RMI 远程通信 demo

1、定义实体，实现序列化接口

public class User implements Serializable {

    private String username;

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }
}

2、定义接口和实现类

public interface IHelloService extends Remote {
    String sayHello(User user) throws RemoteException;
}

public class HelloServiceImpl extends UnicastRemoteObject implements IHelloService{

    protected HelloServiceImpl() throws RemoteException {
        super();
    }

    @Override
    public String sayHello(User user) throws RemoteException{
        System.out.println("this is server, say hello to " + user.getUsername());
        return "success";
    }
}

3、定义RMI服务端

public class RMIServer {
    public static void main(String[] args) throws RemoteException, AlreadyBoundException, MalformedURLException {
        //1、创建 HelloService 实例
        IHelloService service = new HelloServiceImpl();
        //2、获取注册表
        LocateRegistry.createRegistry(8888);
        //3、对象的绑定， 参数1：rmi//ip地址：端口/服务名 参数2：绑定的对象
        Naming.bind("//127.0.0.1:8888/rmiserver",service);
    }
}

4、定义客户端

public class RMIClient {
    public static void main(String[] args) throws RemoteException, NotBoundException, MalformedURLException {
        //1、从注册表中获取远程对象，强转
        IHelloService service = (IHelloService) Naming.lookup("//127.0.0.1:8888/rmiserver");
        //2、准备参数
        User user = new User();
        user.setUsername("jack");
        //3、调用远程方法 sayHello
        String message = service.sayHello(user);
        System.out.println(message);
    }
}