Java Corba Help

Question

Hi,
I'm using Java 1.5 to try out some Corba stuff with the idlj compiler, and am getting errors while testing. Can anyone show me what the problem is? The error is when i run the client code and the error is denoted where i put the comment //CRASH HERE. The stack trace is below as well:
My IDL:
module corbatest
interface Device_CI
readonly attribute long deviceID;
interface NorthBoundInterface
corbatest::Device_CI GetDevice(in long deviceID);
//SERVER CODE
import corbatest.*;
public class DeviceImpl extends Device_CIPOA{
public DeviceImpl() { }
public int deviceID() {
return 44;
import corbatest.*;
import org.omg.CORBA.*;
public class NorthBoundInterfaceImpl extends NorthBoundInterfacePOA {
private ORB orb;
public void setORB(ORB val) {
val = orb;
public Device_CI GetDevice (int deviceID) {
DeviceImpl dev = new DeviceImpl();
Device_CIPOATie tie = new Device_CIPOATie(dev);
return tie._this(orb);
import corbatest.*;
import org.omg.CosNaming.*;
import org.omg.CosNaming.NamingContextPackage.*;
import org.omg.CORBA.*;
import org.omg.PortableServer.*;
import org.omg.PortableServer.POA;
import java.util.Properties;
public class Server{
public static void main(String args[]){
try{
// create and initialize the ORB
     Properties properties = new Properties();
     properties.put("org.omg.CORBA.ORBInitialPort", "1050");
     properties.put("org.omg.CORBA.ORBInitialHost", "localhost");
     ORB orb = ORB.init((String[])null, properties);
// Get reference to rootpoa & activate the POAManager
POA rootpoa = POAHelper.narrow(orb.resolve_initial_references("RootPOA"));
rootpoa.the_POAManager().activate();
// create servant and register it with the ORB
NorthBoundInterfaceImpl nbiImpl = new NorthBoundInterfaceImpl();
nbiImpl.setORB(orb);
// create a tie, with servant being the delegate.
NorthBoundInterfacePOATie tie = new NorthBoundInterfacePOATie(nbiImpl, rootpoa);
// obtain the objectRef for the tie
NorthBoundInterface nbi = tie._this(orb);
// get the root naming context
org.omg.CORBA.Object objRef = orb.resolve_initial_references("NameService");
// Naming Service specification.
NamingContextExt ncRef = NamingContextExtHelper.narrow(objRef);
// bind the Object Reference in Naming
String name = "NorthBoundInterface";
NameComponent path[] = ncRef.to_name( name );
ncRef.rebind(path, nbi);
System.out.println("NorthBoundInterface ready and waiting ...");
// wait for invocations from clients
orb.run();
catch (Exception e){
System.err.println("ERROR: " + e);
e.printStackTrace(System.out);
//CLIENT CODE
import corbatest.*;
import org.omg.CosNaming.*;
import org.omg.CosNaming.NamingContextPackage.*;
import org.omg.CORBA.*;
import org.omg.PortableServer.*;
import org.omg.PortableServer.POA;
import java.util.Properties;
public class Client{
     public static void main(String args[]){
     try{
     // create and initialize the ORB
          Properties properties = new Properties();
          properties.put("org.omg.CORBA.ORBInitialPort", "1050");
          properties.put("org.omg.CORBA.ORBInitialHost", "localhost");
          ORB orb = ORB.init((String[])null, properties);
     // get the root naming context
     org.omg.CORBA.Object objRef =
          orb.resolve_initial_references("NameService");
     NamingContextExt ncRef = NamingContextExtHelper.narrow(objRef);
     // resolve the Object Reference in Naming
     String name = "NorthBoundInterface";
     NorthBoundInterface nbi = NorthBoundInterfaceHelper.narrow(ncRef.resolve_str(name));
     System.out.println("Obtained a handle on server object: " + nbi);
     //CRASH HERE
     Device_CI device = nbi.GetDevice(44);
     int x = device.deviceID();
     catch (Exception e) {
     System.out.println("ERROR : " + e) ;
     e.printStackTrace(System.out);
RROR : org.omg.CORBA.UNKNOWN: ----------BEGIN server-side stack trace----------
org.omg.CORBA.UNKNOWN: vmcid: SUN minor code: 202 completed: Maybe
     at com.sun.corba.se.impl.logging.ORBUtilSystemException.runtimeexception(Unknown Source)
     at com.sun.corba.se.impl.protocol.CorbaMessageMediatorImpl.convertThrowableToSystemException(Unknown Source)
     at com.sun.corba.se.impl.protocol.CorbaMessageMediatorImpl.handleThrowableDuringServerDispatch(Unknown Source)
     at com.sun.corba.se.impl.protocol.CorbaMessageMediatorImpl.handleThrowableDuringServerDispatch(Unknown Source)
     at com.sun.corba.se.impl.protocol.CorbaServerRequestDispatcherImpl.dispatch(Unknown Source)
     at com.sun.corba.se.impl.protocol.CorbaMessageMediatorImpl.handleRequestRequest(Unknown Source)
     at com.sun.corba.se.impl.protocol.CorbaMessageMediatorImpl.handleRequest(Unknown Source)
     at com.sun.corba.se.impl.protocol.CorbaMessageMediatorImpl.handleInput(Unknown Source)
     at com.sun.corba.se.impl.protocol.giopmsgheaders.RequestMessage_1_2.callback(Unknown Source)
     at com.sun.corba.se.impl.protocol.CorbaMessageMediatorImpl.handleRequest(Unknown Source)
     at com.sun.corba.se.impl.transport.SocketOrChannelConnectionImpl.dispatch(Unknown Source)
     at com.sun.corba.se.impl.transport.SocketOrChannelConnectionImpl.doWork(Unknown Source)
     at com.sun.corba.se.impl.orbutil.threadpool.ThreadPoolImpl$WorkerThread.run(Unknown Source)
Caused by: java.lang.NullPointerException
     at org.omg.PortableServer.Servant._this_object(Unknown Source)
     at corbatest.Device_CIPOA._this(Device_CIPOA.java:68)
     at NorthBoundInterfaceImpl.GetDevice(NorthBoundInterfaceImpl.java:15)
     at corbatest.NorthBoundInterfacePOATie.GetDevice(NorthBoundInterfacePOATie.java:39)
     at corbatest.NorthBoundInterfacePOA._invoke(NorthBoundInterfacePOA.java:38)
     at com.sun.corba.se.impl.protocol.CorbaServerRequestDispatcherImpl.dispatchToServant(Unknown Source)
     ... 9 more
----------END server-side stack trace---------- vmcid: SUN minor code: 202 completed: Maybe

Answer 1

You have 2 sets of errors, at least.
The first is : Exception in thread "main" java.lang.NoClassDefFoundError: java/util/HashSet which is that you have not imported the class for hashset.
The second is that the import of the jars is probably wrong, hard to say without seeing code.