Hi,
I am trying to implement a simple shopping cart using stateful Session Bean.
I am passing an item from the client and bean is supposed to add this item in an ArrayList object and return this ArrayList object.
I don't know what's going wrong.

I am getting this error:

Adding item to cart
java.rmi.ServerException: RemoteException occurred in server thread; nested exception is:
 java.rmi.ServerException: RuntimeException; nested exception is:
 java.lang.ClassCastException
 at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:292)
 at sun.rmi.transport.Transport$1.run(Transport.java:148)
 at java.security.AccessController.doPrivileged(Native Method)
 at sun.rmi.transport.Transport.serviceCall(Transport.java:144)
 at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:460)
 at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:701)
 at java.lang.Thread.run(Thread.java:534)
 at sun.rmi.transport.StreamRemoteCall.exceptionReceivedFromServer(StreamRemoteCall.java:247)
 at sun.rmi.transport.StreamRemoteCall.executeCall(StreamRemoteCall.java:223)
 at sun.rmi.server.UnicastRef.invoke(UnicastRef.java:133)
 at org.jboss.invocation.jrmp.server.JRMPInvoker_Stub.invoke(Unknown Source)
 at org.jboss.invocation.jrmp.interfaces.JRMPInvokerProxy.invoke(JRMPInvokerProxy.java:135)
 at org.jboss.invocation.InvokerInterceptor.invoke(InvokerInterceptor.java:87)
 at org.jboss.proxy.TransactionInterceptor.invoke(TransactionInterceptor.java:46)
 at org.jboss.proxy.SecurityInterceptor.invoke(SecurityInterceptor.java:45)
 at org.jboss.proxy.ejb.StatefulSessionInterceptor.invoke(StatefulSessionInterceptor.java:104)
 at org.jboss.proxy.ClientContainer.invoke(ClientContainer.java:85)
 at $Proxy1.addToCart(Unknown Source)
 at cart.client.ShoppingCartClient.testBean(ShoppingCartClient.java:54)
 at cart.client.ShoppingCartClient.main(ShoppingCartClient.java:95)
Caused by: java.rmi.ServerException: RuntimeException; nested exception is:
 java.lang.ClassCastException
 at org.jboss.ejb.plugins.LogInterceptor.handleException(LogInterceptor.java:360)
 at org.jboss.ejb.plugins.LogInterceptor.invoke(LogInterceptor.java:195)
 at org.jboss.ejb.plugins.ProxyFactoryFinderInterceptor.invoke(ProxyFactoryFinderInterceptor.java:122)
 at org.jboss.ejb.StatefulSessionContainer.internalInvoke(StatefulSessionContainer.java:410)
 at org.jboss.ejb.Container.invoke(Container.java:674)
 at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
 at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
 at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
 at java.lang.reflect.Method.invoke(Method.java:324)
 at org.jboss.mx.capability.ReflectedMBeanDispatcher.invoke(ReflectedMBeanDispatcher.java:284)
 at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:549)
 at org.jboss.invocation.jrmp.server.JRMPInvoker.invoke(JRMPInvoker.java:359)
 at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
 at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
 at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
 at java.lang.reflect.Method.invoke(Method.java:324)
 at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:261)
 at sun.rmi.transport.Transport$1.run(Transport.java:148)
 at java.security.AccessController.doPrivileged(Native Method)
 at sun.rmi.transport.Transport.serviceCall(Transport.java:144)
 at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:460)
 at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:701)
 at java.lang.Thread.run(Thread.java:534)
Caused by: java.lang.ClassCastException
 at cart.sessionbean.MyCartEJBSession.getDao(MyCartEJBSession.java:44)
 at cart.sessionbean.MyCartEJBSession.addToCart(MyCartEJBSession.java:56)
 at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
 at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
 at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
 at java.lang.reflect.Method.invoke(Method.java:324)
 at org.jboss.ejb.StatefulSessionContainer$ContainerInterceptor.invoke(StatefulSessionContainer.java:878)
 at org.jboss.ejb.plugins.SecurityInterceptor.invoke(SecurityInterceptor.java:117)
 at org.jboss.resource.connectionmanager.CachedConnectionInterceptor.invoke(CachedConnectionInterceptor.java:186)
 at org.jboss.ejb.plugins.StatefulSessionInstanceInterceptor.invoke(StatefulSessionInstanceInterceptor.java:271)
 at org.jboss.ejb.plugins.AbstractTxInterceptor.invokeNext(AbstractTxInterceptor.java:84)
 at org.jboss.ejb.plugins.TxInterceptorCMT.runWithTransactions(TxInterceptorCMT.java:243)
 at org.jboss.ejb.plugins.TxInterceptorCMT.invoke(TxInterceptorCMT.java:104)
 at org.jboss.ejb.plugins.LogInterceptor.invoke(LogInterceptor.java:191)
 ... 21 more

package cart.client;

import java.rmi.RemoteException;
import java.util.Hashtable;
import java.util.ArrayList;
import javax.ejb.CreateException;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import javax.rmi.*;
import cart.sessionbean.dao.CartContents;
import cart.sessionbean.*;
/**
 * @author Abhishek
 *
 * To change the template for this generated type comment go to
 * Window>Preferences>Java>Code Generation>Code and Comments
 */
public class ShoppingCartClient {

 CartContents cartObject=new CartContents();
 ArrayList resultCart=new ArrayList();
 int size=0;

 private cart.sessionbean.MyCartEJBHome getHome() throws NamingException {
 Object ref= getContext().lookup(cart.sessionbean.MyCartEJBHome.JNDI_NAME);
 MyCartEJBHome mycart =(cart.sessionbean.MyCartEJBHome)PortableRemoteObject.narrow(ref,MyCartEJBHome.class);
 return mycart;
 }
 private InitialContext getContext() throws NamingException {
 Hashtable props = new Hashtable();

 props.put(
 InitialContext.INITIAL_CONTEXT_FACTORY,
 "org.jnp.interfaces.NamingContextFactory");
 props.put(InitialContext.PROVIDER_URL, "jnp://127.0.0.1:1099");

 InitialContext initialContext = new InitialContext(props);
 return initialContext;
 }
 public void testBean() {

 try {
 cart.sessionbean.MyCartEJB myBean = getHome().create(resultCart);

 //--------------------------------------
 //This is the place you make your calls.
 System.out.println("Adding item to cart");
 resultCart=myBean.addToCart("id001",1);
 System.out.println("Going to Sleep for 1 min ......................... " );
 Thread.sleep(60000); // sleep for 1 minute.
 //System.out.println("Reply from bean after 1min " + myBean.getMyCart());
 resultCart=myBean.getMyCart();
 size=resultCart.size();
 for(int i=0;i<size;i++)
 {
 cartObject=(CartContents)resultCart.get(i);
 System.out.println(cartObject.getItemid());
 System.out.println(cartObject.getQuantity());

 }

 System.out.println("Going to Sleep for 1 min ......................... " );
 Thread.sleep(60000);
 System.out.println("Adding item to cart");
 resultCart=myBean.addToCart("id002",2);
 resultCart=myBean.getMyCart();
 for(int i=0;i<size;i++)
 {
 cartObject=(CartContents)resultCart.get(i);
 System.out.println(cartObject.getItemid());
 System.out.println(cartObject.getQuantity());

 }

 } catch (RemoteException e) {
 e.printStackTrace();
 } catch (CreateException e) {
 e.printStackTrace();
 } catch (NamingException e) {
 e.printStackTrace();
 } catch (InterruptedException e)
 {

 }
 }

 public static void main(String[] args) {
 ShoppingCartClient test = new ShoppingCartClient();
 test.testBean();

 }
}