rpc 远程方法调用实例

题目：

完成以下的功能：服务端有一个计算器，有加减两个方法，分别为：add(p1,p2),minus(p1,p2)。

创建Request类实现序列化接口，该类包含以下属性：

String methodName;//方法名

Object[] params;//方法参数列表。

将客户端发送method,p1,p2到服务端请求封装成request发到服务端。

服务端响应请求,将结果封装成response发送给客户端

Response 属性如下：

Object result;//方法调用结果

String msg;//成功则为success,是否则为failure;

思路：运用rpc 远程方法调用 包括动态代理、网络、序列化、反射

代码如下

package Test;

import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.net.ServerSocket;
import java.net.Socket;

public class MyServer {
    public static void main(String[] args) throws IOException, ClassNotFoundException, InvocationTargetException, IllegalAccessException {
        //开启9999监听端口进行监听
        ServerSocket serverSocket = new ServerSocket(9999);
        //监听客户端的连接
        Socket client = serverSocket.accept();
        //创建用于接收客户端的对象输出和输入流--用于反序列化
        ObjectOutputStream oos = new ObjectOutputStream(client.getOutputStream());
        ObjectInputStream ois = new ObjectInputStream(client.getInputStream());
        //接收客户端传过来的请求
        Request request = (Request) ois.readObject();
        //
        String methodName = request.getMethodName();
        Object[] params = request.getParams();
        //反射--第一步：获取类
        Class<MyCalculatorImpl> clazz = MyCalculatorImpl.class;
        //由类名获取所有方法
        Method[] methods = clazz.getDeclaredMethods();
        //遍历方法数组
        for (Method method :
                methods) {
            //判断方法数组中名字是否有请求中的方法名
            if (method.getName().equals(methodName)) {
                //如果有则用该方法调用invoke方法--类似于创建一个MyCalculatorImpl对象调用该方法
                Object res = method.invoke(new MyCalculatorImpl(), params);
                Response response = new Response();
                response.setRes(res);
                response.setMag("success");
                oos.writeObject(response);
            }
        }
    }
}

package Test;

import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.net.Socket;

//客户端
public class MyClient {
    public static void main(String[] args) throws IOException, ClassNotFoundException {
        Socket socket = new Socket("127.0.0.1", 9999);
        final ObjectInputStream ois = new ObjectInputStream(socket.getInputStream());
        final ObjectOutputStream oos = new ObjectOutputStream(socket.getOutputStream());
        //类加载器
        ClassLoader classLoader = MyClient.class.getClassLoader();
        //定义一个接口
        Class[] interfaces = {MyCalculator.class};
        //创建一个代理处理类
        InvocationHandler invocationHandler = new InvocationHandler() {
            public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
                String name = method.getName();
                Request request = new Request();
                request.setMethodName(name);
                request.setParams(args);
                //发送出去
                oos.writeObject(request);
                //接收响应
                Response response = (Response) ois.readObject();
                return response.getRes();
            }
        };
        //生成一个真正的代理类
        MyCalculator mycal = (MyCalculator) Proxy.newProxyInstance(classLoader, interfaces, invocationHandler);
        int res2 = mycal.minus(15, 7);
        System.out.println(res2);
        /*Request request = new Request();
        request.setMethodName("add");
        request.setParams(new Object[]{1,3});
        oos.writeObject(request);
        Response response = (Response) ois.readObject();
        System.out.println(response);*/
    }
}

package Test;
//客户端的计算器接口
public interface MyCalculator {
    int add(int p1, int p2);
    int minus(int p1, int p2);
}

package Test;

//用作反射--服务器的计算器
//Impl是一个实现了某个接口的实现类
public class MyCalculatorImpl implements MyCalculator{
    public int add(int p1, int p2) {
        return p1 + p2;
    }
    public int minus(int p1, int p2) {
        return p1 - p2;
    }
}

package Test;

import java.io.Serializable;
//Request请求对象：方法名+方法参数
public class Request implements Serializable {
    //方法名
    private String methodName;
    //方法参数数组
    private Object[] params;

    public String getMethodName() {
        return methodName;
    }

    public void setMethodName(String methodName) {
        this.methodName = methodName;
    }

    public Object[] getParams() {
        return params;
    }

    public void setParams(Object[] params) {
        this.params = params;
    }
}

package Test;

import java.io.Serializable;
//服务器给客户端的响应对象：结果+标示
public class Response implements Serializable {
    //结果
    private Object res;
    //标示
    private String mag;

    public Object getRes() {
        return res;
    }

    public void setRes(Object res) {
        this.res = res;
    }

    public String getMag() {
        return mag;
    }

    public void setMag(String mag) {
        this.mag = mag;
    }

    @Override
    public String toString() {
        return "Response{" +
                "res=" + res +
                ", mag='" + mag + '\'' +
                '}';
    }
}