add net

README.md

-# Java Demo
+# 参考原文
 
-配套文章
 [【七日阅书】1 计算思维和Java特性《Java程序设计与计算思维》](https://blog.csdn.net/diandianxiyu_geek/article/details/121660902?spm=1001.2014.3001.5501)
 
 [【七日阅书】2 Java的数据类型和流程控制《Java程序设计与计算思维》](https://blog.csdn.net/diandianxiyu_geek/article/details/121681529?spm=1001.2014.3001.5501)
 
 [【七日阅书】3 字符串、数组、集合、泛型《Java程序设计与计算思维》](https://blog.csdn.net/diandianxiyu_geek/article/details/121703793?spm=1001.2014.3001.5501)
 
+[【七日阅书】4 理解面向对象《Java程序设计与计算思维》](https://blog.csdn.net/diandianxiyu_geek/article/details/121723434?spm=1001.2014.3001.5501)
 
+[【七日阅书】5 抽象和接口、异常处理《Java程序设计与计算思维》](https://blog.csdn.net/diandianxiyu_geek/article/details/121767341?spm=1001.2014.3001.5501)
 
+[【七日阅书】6 多线程和文件流《Java程序设计与计算思维》](https://blog.csdn.net/diandianxiyu_geek/article/details/121797455?spm=1001.2014.3001.5501)
+
+[【七日阅书】7 网络通信&全书总评《Java程序设计与计算思维》](https://coderfix.blog.csdn.net/article/details/121819159)
 
 
 

src/main/java/com/example/demo/controller/NetController.java

+package com.example.demo.controller;
+
+import com.example.demo.tool.Server;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+import java.io.*;
+import java.net.*;
+
+@RestController
+@RequestMapping("/")
+public class NetController {
+
+    @GetMapping("/net-base")
+    public void baseDemo() throws UnknownHostException {
+        InetAddress inetAddress = InetAddress.getLocalHost();
+        System.out.print(inetAddress.getHostAddress());
+        System.out.print("\r\n");
+        System.out.print(inetAddress.getHostName());
+    }
+
+    @GetMapping("/socket")
+    public void socketDemo(){
+        Server server;
+        int port = 1024;
+        BufferedReader bufferedReader;
+        PrintWriter printWriter;
+        server = new Server(port);
+        bufferedReader = new BufferedReader(new InputStreamReader(server.inputStream));
+        printWriter = new PrintWriter(new OutputStreamWriter(server.outputStream));
+    }
+
+    @GetMapping("/udp-r")
+    public void udpDemo() throws IOException {
+        DatagramPacket datagramPacket;
+        DatagramSocket datagramSocket;
+        byte[] buffer = new byte[20];
+        String msg;
+        System.out.print("服务端开始接收数据");
+        while (true){
+            datagramPacket = new DatagramPacket(buffer, buffer.length);
+            datagramSocket = new DatagramSocket(9995);
+            datagramSocket.receive(datagramPacket);
+            msg = new String(buffer,0,datagramPacket.getLength());
+            System.out.print("信息为：" + msg + "\r\n");
+            datagramSocket.close();
+        }
+    }
+
+    @GetMapping("/udp-s")
+    public void udpSendDemo() throws IOException {
+        System.out.print("发送消息\r\n");
+        String msg= "msg 123232";
+        byte[]  buffer = msg.getBytes();
+        DatagramPacket datagramPacket = new DatagramPacket(buffer,buffer.length, InetAddress.getByName("127.0.0.1"),9995);
+        DatagramSocket datagramSocket = new DatagramSocket();
+        datagramSocket.send(datagramPacket);
+        datagramSocket.close();
+    }
+
+    @GetMapping("/url")
+    public void urlDemo() throws MalformedURLException {
+        URL url = new URL("https://blog.csdn.net/diandianxiyu_geek");
+        System.out.print(url.getProtocol() + "\r\n");
+        System.out.print(url.getPath() + "\r\n");
+        System.out.print(url.getHost() + "\r\n");
+        System.out.print(url.getFile() + "\r\n");
+        System.out.print(url.getQuery() + "\r\n");
+        System.out.print(url.getRef() + "\r\n");
+    }
+}

src/main/java/com/example/demo/tool/Server.java

+package com.example.demo.tool;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.net.ServerSocket;
+import java.net.Socket;
+import java.nio.charset.StandardCharsets;
+
+public class Server {
+    ServerSocket serverSocket;
+    Socket socket;
+    public InputStream inputStream;
+    public OutputStream outputStream;
+
+    public Server(int port){
+        try{
+            serverSocket = new ServerSocket(port);
+            while (true){
+                socket = serverSocket.accept();
+                inputStream = socket.getInputStream();
+                outputStream = socket.getOutputStream();
+                String line = System.getProperty("line.separator");
+                String out = "服务器信息：" + line + serverSocket.getInetAddress().getHostName()
+                        + line + serverSocket.getLocalPort();
+                outputStream.write(out.getBytes(StandardCharsets.UTF_8));
+            }
+
+        } catch (IOException exception) {
+            System.err.print(exception.toString());
+        }
+
+    }
+}