NullPointerException on the RMI server side.

My situation is as below:

on the RMI client side, there is a callback class exported in its constructor and then as a argument invoke the remote method of the server side. The remote class is retrivied from the registry.

CallBack cb = new CallBack();

MyRemoteObj ojb = Registry.lookup("MyRemoteObj");

obj. action('' test", cb);

on the RMI server side:

1. create a registry using LocateRegistry.createRegistry(port , MyRMISSLClientSocketFactory,MyRMISSLServerSocketFactory)

2.bind my remote object in the registry.

When I run my client, and find clent successfully done. But the server raised above problem.

That exeception from a separate thread that I can't catch it.

Do anyone know why? Thanks in advance.

chendcha at 2007-7-14 22:00:52 >

Thanks ejp,

The Constructor of the class CallBack is:

abstract Class CallBack {

CallBack(

UnicastRemoteObject.exportObject(this, port, new MyRMISSLClientSocketFactory(),

new MyRMISSLServerSocketFactory());

)

public Object invoke(String str,Object data) throws RemoteException;

}

all the callback sub class will extend this class and implements the special invoke method.

client didn't create any registry, just

Registry registry=LocateRegistry.getRegistry(iHost, iPort,

nw MyRMISSLSocketFactory());

and use this registry to get remote object by name( A string like "MyRemoteObj" which bind in server side);

Do you anything want to know?

chendcha at 2007-7-14 22:00:52 >