchecked(Invoker.java:126)
at sun.nio.ch.Invoker$2.run(Invoker.java:218)
at sun.nio.ch.AsynchronousChannelGroupImpl$1.run(AsynchronousChannelGroupImpl.java:112)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)