Java网络编程：Socket通信及TCP/UDP协议理解实例

原创素颜马尾好姑娘i 2024-10-21 02:00 38阅读 0赞

在Java中，Socket编程是进行网络通信的基础。以下我们将通过一个实例来理解Socket通信以及TCP/UDP协议。

首先，我们需要导入所需的包：
```java
import java.io.*;
import java.net.*;

// Your class here
```

然后，创建一个服务器端的Socket监听器：
```java
public class Server {
    public static void main(String[] args) throws IOException {
        // Create a server socket
        ServerSocket ss = new ServerSocket(1234); // Set the port

System.out.println("Server listening on port 1234...");

// Accept client connections
        Socket cSocket = ss.accept();

System.out.println("Connection accepted from client!");

// Handle client data
        handleClient(cSocket);
    }

// Function to handle client data
    private static void handleClient(Socket cSocket) throws IOException {
        DataOutputStream dos = new DataOutputStream(cSocket.getOutputStream()));

// Send a message to the client
        dos.writeUTF("Welcome! You are connected to the server.");

dos.flush();

// Close streams
        dos.close();
        cSocket.close();
    }
}
```

在客户端，我们可以创建一个Socket来连接到服务器：

```java
public class Client {
    public static void main(String[] args) throws IOException {
        // Create a client socket
        Socket s = new Socket("localhost", 1234)); // Replace "localhost" with your server's IP address if not running on the same machine

System.out.println("Client connected to server at port 1234...");

// Send data to server and receive response
        sendAndReceive(s, "Hello from client!");

s.close();
    }

// Function to send data to server and receive response
    private static void sendAndReceive(Socket s, String message) throws IOException {
        DataOutputStream dos = new DataOutputStream(s.getOutputStream()));

// Send the message to the server
        dos.writeUTF(message);

dos.flush();

// Receive the response from the server
        byte[] buffer = new byte[1024]; // Adjust buffer size as needed
        int length = s.getInputStream().read(buffer));

String response = new String(buffer, 0, length)); // Remove excess bytes

System.out.println("Received response: " + response);

dos.close();
    }
}
```

以上代码中，服务器监听1234端口，客户端连接到这个端口并发送消息。你可以在服务器和客户端之间进行数据交换的练习。