Java Socket通信实例

一、简单的客户端与服务器一对一连接：

Socket通信的步骤：

1、创建ServerSocket和Socket

2、打开连接到Scket的输入/输出流

3、按照协议对Socket进行读/写操作

4、关闭输入输出流、关闭Socket

废话不多说，直接上代码，服务端和客户端的注释写的很清楚！！！

package com.socket;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;

public class Server {
    public static void main(String[] args) {
        try {
            // 1.创建服务器端Socket对象，绑定并监听窗口
            ServerSocket serverSocket = new ServerSocket(8888);
            System.out.println("服务器已启动，等待客户端连接...");
            // 2.调用accept()方法开始监听，等待客户端连接
            Socket socket = serverSocket.accept();
            // 3.获取输入流，并读取客户端信息
            InputStream inputStream = socket.getInputStream();
            InputStreamReader inputStreamReader = new InputStreamReader(inputStream);// 将字节流转换为字符流
            BufferedReader bufferedReader = new BufferedReader(inputStreamReader);
            String temp = null;
            String info = "";
            while ((temp = bufferedReader.readLine()) != null) {
                info += temp;
                System.out.println("已收到客户端连接");
                System.out.println("服务端接收到客户端信息：" + info + "当前客户端ip:" + socket.getInetAddress().getHostAddress());
            }
            // 4.获取输出流，响应客户端的请求
            OutputStream outputStream = socket.getOutputStream();
            PrintWriter printWriter = new PrintWriter(outputStream);
            printWriter.print("你好服务端已收到您的信息");
            printWriter.flush();// 强行将缓冲区的数据输出
            socket.shutdownOutput();// 关闭输出流
            // 5.关闭对应的资源
            printWriter.close();
            outputStream.close();
            bufferedReader.close();
            inputStream.close();
            inputStreamReader.close();
            socket.close();
            serverSocket.close();

        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

package com.socket;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.net.Socket;

public class Client {
    public static void main(String[] args) {
        try {
            // 1.创建客户端Socket，制定服务器地址和端口
            Socket socket = new Socket("localhost", 8888);
            // 2.获取输出流，向服务端发送信息
            OutputStream outputStream = socket.getOutputStream();// 字节输出流
            PrintWriter printWriter = new PrintWriter(outputStream);// 将输出流包装成打印流
            printWriter.print("服务端你好，我是zz");// 内容
            printWriter.flush();// 强制将缓冲区的数据输出
            socket.shutdownOutput();// 关闭输出流
            // 3.获取输入流，并读取服务器端的响应信息
            InputStream inputStream = socket.getInputStream();// 获取一个输入流，接收服务端的信息
            InputStreamReader inputStreamReader = new InputStreamReader(inputStream);// 包装成字符流，提高效率
            BufferedReader bufferedReader = new BufferedReader(inputStreamReader);// 缓冲区
            String info = "";
            String temp = null;// 临时变量
            while ((temp = bufferedReader.readLine()) != null) {
                info += temp;
                System.out.println("客户端发送的消息为：" + info);
            }
            // 4.关闭相对应的资源
            bufferedReader.close();
            inputStream.close();
            printWriter.close();
            outputStream.close();
            socket.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

 输出的结果为：

客户端发送的消息为：你好服务端已收到您的信息

服务器已启动，等待客户端连接...
已收到客户端连接
服务端接收到客户端信息：服务端你好，我是zz当前客户端ip:127.0.0.1

二、多个客户端与服务器连接：

package com.threadsocket;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.net.Socket;

public class SocketThread extends Thread{
    private Socket socket;
    public SocketThread(Socket socket) {
        this.socket = socket;
    }
    public void run() {
        //根据输入输出流和客户端连接
        try {
            InputStream inputStream = socket.getInputStream();
            //得到一个输入流，接收客户端传递的信息
            InputStreamReader inputStreamReader = new InputStreamReader(inputStream);//提高效率将字节流转化为字符流
            BufferedReader bufferedReader = new BufferedReader(inputStreamReader);//加入缓冲区
            String temp = null;
            String info = "";
            while((temp = bufferedReader.readLine())!=null) {
                info+=temp;
                System.out.println("已接收到客户端连接");
                System.out.println("服务端接收到客户端信息："+info+"当前客户端ip为："+socket.getInetAddress().getHostAddress());
            }
            OutputStream outputStream = socket.getOutputStream();//获得一个输出流向服务端发送信息
            PrintWriter printWriter = new PrintWriter(outputStream);//将输出流包装成打印流
            printWriter.flush();
            socket.shutdownOutput();//关闭输出流
            //关闭相对应的资源
            bufferedReader.close();
            inputStream.close();
            printWriter.close();
            outputStream.close();
            
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

package com.threadsocket;

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

public class Server {
    public static void main(String[] args) {
        try {
            ServerSocket serverSocket = new ServerSocket(8888);
            System.out.println("服务端已启动，等待客户端连接...");
            while(true) {
                Socket socket = serverSocket.accept();//侦听并接收到此套接字的连接返回一个Socket对象
                SocketThread socketThread = new SocketThread(socket);
                socketThread.start();
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

package com.threadsocket;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.net.Socket;
import java.net.UnknownHostException;

public class Client {
    public static void main(String[] args) {
        try {
            // 创建Socekt对象
            Socket socket = new Socket("localhost", 8888);
            // 根据输入输出流和服务端连接
            OutputStream outputStream = socket.getOutputStream();// 获取一个输出流向服务端发送信息
            PrintWriter printWriter = new PrintWriter(outputStream);
            printWriter.print("服务端你好，我是客户1");
            printWriter.flush();
            socket.shutdownOutput();// 关闭输出流

            InputStream inputStream = socket.getInputStream();// 获取一个输入流，接收服务端的信息
            InputStreamReader inputStreamReader = new InputStreamReader(inputStream);// 包装成字符流，提高效率
            BufferedReader bufferedReader = new BufferedReader(inputStreamReader);// 缓冲区
            String info = "";
            String temp = null;// 临时变量
            while ((temp = bufferedReader.readLine()) != null) {
                info += temp;
                System.out.println("客户端接收服务端发送信息：" + info);
            }
            // 关闭相对应的资源
            bufferedReader.close();
            inputStream.close();
            printWriter.close();
            outputStream.close();
            socket.close();
        } catch (UnknownHostException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

package com.threadsocket;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.net.Socket;
import java.net.UnknownHostException;

public class Client2 {
    public static void main(String[] args) {
        try {
            // 创建Socekt对象
            Socket socket = new Socket("localhost", 8888);
            // 根据输入输出流和服务端连接
            OutputStream outputStream = socket.getOutputStream();// 获取一个输出流向服务端发送信息
            PrintWriter printWriter = new PrintWriter(outputStream);
            printWriter.print("服务端你好，我是客户2");
            printWriter.flush();
            socket.shutdownOutput();// 关闭输出流

            InputStream inputStream = socket.getInputStream();// 获取一个输入流，接收服务端的信息
            InputStreamReader inputStreamReader = new InputStreamReader(inputStream);// 包装成字符流，提高效率
            BufferedReader bufferedReader = new BufferedReader(inputStreamReader);// 缓冲区
            String info = "";
            String temp = null;// 临时变量
            while ((temp = bufferedReader.readLine()) != null) {
                info += temp;
                System.out.println("客户端接收服务端发送信息：" + info);
            }
            // 关闭相对应的资源
            bufferedReader.close();
            inputStream.close();
            printWriter.close();
            outputStream.close();
            socket.close();
        } catch (UnknownHostException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

运行结果：

服务端已启动，等待客户端连接...
已接收到客户端连接
服务端接收到客户端信息：服务端你好，我是客户2当前客户端ip为：127.0.0.1
已接收到客户端连接
服务端接收到客户端信息：服务端你好，我是客户1当前客户端ip为：127.0.0.1