UDP简单服务端客户端代码示例

UDP的理论不再多说，我这里直接给出一个关于UDP的HelloWorld程序，代码明了，希望对刚入门的学生有所帮助！

当然，实际上，在这块我也刚入门！

首先写服务端代码，服务端邦定本地的IP和端口来监听访问：

package udp;

import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetSocketAddress;


public class UdpServerSocket {
	
	private byte[] buffer = new byte[1024];
	private static DatagramSocket ds = null;
	private DatagramPacket packet = null;
	private InetSocketAddress socketAddress = null;
	
	
	public static void main(String[] args) throws Exception {
		String serverHost = "127.0.0.1";
		int serverPort = 3344;
		UdpServerSocket udpServerSocket = new UdpServerSocket(serverHost,
				serverPort);
		while (true) {
			udpServerSocket.receive();
			udpServerSocket.response("你好,吃了吗!");
		}		
	}

	
	public UdpServerSocket(String host, int port) throws Exception {
		socketAddress = new InetSocketAddress(host, port);
		ds = new DatagramSocket(socketAddress);
		System.out.println("服务端启动!");
	}

	
	public final String receive() throws IOException {
		packet = new DatagramPacket(buffer, buffer.length);
		ds.receive(packet);
		String info = new String(packet.getData(), 0, packet.getLength());
		System.out.println("接收信息：" + info);
		return info;
	}

	
	public final void response(String info) throws IOException {
		System.out.println("客户端地址 : " + packet.getAddress().getHostAddress()
				+ ",端口：" + packet.getPort());
		DatagramPacket dp = new DatagramPacket(buffer, buffer.length, packet
				.getAddress(), packet.getPort());
		dp.setData(info.getBytes());
		ds.send(dp);
	}
}

运行后提示服务端运行成功，程序开始监听端口，接收方法堵塞，当有访问时才会向下进行！

我们写客户端进行访问，看到网上的例子都是直接创建了 DatagramSocket 对象，而其实自己都不知道自己使用的端口是那个，这里我创建时会指定自己邦定的端口，其实很简单，就是初始化该对象时传递一个端口参数。

这里你访问客户端时客户端会打印你的IP和端口！

看一看客户端代码：

package udp;

import java.io.*;
import java.net.*;


public class UdpClientSocket {
	private byte[] buffer = new byte[1024];

	private static DatagramSocket ds = null;
	
	
	public static void main(String[] args) throws Exception {
		UdpClientSocket client = new UdpClientSocket();
		String serverHost = "127.0.0.1";
		int serverPort = 3344;
		client.send(serverHost, serverPort, ("你好，亲爱的!").getBytes());
		byte[] bt = client.receive();
		System.out.println("服务端回应数据：" + new String(bt));
		// 关闭连接
		try {
			ds.close();
		} catch (Exception ex) {
			ex.printStackTrace();
		}
	}

	
	public UdpClientSocket() throws Exception {
		ds = new DatagramSocket(8899); // 邦定本地端口作为客户端
	}
	
	
	public final void send(final String host, final int port,
			final byte[] bytes) throws IOException {
		DatagramPacket dp = new DatagramPacket(bytes, bytes.length, InetAddress.getByName(host), port);
		ds.send(dp);
	}

	
	public final byte[] receive()
			throws Exception {
		DatagramPacket dp = new DatagramPacket(buffer, buffer.length);
		ds.receive(dp);		
		byte[] data = new byte[dp.getLength()];
		System.arraycopy(dp.getData(), 0, data, 0, dp.getLength());		
		return data;
	}
}

直接运行程序看效果！

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持考高分网。