java rmi 使用方法

server

package Server;

import java.rmi.Naming;
import java.rmi.RMISecurityManager;
import java.rmi.registry.LocateRegistry;

import Service.Calc;
import ServiceImpl.CalcImpl;

public class Server{
     // 由于这里测试我们是最终用户，所以直接将异常抛给虚拟机
     public static void main(String[] args) throws Exception
     {
          System.setSecurityManager(new RMISecurityManager()); //权限
          System.setProperty("java.rmi.server.hostname","192.168.1.119");  //指定外网IP

          LocateRegistry.createRegistry(9000);
          //System.setProperty("java.security.policy", "/home/ufo/workspace_java/RMIServer/Calc.policy");
          Calc c = new CalcImpl(); 

          Naming.rebind("rmi://192.168.1.119:9000/Calc", c); 

          System.out.println("rmi server start ...");
     }
}

service

package Service;

import java.rmi.*;

public interface Calc extends Remote {
	public int add(int x,int y) throws RemoteException;
}

　　service impl

package ServiceImpl;

import java.rmi.RemoteException;
import java.rmi.server.UnicastRemoteObject;

import Service.Calc;

public class CalcImpl extends UnicastRemoteObject implements Calc{

	/**
	 *
	 */
	private static final long serialVersionUID = 6523564220840187253L;

	public CalcImpl() throws RemoteException {
		super();
		// TODO Auto-generated constructor stub
	}

	@Override
	public int add(int x, int y) {
		// TODO Auto-generated method stub
		System.out.println("add called!");
		return x+y;
	}

}

client

package client;

import java.rmi.*;
import java.net.MalformedURLException;
import Service.Calc;

public class Client
{
    // 同样为了方便，直接异常抛出
    public static void main(String[] args) throws Exception
    {
        System.setSecurityManager(new RMISecurityManager());
        try
        {
            // 这里因为是在本地所以省略了地址跟协议，若在网络中的远程方法调用，需要这样写
            // Converter c = (Converter)Naming.lookup("rmi://192.168.0.13/convert");
            Calc c = (Calc)Naming.lookup("rmi://192.168.1.119:9000/Calc");
            int rmb = c.add(10,20);
            System.out.println("add result : " + rmb);
        }
        catch (MalformedURLException e)
        {
            e.printStackTrace();
        }
        catch (RemoteException e)
        {
            e.printStackTrace();
        }
        catch (NotBoundException e)
        {
            e.printStackTrace();
        }
    }
}

客户端和服务器端都需要制定 类权限文件,即启动时命令  java -Djava.security.policy=./Calc.policy   server.Server[client.Client]

Calc.policy

grant {
permission java.security.AllPermission;
};

客户端还需要有服务的接口声明