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怀化网站开发,wordpress博客页面无法显示,建筑行业征信查询平台,铜陵网站建设推广文章目录 TCP三次握手/TCP三次挥手TCP三次握手TCP四次挥手完整报文 实例代码HttpSampleClientHttpSampleServerHttpsSampleClientHttpsSampleServerTcpSampleClientTcpSampleServerUdpSampleClientUdpSampleSever 资料 TCP三次握手/TCP三次挥手 “三次握手”的目的是“为了防止… 文章目录 TCP三次握手/TCP三次挥手TCP三次握手TCP四次挥手完整报文 实例代码HttpSampleClientHttpSampleServerHttpsSampleClientHttpsSampleServerTcpSampleClientTcpSampleServerUdpSampleClientUdpSampleSever 资料 TCP三次握手/TCP三次挥手 “三次握手”的目的是“为了防止已失效的连接请求报文段突然又传送到了服务端因而产生 错误”。主要目的防止 server 端一直等待浪费资源。换句话说即是为了保证服务端能收 接受到客户端的信息并能做出正确的应答而进行前两次(第一次和第二次)握手为了保证客 户端能够接收到服务端的信息并能做出正确的应答而进行后两次(第二次和第三次)握手。 “四次挥手”原因是因为 tcp 是全双工模式接收到 FIN 时意味将没有数据再发来但是还是 可以继续发送数据。
TCP三次握手 TCP四次挥手 完整报文

三次握手:SYN1 Seq0

No. Time Source Destination Protocol Length Info50 7.055660280 127.0.0.1 127.0.0.1 TCP 74 44156 → 12345 [SYN] Seq0 Win65495 Len0 MSS65495 SACK_PERM TSval2731439096 TSecr0 WS128Frame 50: 74 bytes on wire (592 bits), 74 bytes captured (592 bits) on interface lo, id 0Section number: 1Interface id: 0 (lo)Encapsulation type: Ethernet (1)Arrival Time: Aug 29, 2023 08:26:32.312489778 EDT[Time shift for this packet: 0.000000000 seconds]Epoch Time: 1693311992.312489778 seconds[Time delta from previous captured frame: 0.004110298 seconds][Time delta from previous displayed frame: 0.000000000 seconds][Time since reference or first frame: 7.055660280 seconds]Frame Number: 50Frame Length: 74 bytes (592 bits)Capture Length: 74 bytes (592 bits)[Frame is marked: False][Frame is ignored: False][Protocols in frame: eth:ethertype:ip:tcp][Coloring Rule Name: TCP SYN/FIN][Coloring Rule String: tcp.flags 0x02 || tcp.flags.fin 1] Ethernet II, Src: 00:00:00_00:00:00 (00:00:00:00:00:00), Dst: 00:00:00_00:00:00 (00:00:00:00:00:00) Internet Protocol Version 4, Src: 127.0.0.1, Dst: 127.0.0.1 Transmission Control Protocol, Src Port: 44156, Dst Port: 12345, Seq: 0, Len: 0# 三次握手:SYN1 ACK1 Seq0 No. Time Source Destination Protocol Length Info51 7.055692471 127.0.0.1 127.0.0.1 TCP 74 12345 → 44156 [SYN, ACK] Seq0 Ack1 Win65483 Len0 MSS65495 SACK_PERM TSval2731439096 TSecr2731439096 WS128Frame 51: 74 bytes on wire (592 bits), 74 bytes captured (592 bits) on interface lo, id 0Section number: 1Interface id: 0 (lo)Encapsulation type: Ethernet (1)Arrival Time: Aug 29, 2023 08:26:32.312521969 EDT[Time shift for this packet: 0.000000000 seconds]Epoch Time: 1693311992.312521969 seconds[Time delta from previous captured frame: 0.000032191 seconds][Time delta from previous displayed frame: 0.000032191 seconds][Time since reference or first frame: 7.055692471 seconds]Frame Number: 51Frame Length: 74 bytes (592 bits)Capture Length: 74 bytes (592 bits)[Frame is marked: False][Frame is ignored: False][Protocols in frame: eth:ethertype:ip:tcp][Coloring Rule Name: TCP SYN/FIN][Coloring Rule String: tcp.flags 0x02 || tcp.flags.fin 1] Ethernet II, Src: 00:00:00_00:00:00 (00:00:00:00:00:00), Dst: 00:00:00_00:00:00 (00:00:00:00:00:00) Internet Protocol Version 4, Src: 127.0.0.1, Dst: 127.0.0.1 Transmission Control Protocol, Src Port: 12345, Dst Port: 44156, Seq: 0, Ack: 1, Len: 0# 三次握手:Ack1 Seq1 No. Time Source Destination Protocol Length Info52 7.055725041 127.0.0.1 127.0.0.1 TCP 66 44156 → 12345 [ACK] Seq1 Ack1 Win65536 Len0 TSval2731439096 TSecr2731439096Frame 52: 66 bytes on wire (528 bits), 66 bytes captured (528 bits) on interface lo, id 0Section number: 1Interface id: 0 (lo)Encapsulation type: Ethernet (1)Arrival Time: Aug 29, 2023 08:26:32.312554539 EDT[Time shift for this packet: 0.000000000 seconds]Epoch Time: 1693311992.312554539 seconds[Time delta from previous captured frame: 0.000032570 seconds][Time delta from previous displayed frame: 0.000032570 seconds][Time since reference or first frame: 7.055725041 seconds]Frame Number: 52Frame Length: 66 bytes (528 bits)Capture Length: 66 bytes (528 bits)[Frame is marked: False][Frame is ignored: False][Protocols in frame: eth:ethertype:ip:tcp][Coloring Rule Name: TCP][Coloring Rule String: tcp] Ethernet II, Src: 00:00:00_00:00:00 (00:00:00:00:00:00), Dst: 00:00:00_00:00:00 (00:00:00:00:00:00) Internet Protocol Version 4, Src: 127.0.0.1, Dst: 127.0.0.1 Transmission Control Protocol, Src Port: 44156, Dst Port: 12345, Seq: 1, Ack: 1, Len: 0# 客户端发送消息 Hello, server!. No. Time Source Destination Protocol Length Info53 7.057834891 127.0.0.1 127.0.0.1 TCP 81 44156 → 12345 [PSH, ACK] Seq1 Ack1 Win65536 Len15 TSval2731439098 TSecr2731439096Frame 53: 81 bytes on wire (648 bits), 81 bytes captured (648 bits) on interface lo, id 0Section number: 1Interface id: 0 (lo)Encapsulation type: Ethernet (1)Arrival Time: Aug 29, 2023 08:26:32.314664389 EDT[Time shift for this packet: 0.000000000 seconds]Epoch Time: 1693311992.314664389 seconds[Time delta from previous captured frame: 0.002109850 seconds][Time delta from previous displayed frame: 0.002109850 seconds][Time since reference or first frame: 7.057834891 seconds]Frame Number: 53Frame Length: 81 bytes (648 bits)Capture Length: 81 bytes (648 bits)[Frame is marked: False][Frame is ignored: False][Protocols in frame: eth:ethertype:ip:tcp:data][Coloring Rule Name: TCP][Coloring Rule String: tcp] Ethernet II, Src: 00:00:00_00:00:00 (00:00:00:00:00:00), Dst: 00:00:00_00:00:00 (00:00:00:00:00:00) Internet Protocol Version 4, Src: 127.0.0.1, Dst: 127.0.0.1 Transmission Control Protocol, Src Port: 44156, Dst Port: 12345, Seq: 1, Ack: 1, Len: 15 Data (15 bytes)0000 48 65 6c 6c 6f 2c 20 73 65 72 76 65 72 21 0a Hello, server!.# 服务端应答 No. Time Source Destination Protocol Length Info54 7.057859991 127.0.0.1 127.0.0.1 TCP 66 12345 → 44156 [ACK] Seq1 Ack16 Win65536 Len0 TSval2731439098 TSecr2731439098Frame 54: 66 bytes on wire (528 bits), 66 bytes captured (528 bits) on interface lo, id 0Section number: 1Interface id: 0 (lo)Encapsulation type: Ethernet (1)Arrival Time: Aug 29, 2023 08:26:32.314689489 EDT[Time shift for this packet: 0.000000000 seconds]Epoch Time: 1693311992.314689489 seconds[Time delta from previous captured frame: 0.000025100 seconds][Time delta from previous displayed frame: 0.000025100 seconds][Time since reference or first frame: 7.057859991 seconds]Frame Number: 54Frame Length: 66 bytes (528 bits)Capture Length: 66 bytes (528 bits)[Frame is marked: False][Frame is ignored: False][Protocols in frame: eth:ethertype:ip:tcp][Coloring Rule Name: TCP][Coloring Rule String: tcp] Ethernet II, Src: 00:00:00_00:00:00 (00:00:00:00:00:00), Dst: 00:00:00_00:00:00 (00:00:00:00:00:00) Internet Protocol Version 4, Src: 127.0.0.1, Dst: 127.0.0.1 Transmission Control Protocol, Src Port: 12345, Dst Port: 44156, Seq: 1, Ack: 16, Len: 0# 服务端发送消息 Server received: Hello, server!. No. Time Source Destination Protocol Length Info55 7.059237157 127.0.0.1 127.0.0.1 TCP 98 12345 → 44156 [PSH, ACK] Seq1 Ack16 Win65536 Len32 TSval2731439100 TSecr2731439098Frame 55: 98 bytes on wire (784 bits), 98 bytes captured (784 bits) on interface lo, id 0Section number: 1Interface id: 0 (lo)Encapsulation type: Ethernet (1)Arrival Time: Aug 29, 2023 08:26:32.316066655 EDT[Time shift for this packet: 0.000000000 seconds]Epoch Time: 1693311992.316066655 seconds[Time delta from previous captured frame: 0.001377166 seconds][Time delta from previous displayed frame: 0.001377166 seconds][Time since reference or first frame: 7.059237157 seconds]Frame Number: 55Frame Length: 98 bytes (784 bits)Capture Length: 98 bytes (784 bits)[Frame is marked: False][Frame is ignored: False][Protocols in frame: eth:ethertype:ip:tcp:data][Coloring Rule Name: TCP][Coloring Rule String: tcp] Ethernet II, Src: 00:00:00_00:00:00 (00:00:00:00:00:00), Dst: 00:00:00_00:00:00 (00:00:00:00:00:00) Internet Protocol Version 4, Src: 127.0.0.1, Dst: 127.0.0.1 Transmission Control Protocol, Src Port: 12345, Dst Port: 44156, Seq: 1, Ack: 16, Len: 32 Data (32 bytes)0000 53 65 72 76 65 72 20 72 65 63 65 69 76 65 64 3a Server received: 0010 20 48 65 6c 6c 6f 2c 20 73 65 72 76 65 72 21 0a Hello, server!.# 客户端还给了一个回应 No. Time Source Destination Protocol Length Info56 7.059273656 127.0.0.1 127.0.0.1 TCP 66 44156 → 12345 [ACK] Seq16 Ack33 Win65536 Len0 TSval2731439100 TSecr2731439100Frame 56: 66 bytes on wire (528 bits), 66 bytes captured (528 bits) on interface lo, id 0Section number: 1Interface id: 0 (lo)Encapsulation type: Ethernet (1)Arrival Time: Aug 29, 2023 08:26:32.316103154 EDT[Time shift for this packet: 0.000000000 seconds]Epoch Time: 1693311992.316103154 seconds[Time delta from previous captured frame: 0.000036499 seconds][Time delta from previous displayed frame: 0.000036499 seconds][Time since reference or first frame: 7.059273656 seconds]Frame Number: 56Frame Length: 66 bytes (528 bits)Capture Length: 66 bytes (528 bits)[Frame is marked: False][Frame is ignored: False][Protocols in frame: eth:ethertype:ip:tcp][Coloring Rule Name: TCP][Coloring Rule String: tcp] Ethernet II, Src: 00:00:00_00:00:00 (00:00:00:00:00:00), Dst: 00:00:00_00:00:00 (00:00:00:00:00:00) Internet Protocol Version 4, Src: 127.0.0.1, Dst: 127.0.0.1 Transmission Control Protocol, Src Port: 44156, Dst Port: 12345, Seq: 16, Ack: 33, Len: 0# 四次挥手 1 FIN1 Ack33 Seq16 No. Time Source Destination Protocol Length Info57 7.062253079 127.0.0.1 127.0.0.1 TCP 66 44156 → 12345 [FIN, ACK] Seq16 Ack33 Win65536 Len0 TSval2731439103 TSecr2731439100Frame 57: 66 bytes on wire (528 bits), 66 bytes captured (528 bits) on interface lo, id 0Section number: 1Interface id: 0 (lo)Encapsulation type: Ethernet (1)Arrival Time: Aug 29, 2023 08:26:32.319082577 EDT[Time shift for this packet: 0.000000000 seconds]Epoch Time: 1693311992.319082577 seconds[Time delta from previous captured frame: 0.002979423 seconds][Time delta from previous displayed frame: 0.002979423 seconds][Time since reference or first frame: 7.062253079 seconds]Frame Number: 57Frame Length: 66 bytes (528 bits)Capture Length: 66 bytes (528 bits)[Frame is marked: False][Frame is ignored: False][Protocols in frame: eth:ethertype:ip:tcp][Coloring Rule Name: TCP SYN/FIN][Coloring Rule String: tcp.flags 0x02 || tcp.flags.fin 1] Ethernet II, Src: 00:00:00_00:00:00 (00:00:00:00:00:00), Dst: 00:00:00_00:00:00 (00:00:00:00:00:00) Internet Protocol Version 4, Src: 127.0.0.1, Dst: 127.0.0.1 Transmission Control Protocol, Src Port: 44156, Dst Port: 12345, Seq: 16, Ack: 33, Len: 0# 四次挥手 2 ACK17 Seq33 No. Time Source Destination Protocol Length Info58 7.110165407 127.0.0.1 127.0.0.1 TCP 66 12345 → 44156 [ACK] Seq33 Ack17 Win65536 Len0 TSval2731439151 TSecr2731439103Frame 58: 66 bytes on wire (528 bits), 66 bytes captured (528 bits) on interface lo, id 0Section number: 1Interface id: 0 (lo)Encapsulation type: Ethernet (1)Arrival Time: Aug 29, 2023 08:26:32.366994905 EDT[Time shift for this packet: 0.000000000 seconds]Epoch Time: 1693311992.366994905 seconds[Time delta from previous captured frame: 0.047912328 seconds][Time delta from previous displayed frame: 0.047912328 seconds][Time since reference or first frame: 7.110165407 seconds]Frame Number: 58Frame Length: 66 bytes (528 bits)Capture Length: 66 bytes (528 bits)[Frame is marked: False][Frame is ignored: False][Protocols in frame: eth:ethertype:ip:tcp][Coloring Rule Name: TCP][Coloring Rule String: tcp] Ethernet II, Src: 00:00:00_00:00:00 (00:00:00:00:00:00), Dst: 00:00:00_00:00:00 (00:00:00:00:00:00) Internet Protocol Version 4, Src: 127.0.0.1, Dst: 127.0.0.1 Transmission Control Protocol, Src Port: 12345, Dst Port: 44156, Seq: 33, Ack: 17, Len: 0# 四次挥手: 3 Fin1 Ack17 Seq33 No. Time Source Destination Protocol Length Info61 7.390471256 127.0.0.1 127.0.0.1 TCP 66 12345 → 44156 [FIN, ACK] Seq33 Ack17 Win65536 Len0 TSval2731439431 TSecr2731439103Frame 61: 66 bytes on wire (528 bits), 66 bytes captured (528 bits) on interface lo, id 0Section number: 1Interface id: 0 (lo)Encapsulation type: Ethernet (1)Arrival Time: Aug 29, 2023 08:26:32.647300754 EDT[Time shift for this packet: 0.000000000 seconds]Epoch Time: 1693311992.647300754 seconds[Time delta from previous captured frame: 0.000234452 seconds][Time delta from previous displayed frame: 0.280305849 seconds][Time since reference or first frame: 7.390471256 seconds]Frame Number: 61Frame Length: 66 bytes (528 bits)Capture Length: 66 bytes (528 bits)[Frame is marked: False][Frame is ignored: False][Protocols in frame: eth:ethertype:ip:tcp][Coloring Rule Name: TCP SYN/FIN][Coloring Rule String: tcp.flags 0x02 || tcp.flags.fin 1] Ethernet II, Src: 00:00:00_00:00:00 (00:00:00:00:00:00), Dst: 00:00:00_00:00:00 (00:00:00:00:00:00) Internet Protocol Version 4, Src: 127.0.0.1, Dst: 127.0.0.1 Transmission Control Protocol, Src Port: 12345, Dst Port: 44156, Seq: 33, Ack: 17, Len: 0# 四次挥手 4 Ack34 Seq17 No. Time Source Destination Protocol Length Info62 7.390499061 127.0.0.1 127.0.0.1 TCP 66 44156 → 12345 [ACK] Seq17 Ack34 Win65536 Len0 TSval2731439431 TSecr2731439431Frame 62: 66 bytes on wire (528 bits), 66 bytes captured (528 bits) on interface lo, id 0Section number: 1Interface id: 0 (lo)Encapsulation type: Ethernet (1)Arrival Time: Aug 29, 2023 08:26:32.647328559 EDT[Time shift for this packet: 0.000000000 seconds]Epoch Time: 1693311992.647328559 seconds[Time delta from previous captured frame: 0.000027805 seconds][Time delta from previous displayed frame: 0.000027805 seconds][Time since reference or first frame: 7.390499061 seconds]Frame Number: 62Frame Length: 66 bytes (528 bits)Capture Length: 66 bytes (528 bits)[Frame is marked: False][Frame is ignored: False][Protocols in frame: eth:ethertype:ip:tcp][Coloring Rule Name: TCP][Coloring Rule String: tcp] Ethernet II, Src: 00:00:00_00:00:00 (00:00:00:00:00:00), Dst: 00:00:00_00:00:00 (00:00:00:00:00:00) Internet Protocol Version 4, Src: 127.0.0.1, Dst: 127.0.0.1 Transmission Control Protocol, Src Port: 44156, Dst Port: 12345, Seq: 17, Ack: 34, Len: 0 实例代码 HttpSampleClient import java.io.BufferedReader; import java.io.InputStreamReader; import java.net.HttpURLConnection; import java.net.URL;public class HttpSampleClient {public static void main(String[] args) {try {URL url new URL(http://localhost:8080);HttpURLConnection connection (HttpURLConnection) url.openConnection();connection.setRequestMethod(GET);int responseCode connection.getResponseCode();System.out.println(Response Code: responseCode);// read contentBufferedReader reader new BufferedReader(new InputStreamReader(connection.getInputStream()));String line;StringBuilder response new StringBuilder();while ((line reader.readLine()) ! null) {response.append(line);}reader.close();System.out.println(Response Body: response);connection.disconnect();} catch (Exception e) {e.printStackTrace();}} } HttpSampleServer import com.sun.net.httpserver.HttpExchange; import com.sun.net.httpserver.HttpHandler; import com.sun.net.httpserver.HttpServer;import java.io.IOException; import java.io.OutputStream; import java.net.InetSocketAddress;public class HttpSampleServer {public static void main(String[] args) {try {// create http server to bind 8080HttpServer server HttpServer.create(new InetSocketAddress(127.0.0.1, 8080), 0);// bind pathserver.createContext(/, new MyHandler());server.start();System.out.println(Http Sever started on port 8080);} catch (Exception e) {e.printStackTrace();}}static class MyHandler implements HttpHandler {// 设置响应头cOverridepublic void handle(HttpExchange exchange) throws IOException {String response Hello from the local HTTP server!;exchange.sendResponseHeaders(200, response.getBytes().length);// 获取输出流并写入响应内容OutputStream os exchange.getResponseBody();os.write(response.getBytes());os.close();}} } HttpsSampleClient import javax.net.ssl.; import java.io.BufferedReader; import java.io.InputStreamReader; import java.io.PrintWriter;public class HttpsSampleClient {public static void main(String[] args) {try {// Create and configure the SSL contextSSLContext sslContext SSLContext.getInstance(TLS);sslContext.init(null, new TrustManager[]{new X509TrustManager() {public java.security.cert.X509Certificate[] getAcceptedIssuers() {return null;}public void checkClientTrusted(java.security.cert.X509Certificate[] certs, String authType) {}public void checkServerTrusted(java.security.cert.X509Certificate[] certs, String authType) {}}}, new java.security.SecureRandom());// Create an SSL socketSSLSocketFactory sslSocketFactory sslContext.getSocketFactory();SSLSocket socket (SSLSocket) sslSocketFactory.createSocket(localhost, 12345);// Get input and output streams for secure communicationBufferedReader reader new BufferedReader(new InputStreamReader(socket.getInputStream()));PrintWriter writer new PrintWriter(socket.getOutputStream(), true); // autoFlush// Send a message to the serverString message Hello, server!;writer.println(message);// Read response from the serverString serverResponse reader.readLine();System.out.println(Server response: serverResponse);// Close resourcesreader.close();writer.close();socket.close();} catch (Exception e) {e.printStackTrace();}} } HttpsSampleServer import javax.net.ssl.; import java.io.BufferedReader; import java.io.FileInputStream; import java.io.InputStreamReader; import java.io.PrintWriter; import java.security.KeyStore;public class HttpsSampleServer {public static void main(String[] args) {String keystorePath ./keystore.jks;char[] keystorePassword flannery.toCharArray();try {// Load the keystore containing the servers SSL certificateKeyStore keystore KeyStore.getInstance(JKS);keystore.load(new FileInputStream(keystorePath), keystorePassword);// Create and configure the SSL contextKeyManagerFactory kmf KeyManagerFactory.getInstance(SunX509);kmf.init(keystore, keystorePassword);SSLContext sslContext SSLContext.getInstance(TLS);sslContext.init(kmf.getKeyManagers(), null, null);// Create an SSL server socketSSLServerSocketFactory sslServerSocketFactory sslContext.getServerSocketFactory();SSLServerSocket serverSocket (SSLServerSocket) sslServerSocketFactory.createServerSocket(12345);System.out.println(Server listening on port 12345…);// Wait for a client to connectSSLSocket clientSocket (SSLSocket) serverSocket.accept();System.out.println(Client connected: clientSocket.getInetAddress().getHostAddress());// Get input and output streams for secure communicationBufferedReader reader new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));PrintWriter writer new PrintWriter(clientSocket.getOutputStream(), true); // autoFlush// Read data from client and respondString clientMessage;while ((clientMessage reader.readLine()) ! null) {System.out.println(Received from client: clientMessage);writer.println(Server received: clientMessage);}// Close resourcesreader.close();writer.close();clientSocket.close();serverSocket.close();} catch (Exception e) {e.printStackTrace();}} } TcpSampleClient import java.io.; import java.net.Socket;public class TcpSampleClient {public static void main(String[] args) {try {// Create a socket to connect to the serverSocket socket new Socket(localhost, 12345);// Get input and output streams for the socketInputStream inputStream socket.getInputStream();OutputStream outputStream socket.getOutputStream();// Create readers and writers for easier communicationBufferedReader reader new BufferedReader(new InputStreamReader(inputStream));PrintWriter writer new PrintWriter(outputStream, true); // autoFlush// Send a message to the serverString message Hello, server!;writer.println(message);// Read response from the serverString serverResponse reader.readLine();System.out.println(Server response: serverResponse);// Close resourcesreader.close();writer.close();socket.close();} catch (IOException e) {e.printStackTrace();}} } TcpSampleServer import java.io.; import java.net.ServerSocket; import java.net.Socket; public class TcpSampleServer {public static void main(String[] args) {extracted();}private static void extracted() {try {// Create a server socketServerSocket serverSocket new ServerSocket(12345);System.out.println(Server listening on port 12345…);// Wait for a client to connectSocket clientSocket serverSocket.accept();System.out.println(Client connected: clientSocket.getInetAddress().getHostAddress());// Get input and output streams for the socketInputStream inputStream clientSocket.getInputStream();OutputStream outputStream clientSocket.getOutputStream();// Create readers and writers for easier communicationBufferedReader reader new BufferedReader(new InputStreamReader(inputStream));PrintWriter writer new PrintWriter(outputStream, true); // autoFlush// Read data from client and respondString clientMessage;while ((clientMessage reader.readLine()) ! null) {System.out.println(Received from client: clientMessage);writer.println(Server received: clientMessage);}// Close resources//reader.close();//writer.close();//clientSocket.close();//serverSocket.close();} catch (IOException e) {e.printStackTrace();}}} UdpSampleClient import java.io.IOException; import java.net.DatagramPacket; import java.net.DatagramSocket; import java.net.InetAddress;public class UdpSampleClient {public static void main(String[] args) {try {DatagramSocket clientSocket new DatagramSocket();String message Hello, server!;byte[] sendData message.getBytes();InetAddress serverAddress InetAddress.getByName(localhost);int serverPort 12345;DatagramPacket sendPacket new DatagramPacket(sendData, sendData.length, serverAddress, serverPort);clientSocket.send(sendPacket);byte[] receiveData new byte[1024];DatagramPacket receivePacket new DatagramPacket(receiveData, receiveData.length);clientSocket.receive(receivePacket);String serverResponse new String(receivePacket.getData(), 0, receivePacket.getLength());System.out.println(Server response: serverResponse);clientSocket.close();} catch (IOException e) {e.printStackTrace();}}} UdpSampleSever import java.io.IOException; import java.net.DatagramPacket; import java.net.DatagramSocket; import java.net.InetAddress;public class UdpSampleSever {public static void main(String[] args) {try {DatagramSocket serverSocket new DatagramSocket(12345);System.out.println(Server listening on port 12345…);byte[] receiveData new byte[1024];while (true) {DatagramPacket receivePacket new DatagramPacket(receiveData, receiveData.length);serverSocket.receive(receivePacket);String clientMessage new String(receivePacket.getData(), 0, receivePacket.getLength());System.out.println(Received from client: clientMessage);InetAddress clientAddress receivePacket.getAddress();int clientPort receivePacket.getPort();String serverResponse Server received: clientMessage;byte[] sendData serverResponse.getBytes();DatagramPacket sendPacket new DatagramPacket(sendData, sendData.length, clientAddress, clientPort);serverSocket.send(sendPacket);}} catch (IOException e) {e.printStackTrace();}} } 资料 超详细的wireshark抓包使用教程 jks证书文件的生成步骤 如何使用wireshark抓取HTTPS数据包 wireshark抓包分析HTTPS Burp Suite的基本介绍及使用 渗透测试工具Burp Suite详解 vmware ctrl键粘滞的问题 wireshark过滤规则 Burp Suite HTTPS详解