230105_05_RPC底层原理

• 返回值一定是一个对象，当前是把user拆分成1个id，1个name返回，当user变了，比如增加了属性，则需要再次修改相应代码，因此需要进一步优化
• 直接将这个对象返回，不进行拆分
• Stub:返回值封装成Object对象

package com.bill.rpc05;

import com.bill.rpc.common.IUserService;
import com.bill.rpc.common.User;

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;

/**
 * @Auther: wangchunwen
 * @Date: 2023/1/5 - 01 - 05 - 23:15
 * @Description: com.bill.rpc05
 * @version: 1.0
 */
public class Stub {
    public static IUserService getStub(){
        InvocationHandler h = new InvocationHandler() {
            public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
                Socket s = new Socket("127.0.0.1",8888);

                ObjectOutputStream oos = new ObjectOutputStream(s.getOutputStream());

                String methodName = method.getName();
                Class[] parametersTypes = method.getParameterTypes();
                oos.writeUTF(methodName);
                oos.writeObject(parametersTypes);
                oos.writeObject(args);
                oos.flush();

                ObjectInputStream ois = new ObjectInputStream(s.getInputStream());
                User user = (User) ois.readObject();

                oos.close();
                s.close();
                return user;

            }
        };
        Object o = Proxy.newProxyInstance(IUserService.class.getClassLoader(),new Class[] {IUserService.class},h);
        System.out.println(o.getClass().getName());
        System.out.println(o.getClass().getInterfaces()[0]);
        return (IUserService)o;
    }
}

• server

package com.bill.rpc05;

import com.bill.rpc.common.IUserService;
import com.bill.rpc.common.User;
import com.bill.rpc01.UserServiceImpl;

import java.io.*;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.net.ServerSocket;
import java.net.Socket;

/**
 * @Auther: wangchunwen
 * @Date: 2023/1/5 - 01 - 05 - 23:14
 * @Description: com.bill.rpc05
 * @version: 1.0
 */
public class Server {
    private static boolean running = true;

    public static void main(String[] args) throws IOException, ClassNotFoundException, NoSuchMethodException, IllegalAccessException, InvocationTargetException {
        ServerSocket ss = new ServerSocket(8888);
        while (running){
            Socket s = ss.accept();
            process(s);
            s.close();
        }
        ss.close();
    }

    private static void process(Socket s) throws IOException, ClassNotFoundException, NoSuchMethodException, InvocationTargetException, IllegalAccessException {
        InputStream in = s.getInputStream();
        OutputStream out = s.getOutputStream();
        ObjectInputStream ois = new ObjectInputStream(in);


        String methodName = ois.readUTF();
        Class[] parameterTypes = (Class[]) ois.readObject();
        Object[] args = (Object[]) ois.readObject();

        IUserService service = new UserServiceImpl();
        Method method = service.getClass().getMethod(methodName,parameterTypes);
        User user = (User) method.invoke(service,args);

        ObjectOutputStream oos = new ObjectOutputStream(out);
        oos.writeObject(user);

        oos.flush();
    }
}