when I try to use a client event with a server, I constantly get an error:

"error, disabling clientEvent() for 127.0.0.1
java.lang.reflect.InvocationTargetException
   at sun.reflect.NativeMethodAccessorImpl.invoke0(native method)"

I have no idea why this happens

here is my code in short:

import processing.net.*;
Client myClient;
int dataIn;

void setup() {
 size(200, 200);
 // Connect to the local machine at port 5204.
 // This example will not run if you haven't
 // previously started a server on this port
 myClient = new Client(this, "127.0.0.1", 5204);
}

void draw() {
 /*
 if (myClient.available() > 0) {
   //println(myClient.read());
   dataIn = myClient.read();
 }
 background(dataIn);
 */
}

void clientEvent(Client someClient) {
 print("Server Says:  ");
 dataIn = myClient.read();
 println(dataIn);
 background(dataIn);
}