TCP

TCP：客户端 

package com.alibaba.interview; import java.io.PrintWriter; import java.net.Socket; /** * @author: WSC * @Create 2020/9/2 14:50 */ public class TcpClient { public static void main(String[] args) throws Exception { String msg = "7e 7e 01 00 18 01 01 00 00 00 00 00 00 00 66 f7 80 a2 73 01 00 00 ff ff 04 00 37 00 00 00 46 82 33 41 c7 4f 28 40 4e dd 53 40 fa 2c ae 43 37 47 88 3c 00 00 b4 42 00 00 80 bf 00 00 80 bf f3 d7 b6 c6 6e 92 5a 40 56 e2 7e f9 ac 85 3d 40 ff ff 04 00 35 00 00 00 46 d2 2e 41 36 ee 40 40 19 61 4e 40 35 92 ab 43 d1 45 6e 3f 82 04 1f 43 00 00 80 bf 00 00 80 bf 6e df 41 44 77 92 5a 40 dd 20 e0 ac 7c 85 3d 40 ff ff 04 00 38 00 00 00 d0 09 d0 40 6a 23 0e 40 31 1a 2f 40 6f 14 ae 43 8e d7 87 40 4c 56 32 43 00 00 80 bf 00 00 80 bf a9 fa a2 c2 72 92 5a 40 94 9d c9 d1 a3 85 3d 40 ff ff 03 00 36 00 00 00 15 fa 8f 40 b8 a8 f4 3f ad 30 e6 3f 52 28 9b 43 8d 30 83 40 fa 77 09 43 00 00 80 bf 00 00 80 bf 1e 66 63 34 7c 92 5a 40 70 65 99 cd 8a 85 3d 40 ff ff 04 00 39 00 00 00 0f 0a 05 41 de 21 2e 40 e9 5e 46 40 b4 68 9b 43 bf 48 e5 3f b3 d3 8c 43 00 00 80 bf 00 00 80 bf d6 3f 38 92 7e 92 5a 40 f5 a5 e5 91 86 85 3d 40 72 fe 7e 7d"; //创建一个Socket,跟本机的8888端口进行连接 Socket socket = new Socket("127.0.0.1", 8888); //使用Socket创建一个PrintWriter进行写数据 PrintWriter printWriter = new PrintWriter(socket.getOutputStream()); //发送数据 printWriter.println(msg); //刷新一下，使得服务立马可以收到请求信息 printWriter.flush(); //printWriter.println(msg); //关闭资源 printWriter.close(); socket.close(); } }

TCP服务端

package com.alibaba.interview; import java.io.BufferedReader; import java.io.BufferedWriter; import java.io.InputStreamReader; import java.io.OutputStreamWriter; import java.net.ServerSocket; import java.net.Socket; import java.util.Arrays; /** * @author: WSC * @Create 2020/9/2 14:49 */ public class TcpServer { public static void main(String[] args) throws Exception { //创建一个ServerSocket监听一个端：8888 ServerSocket serverSocket = new ServerSocket(8888); System.out.println("TCP服务器已经启动，端口是8888"); //无限循环 while (true) { //等待客户端的请求，如果有请求分配一个Socket Socket socket = serverSocket.accept(); //根据标准输入构造一个BufferedReader对象 BufferedReader reader = new BufferedReader(new InputStreamReader(socket.getInputStream())); String buffer = null; //循环读取输入的每一行数据 while ((buffer = reader.readLine()) != null && !buffer.equals("")) { System.out.println(Arrays.toString(buffer.split(" "))); String replace = buffer.replace(" ", ""); System.out.println(replace); System.out.println(replace.substring(0, 4)); System.out.println(replace.substring(4, 6)); System.out.println(replace.substring(6, 8)); System.out.println(replace.substring(8, 12)); System.out.println(replace.substring(12, 28)); System.out.println(replace.substring(28, 44)); String temp = replace.substring(44, replace.length() - 8); int index = 0; while ((index = temp.lastIndexOf("ffff")) != -1) { System.out.println(temp.substring(index)); System.out.println(temp.substring(index).length()); System.out.println(temp.substring(index).substring(0, 2)); System.out.println(temp.substring(index).substring(2, 4)); System.out.println(temp.substring(index).substring(4, 6)); System.out.println(temp.substring(index).substring(8, 16)); System.out.println(temp.substring(index).substring(16, 24)); System.out.println(temp.substring(index).substring(24, 32)); System.out.println(temp.substring(index).substring(32, 40)); System.out.println(temp.substring(index).substring(40, 48)); System.out.println(temp.substring(index).substring(56, 64)); System.out.println(temp.substring(index).substring(64, 72)); System.out.println(temp.substring(index).substring(72, 80)); System.out.println(temp.substring(index).substring(80, 96)); System.out.println(temp.substring(index).substring(96, 112)); temp = temp.substring(0, index); } System.out.println(replace.substring(replace.length() - 8, replace.length() - 4)); System.out.println(replace.substring(replace.length() - 4, replace.length())); } //通过Socket对象得到输出流，构造BufferedWrite对象 BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(socket.getOutputStream())); //模拟了http的请求头信息 writer.write("HTTP/1.1 200 OK \r\n Content-Type:text/html \r\n charset=UTF-8\r\n\r\n "); //写一些html的体 writer.write("<html><head><title>http请求</title></head><body><h1>这是一个HTTP请求！</h1></body></html>"); //刷新输出流，使得数据立马发送 writer.flush(); //关闭 reader.close(); writer.close(); socket.close(); } } }

UDP

UDP发送端

package com.alibaba.interview; import java.io.BufferedReader; import java.io.InputStreamReader; import java.net.DatagramPacket; import java.net.DatagramSocket; import java.net.InetAddress; /** * @author: WSC * @Create 2020/9/2 17:45 */ public class UDPSendDemo { public static void main(String[] args) throws Exception { //创建一个DatagramSocket实例 DatagramSocket datagramSocket = new DatagramSocket(); //使用键盘输入构建一个BufferedReader BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(System.in)); String line = null; while ((line = bufferedReader.readLine()) != null) { //转成byte byte[] bytes = line.getBytes(); //创建一个用于发送的DatagramPacket对象 DatagramPacket datagramPacket = new DatagramPacket(bytes, bytes.length, InetAddress.getByName("127.0.0.1"), 10005); //发送数据包 datagramSocket.send(datagramPacket); if ("88".equals(line)) {//当输入88时结束发送 break; } } System.out.println("UDP发送端已发送结束。。。。。。。。。"); //关闭 datagramSocket.close(); } }

UDP接收端

package com.alibaba.interview; import java.net.DatagramPacket; import java.net.DatagramSocket; /** * @author: WSC * @Create 2020/9/2 17:45 */ public class UDPReciveDemo { public static void main(String[] args) throws Exception { //创建一个DatagramSocket实例,并且把实例绑定到本机的地址，端口10005 DatagramSocket datagramSocket = new DatagramSocket(10005); byte bytes[] = new byte[1024]; //以一个空数组来创建 DatagramPacket,这个对象作用是接收DatagramSocket中的数据 DatagramPacket datagramPacket = new DatagramPacket(bytes, bytes.length); System.out.println("UDP接收端已启动。。。。。。。。。"); while (true) {//无限循环是必须要的，因为不知道数据何时来 //接收到的数据包 datagramSocket.receive(datagramPacket); //获取接收的数据 byte[] data = datagramPacket.getData(); //把数组转成字符 String str = new String(data, 0, datagramPacket.getLength()); //如果数据包中是88的信息，则跳出并且关闭 if ("88".equals(str)) { break; } //打印数据 System.out.println("接收到的数据为:" + str); } //关闭 datagramSocket.close(); } }

注意tcp必须先启动服务端，再启动客户端；而udp启动顺序没有先后顺序。