Serialize MBeanServerConnection in order to be returned by an RMI's remote method

Question

I have an RMI's remote interface:

public interface JMXManager extends Remote {

    public MFSMBeanServerConnection getMBeanServerConnection(String className)
            throws RemoteException;
    }
}

MFSMBeanServerConnection and MFSMBeanServerConnectionImpl that I created in order to serialize MBeanServerConnection:

public interface MFSMBeanServerConnection extends Serializable {
     public MBeanServerConnection getMBeanServerConnection();
}

public class MFSMBeanServerConnectionImpl implements MFSMBeanServerConnection {

    private static final long serialVersionUID = 1006978249744538366L;
    /**
     * @serial
     */
    private MBeanServerConnection mBeanServerConnection;

    public MFSMBeanServerConnectionImpl() {}

    public MFSMBeanServerConnectionImpl(MBeanServerConnection mBeanServerConnection) {
        this.mBeanServerConnection = mBeanServerConnection;
    }

    public MBeanServerConnection getMBeanServerConnection() {
        return mBeanServerConnection;
    }

    private void readObject(ObjectInputStream aInputStream) throws ClassNotFoundException,
            IOException {
        aInputStream.defaultReadObject();
        mBeanServerConnection = (MBeanServerConnection) aInputStream.readObject();
    }

    private void writeObject(ObjectOutputStream aOutputStream) throws IOException {
        aOutputStream.defaultWriteObject();
        aOutputStream.writeObject(mBeanServerConnection);
    }

    private void readObjectNoData() throws ObjectStreamException {

    }
}

On the client side I have

JMXManager jmxm= (JMXManager) registry.lookup("JMXManager");  
MFSMBeanServerConnection mfsMbsc = jmxm.getMBeanServerConnection(className);

on the second line I get an Exception:

java.rmi.UnmarshalException: error unmarshalling return; nested exception is: 
java.io.WriteAbortedException: writing aborted; java.io.NotSerializableException: javax.management.remote.rmi.RMIConnector$RemoteMBeanServerConnection
at sun.rmi.server.UnicastRef.invoke(UnicastRef.java:173)
at java.rmi.server.RemoteObjectInvocationHandler.invokeRemoteMethod(RemoteObjectInvocationHandler.java:178)
at java.rmi.server.RemoteObjectInvocationHandler.invoke(RemoteObjectInvocationHandler.java:132)
at $Proxy0.getMBeanServerConnection(Unknown Source)

My goal is to create an RMI Server that:

• is used by one or more JMX servers which store their MBeanServerConnection
• a client takes one MBeanServerConnection and use (manipulate) its MBeans

What I am doing wrong? How can I serialze javax.management.MBeanServerConnection so that I can use it with an remote interface?

Answer 1

I think its a bad idea to Serialize MBeanServerConnection because it is supposed to store a lot of Run Time Information/Some information which will not be available or valid when you deserialize it.

It think that is reason that all its known SubInterfaces ( MBeanServer, MBeanServerForwarder) also do not implement Serializable.