CommunicationException- failed to unmarshel Remote business interface looking up ejb3 in weblogic - interface

Question

My ejb 3 classes and remote interface are as follows :
package com.myeclipse.ejb3;
import java.io.Serializable;
public interface IMyBean extends Serializable
{
public void doSomething();
}
Remote interface:
package com.myeclipse.ejb3;
import javax.ejb.Remote;
#Remote
public interface MyBeanRemote extends IMyBean {
}
Stateless ejb:
package com.myeclipse.ejb3;
import javax.ejb.Stateless;
#Stateless(mappedName="ejb/MyBean")
public class MyBean implements MyBeanRemote
{
public void doSomething()
{
System.out.println("Hello world");
}
}
Project is successully deployed as a jar file in weblogic. I developed
a standalone client to call ejb. But this is failing. Kindly help.
I've included all the weblogic server libraries to connect to jndi and
remote business interface for complilation.
Client Code :
package Ejb3_Client;
import java.util.Properties;
import javax.naming.InitialContext;
import javax.naming.NamingException;
public class MyBeanClient {
/**
* #param args
*/
public static void main(String[] args)
{
// TODO Auto-generated method stub
try {
Properties p = new Properties();
p.put("java.naming.factory.initial", "weblogic.jndi.WLInitialContextFactory");
p.put("java.naming.provider.url", "t3://172.21.123.70:8001");
InitialContext ctx = new InitialContext(p);
MyBeanRemote bean = (MyBeanRemote) ctx.lookup("ejb/MyBean#com.myeclipse.ejb3.MyBeanRemote");
System.out.println("bean instance "+ bean);
bean.doSomething();
System.out.println("bean worked");
} catch (NamingException e) {
e.printStackTrace();
}
}
}
But I am getting this exception:
javax.naming.CommunicationException [Root exception is
java.rmi.UnmarshalException: failed to unmarshal class
java.lang.Object; nested exception is:
java.lang.ClassNotFoundException: com.myeclipse.ejb3.MyBeanRemote]
at
weblogic.jndi.internal.ExceptionTranslator.toNamingException(ExceptionTranslator.java:74)
at
weblogic.jndi.internal.WLContextImpl.translateException(WLContextImpl.java:439)
at
weblogic.jndi.internal.WLContextImpl.lookup(WLContextImpl.java:395)
at
weblogic.jndi.internal.WLContextImpl.lookup(WLContextImpl.java:380)
at javax.naming.InitialContext.lookup(InitialContext.java:392) at
Ejb3_Client.MyBeanClient.main(MyBeanClient.java:33) Caused by:
java.rmi.UnmarshalException: failed to unmarshal class
java.lang.Object; nested exception is:
java.lang.ClassNotFoundException: com.myeclipse.ejb3.MyBeanRemote at
weblogic.rjvm.ResponseImpl.unmarshalReturn(ResponseImpl.java:244) at
weblogic.rmi.cluster.ClusterableRemoteRef.invoke(ClusterableRemoteRef.java:348)
at
weblogic.rmi.cluster.ClusterableRemoteRef.invoke(ClusterableRemoteRef.java:259)
at weblogic.jndi.internal.ServerNamingNode_1030_WLStub.lookup(Unknown
Source) at
weblogic.jndi.internal.WLContextImpl.lookup(WLContextImpl.java:392)
... 3 more Caused by: java.lang.ClassNotFoundException:
com.myeclipse.ejb3.MyBeanRemote at
java.net.URLClassLoader$1.run(URLClassLoader.java:200) at
java.security.AccessController.doPrivileged(Native Method) at
java.net.URLClassLoader.findClass(URLClassLoader.java:188) at
java.lang.ClassLoader.loadClass(ClassLoader.java:307) at
sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301) at
java.lang.ClassLoader.loadClass(ClassLoader.java:252) at
weblogic.ejb.container.internal.RemoteBusinessIntfProxy.readObject(RemoteBusinessIntfProxy.java:200)
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:597) at
java.io.ObjectStreamClass.invokeReadObject(ObjectStreamClass.java:974)
at
java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1849)
at
java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1753)
at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
at
java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1947)
at
java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1871)
at
java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1753)
at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
at java.io.ObjectInputStream.readObject(ObjectInputStream.java:351)
at
weblogic.utils.io.ChunkedObjectInputStream.readObject(ChunkedObjectInputStream.java:197)
at
weblogic.rjvm.MsgAbbrevInputStream.readObject(MsgAbbrevInputStream.java:564)
at
weblogic.utils.io.ChunkedObjectInputStream.readObject(ChunkedObjectInputStream.java:193)
at weblogic.rmi.internal.ObjectIO.readObject(ObjectIO.java:62) at
weblogic.rjvm.ResponseImpl.unmarshalReturn(ResponseImpl.java:240) ...
7 more
I searched a lot but din find the problem why it can't unmarshel remote interface.

Answer 1

the reason for above error mainly because in some java file which implements Serializable interface has been changed you can revert those files to previous version