RMI client 'cannot cast to' exception

问题

Let's say I have these lines:

Registry registry = LocateRegistry.getRegistry(2121);
RemoteObject probe = (RemoteObject)registry.lookup(REMOTE_OBJ_NAME);//this throws exception
probe.doSomething();

The exception is this:

java.lang.ClassCastException: $Proxy1 cannot be cast to app.RemoteObject

For the sake of clarity, the RemoteObject implements an interface which extends java.rmi.Remote.

回答1:

you need to cast to interface that extended Remote

RemoteInterface probe = (RemoteInterface)registry.lookup(REMOTE_OBJ_NAME);
probe.doSomething(); 

this is because you never get the actual object back but a stub object that forwards any method calls to the actual object

回答2:

do not extends Remote if your class implements Serializable

来源：https://stackoverflow.com/questions/12496135/rmi-client-cannot-cast-to-exception