IllegalAccessError passing object with RMI

Question

Hi,
I am playing with RMI at the moment.
I have a Remote class that implements a Remote interface
The interface has one method which the class implements and this is to get a TestSerial object.
If I run without using a Securitymanager then there are no problems.
When I do use the SecurityManager then there is an error.
This error remains even if set the permissions in the policy file to java.security.AllPermissions
Does anyone know why this is?
thanks in advance,
J
//Start the server....
java -Djava.security.policy=policy HelloServer
In main....
HelloImpl bound in registry....
//Run the client
java -Djava.security.policy=policy HelloClient
Exception in thread "main" java.lang.IllegalAccessError: tried to access TestSerial from class $Proxy0
at $Proxy.getTestSerial(Unknown Source)
     at HelloClient.main(HelloClient.jav:23)
* Remote interface
public interface Hello extends java.rmi.Remote {
    TestSerial getTestSerial() throws java.rmi.RemoteException;
* Remote class
public class HelloImpl implements Hello {
  public HelloImpl() {
  public TestSerial getTestSerial(){
    return new TestSerial();
* Server class
import java.io.*;
import java.rmi.*;
import java.rmi.server.*;
import java.rmi.registry.*;
public class HelloServer {
  public HelloServer() {
  public static void main(String args[]) {
    System.out.println("In main....");
    if (System.getSecurityManager() == null) {
      System.setSecurityManager(new SecurityManager());
    try {
      HelloImpl obj = new HelloImpl();
      Hello stub = (Hello) UnicastRemoteObject.exportObject(obj, 0);
      Registry registry = LocateRegistry.createRegistry(Registry.REGISTRY_PORT);
      registry.bind("Hello", stub);
      System.out.println("HelloImpl bound in registry...."); 
    catch (Exception e) {
      System.out.println("HelloImpl exception: " + e.getMessage());
      e.printStackTrace();
* Client class
import java.rmi.*;
import java.rmi.registry.*;
import java.io.*;
public class HelloClient {
public static void main(String args[]) {
   if (System.getSecurityManager() == null) {
     System.setSecurityManager(new SecurityManager());
   try {
      Registry registry = LocateRegistry.getRegistry();
      Hello obj = (Hello) registry.lookup("Hello");
      TestSerial x = obj.getTestSerial();
      System.out.println(x.getName());
    catch (Exception e) {
      System.out.println("HelloClient exception: " + e.printStackTrace();
* TestSerial class
class TestSerial implements java.io.Serializable {
  public TestSerial(){
  public String getName(){
    return "TestSerial";
* Policy file
grant codeBase "file:." {
  permission java.net.SocketPermission "*:1024-", "accept,connect";
};

Answer 1

class TestSerial implements java.io.Serializable {
public class TestSerial implements java.io.Serializable {