RMI学习笔记-创建第一个RMI应用

 学习使用RMI框架，抄写了一段例子代码：

     代码如下：

package com.you.rmi;

import java.rmi.Remote;
import java.rmi.RemoteException;
import java.rmi.registry.LocateRegistry;
import java.rmi.server.UnicastRemoteObject;
import java.util.Date;

import javax.naming.Context;
import javax.naming.InitialContext;



public class SimpleServer  {
	public static void main(String[] args) {

		try {
			HelloService service1 = new HelloServiceImpl("service1");
			HelloService service2 = new HelloServiceImpl("service2");
			Context namingContext = new InitialContext();
			
			LocateRegistry.createRegistry(1099);
			namingContext.rebind("rmi://localhost:1099/HelloService1", service1);//rebind注册对象，把对象与一个名字
        	namingContext.rebind("rmi://localhost:1099/HelloService2", service2);//绑定，如果改名字已经被绑定，不过抛出异常
			System.out.println("服务器注册了两个HelloService对象");
		} catch (Exception e) {
			e.printStackTrace();
		}
		
	}

}

interface HelloService extends Remote{
	   public String echo(String msg) throws RemoteException;
	   public Date getTime() throws RemoteException;
}

class HelloServiceImpl extends UnicastRemoteObject implements HelloService{
     /**
	 * 
	 */
	private static final long serialVersionUID = 1L;
	private String name;
     public HelloServiceImpl(String name) throws RemoteException{
    	 this.name = name;
     }
	@Override
	public String echo(String msg) {
		System.out.println(name + "调用echo()方法");
		return "echo:" + msg + "from" + name;
	}

	@Override
	public Date getTime() {
		System.out.println(name + "调用getTime（）方法");
		return new Date();
	}
	

}

 package com.you.rmi; 

import java.rmi.RemoteException;

import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NameClassPair;
import javax.naming.NamingEnumeration;
import javax.naming.NamingException;

public class SimpleClient {
	public static void showRemoteObjects(Context namingContext) throws Exception {
		NamingEnumeration<NameClassPair> e = namingContext.list("rmi:");
		while(e.hasMore())
			System.out.println(e.next().getName());
	}
	
	public static void main(String[] args) {
		try {
			String url = "rmi://localhost/";
			Context namingContext = new InitialContext();
			//获得远程对象的存根对象
			HelloService service1 = (HelloService) namingContext.lookup(url + "HelloService1");
			HelloService service2 = (HelloService) namingContext.lookup(url + "HelloService2");
			
			//测试存根对象所属的类
			Class stubClass = service1.getClass();
			System.out.println("service1 是" + stubClass.getName() + "的实例");
			Class[] interfaces = stubClass.getInterfaces();
			for(int i = 0; i < interfaces.length; i++) {
				System.out.println("存根类实现了" + interfaces[i].getName());
				
			System.out.println(service1.echo("hello"));
			System.out.println(service1.getTime());
			
			System.out.println(service2.echo("hello"));
			System.out.println(service2.getTime());
			
			showRemoteObjects(namingContext);
			}
			
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}

}

 java进阶网在例子中没有LocateRegistry.createRegistry(1099);这句代码，一开始运行的时候，总是报错，报服务器拒绝连接的错误，加上这句话就运行成功了，虽然rmi的默认端口是1099，但是需要告诉服务器一声，不然服务器不会得到通知，拒绝连接  。