230102_50_RPC底层原理

package com.bill.rpc01;

import com.bill.rpc.common.User;

import java.io.ByteArrayOutputStream;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.net.Socket;

/**
 * @Auther: wangchunwen
 * @Date: 2023/1/2 - 01 - 02 - 22:31
 * @Description: com.bill.rpc01
 * @version: 1.0
 */
public class Client {
    public static void main(String[] args) throws IOException {
        // 写出去
        Socket s = new Socket("127.0.0.1",8888);
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        DataOutputStream dos = new DataOutputStream(baos);
        dos.writeInt(123);

        s.getOutputStream().write(baos.toByteArray());
        s.getOutputStream().flush();

        // 读进来
        DataInputStream dis = new DataInputStream(s.getInputStream());
        int id = dis.readInt();
        String name = dis.readUTF();
        User user = new User(id,name);

        System.out.println(user);

        dos.close();
        s.close();
    }
}

将网络通信的工作抽离出来，单独抽象为一个类，这个类的作用就是相当于1个网络通信的一个代理，屏蔽了一些网络通信实现的相关的细节。

package com.bill.rpc02;

import com.bill.rpc.common.User;

import java.io.ByteArrayOutputStream;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.net.Socket;

/**
 * @Auther: wangchunwen
 * @Date: 2023/1/2 - 01 - 02 - 22:42
 * @Description: com.bill.rpc02
 * @version: 1.0
 */
public class Stub {
    public User findUser(Integer id) throws IOException {
        Socket s = new Socket("127.0.0.1",8888);
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        DataOutputStream dos = new DataOutputStream(baos);
        dos.writeInt(123);
        
        s.getOutputStream().write(baos.toByteArray());
        s.getOutputStream().flush();

        DataInputStream dis = new DataInputStream(s.getInputStream());
        int receivedId = dis.readInt();
        String name = dis.readUTF();
        User user = new User(receivedId,name);
        
        dos.close();
        dos.close();
        
        return user;
        
    }
}