一個簡單的HELLO程序

Hello.java:

import java.rmi.Remote;
import java.rmi.RemoteException;

public interface Hello extends Remote {
    String sayHello() throws RemoteException;
}

Client.java:

import java.rmi.registry.LocateRegistry;
import java.rmi.registry.Registry;

public class Client {

    private Client() {}

    public static void main(String[] args) {

 String host = (args.length < 1) ? null : args[0];
 try {
     //注冊指定的主機,沒有指定就是本地主機
     Registry registry = LocateRegistry.getRegistry(host);
     //取得主機打開的服務接口
     Hello stub = (Hello) registry.lookup("Hello");
     String response = stub.sayHello();
     System.out.println("response: " + response);
 } catch (Exception e) {
     System.err.println("Client exception: " + e.toString());
     e.printStackTrace();
 }
    }
}

Server.java:

import java.rmi.registry.Registry;
import java.rmi.registry.LocateRegistry;
import java.rmi.RemoteException;
import java.rmi.server.UnicastRemoteObject;
 
public class Server implements Hello {
 
    public Server() {}

    public String sayHello() {
 return "Hello, world!";
    }
 
    public static void main(String args[]) {
 
 try {
     Server obj = new Server();
     Hello stub = (Hello) UnicastRemoteObject.exportObject(obj, 0);

     // Bind the remote object's stub in the registry
     Registry registry = LocateRegistry.getRegistry();
     registry.bind("Hello", stub);

     System.err.println("Server ready");
 } catch (Exception e) {
     System.err.println("Server exception: " + e.toString());
     e.printStackTrace();
 }
    }
}

工作流程圖:

 

 

Hello的客戶端工作流程

 

注冊遠程服務器

Registry registry=LocateRegistry.getRegistry();

以字符串的形式獲得遠程服務器的服務

Hello stub=(Hello)registry.lookup("Hello");

用取得的服務去調用遠程服務器的方法

String response=stub.sayHello();

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

使用JRMP（Java 遠程方法協議）用于導出一個遠程對象，并且獲得一個與遠程對象通信的stub

Hello stub=(Hello)UnicastRemoteObject.exportObject(obj,0);

注冊服務器

Registry registry=LocateRegistry.getRegistry();

將名字綁定到遠程通信的stub上，并且注冊

registry.bind("Hello",stub);

Hello的服務端工作流程