Java RMI，服务器如何管理异常客户端关机，何时不调用任何客户端方法？

I'm developing a application using Java RMI which enable clients to register topics they want to listen (zero or more) and topic (zero or one) they want to speak about. There is a central server which offers registration service. The communication of clients avoids server with the exception of initial registering of ListenerCallback or SpeakerCallback. Clients and server work according to Observer pattern.I'm developing a application using Java RMI whi