UDP：不可靠, 效率高, 數據報/非連接

Demo_1:

Server 端：

import java.io.IOException;
import java.net.*;
public class TestUDPServer {
	public static void main(String[] args) {
		byte buf[] = new byte[1024];
		try {
			DatagramSocket ds = new DatagramSocket(5678);
			DatagramPacket dp = new DatagramPacket(buf, buf.length);
			while(true){
				try {
					ds.receive(dp);
					System.out.println(new String(buf,0,dp.getLength()));
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
		} catch (SocketException e) {
			e.printStackTrace();
		}
	}
}

Client 端：

import java.io.IOException;
import java.net.*;
public class TestUDPClient {
	public static void main(String[] args) {
		byte[] buf = (new String("hello java")).getBytes();
		DatagramPacket dp = new DatagramPacket(buf, buf.length, new InetSocketAddress("192.168.56.1", 5678));
		DatagramSocket ds;
		try {
			ds = new DatagramSocket(9999);
			try {
				ds.send(dp);
			} catch (IOException e) {
				e.printStackTrace();
			}
			ds.close();
		} catch (SocketException e) {
			e.printStackTrace();
		}
	}
}

運行結果：

Java中的網絡編程-3