TCP:传输控制协议
-
特点:面向连接、可靠通信
-
TCP的最终目的:要保证在不可靠的信道上实现可靠的传输
-
TCP主要有三个步骤实现可靠传输:三次握手建立连接,传输数据进行确认,四次挥手断开连接
-
三次握手建立可靠连接。
-
建立连接后会建立可靠的通信管道
-
四次握手断开连接
-
TCP通信之客户端开发
客户端发送信息:
import java.io.*;
import java.net.*;
public class TCPClient {
public static void main(String[] args) {
final String serverAddress = "127.0.0.1"; // 服务器地址
final int serverPort = 8080; // 服务器端口
try {
// 连接到服务器
Socket socket = new Socket(serverAddress, serverPort);
System.out.println("Connected to server.");
// 发送消息到服务器
sendMessage(socket, "Hello, Server!");
// 接收服务器的响应
String response = receiveMessage(socket);
System.out.println("Response from server: " + response);
// 关闭连接
socket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
private static void sendMessage(Socket socket, String message) throws IOException {
PrintWriter out = new PrintWriter(socket.getOutputStream(), true);
out.println(message);
}
private static String receiveMessage(Socket socket) throws IOException {
BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
return in.readLine();
}
}
TCP通信之服务端开发
服务端接收信息
import java.io.*;
import java.net.*;
public class TCPExample {
public static void main(String[] args) {
final int PORT = 8080;
try {
// 启动服务器
ServerSocket serverSocket = new ServerSocket(PORT);
System.out.println("Server started. Waiting for connections...");
// 等待客户端连接
Socket clientSocket = serverSocket.accept();
System.out.println("Client connected: " + clientSocket);
// 处理客户端请求
handleClient(clientSocket);
// 关闭服务器
serverSocket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
public static void handleClient(Socket clientSocket) {
try {
// 接收客户端消息
BufferedReader in = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));
String message = in.readLine();
System.out.println("Received message from client: " + message);
// 向客户端发送响应
PrintWriter out = new PrintWriter(clientSocket.getOutputStream(), true);
out.println("Hello, Client!");
// 关闭连接
clientSocket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}