Java基础网络编程ServerClient通信（3）

package com.hspedu.net_;

import org.junit.Test;

import java.io.*;
import java.net.ServerSocket;
import java.net.Socket;

public class MyServer {

    @Test
    public void startMyServer() throws IOException {
        ServerSocket serverSocket = new ServerSocket(8080);
        System.out.println("服务器server正在监听8080端口...");
        Socket socket = serverSocket.accept();


        // 1.server使用转换流InputStreamReader接收client发送的消息
        InputStream inputStream = socket.getInputStream();
        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream));
        String lineData;
        while ((lineData = bufferedReader.readLine()) != null) {
            System.out.println(lineData);
        }


        // 2.server使用转换流OutputStreamWriter回复消息给client
        OutputStream outputStream = socket.getOutputStream();
        BufferedWriter bufferedWriter = new BufferedWriter(new OutputStreamWriter(outputStream));
        bufferedWriter.write("服务器 >>> 客户端：hello, client.");
        bufferedWriter.newLine();
        bufferedWriter.write("哈哈哈hhh");
        bufferedWriter.newLine();
        bufferedWriter.flush();
        socket.shutdownOutput();

        bufferedReader.close();
        bufferedWriter.close();
        socket.close();
        serverSocket.close();
    }
}

1、使用bufferedWriter输出流必须手动调用flush方法刷新，使数据可以进入传输通道；

2、服务器server使用io回复消息必须使用socket.shutdownOutput写入结束标记，否则服务器server会认为还有数据要输出，客户端client会认为还有数据要读取，server和client都会阻塞；

package com.hspedu.net_;

import org.junit.Test;

import java.io.*;
import java.net.InetAddress;
import java.net.Socket;
import java.net.UnknownHostException;

/**
 * 转换流OutputStreamWriter、InputStreamReader实现server和client通信
 */
public class MyClient {

    @Test
    public void startMyClient() throws IOException {
        Socket socket = new Socket(InetAddress.getLocalHost(), 8080);

        // 输出流
        OutputStream outputStream = socket.getOutputStream();
        BufferedWriter bufferedWriter = new BufferedWriter(new OutputStreamWriter(outputStream));
        bufferedWriter.write("客户端 >>> 服务器：hello, server。");
        bufferedWriter.newLine();
        bufferedWriter.write("这是一条信息abc。");
        bufferedWriter.newLine();
        bufferedWriter.write("这是另一条信息123。");
        bufferedWriter.newLine();
        bufferedWriter.flush();
        socket.shutdownOutput();

        // 输入流：接收server回复的消息
        InputStream inputStream = socket.getInputStream();
        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream));
        String lineData;

        while ((lineData = bufferedReader.readLine()) != null) {
            System.out.println(lineData);
        }

        // 关闭资源
        bufferedWriter.close();
        bufferedReader.close();
        socket.close();
    }
}

1、client同理也需要手动调用刷新flush方法；

2、关闭socket的输出流的标记。