UDP網絡編程DategramSocket——舉例——指定發送，不確定接收，接受端把數據顯示在控制檯上

    /*
        這裏涉及到的異常，應該使用try-catch-finally處理
         */

public class UDPTest {

    //發送端
    @Test
    public void sender() throws IOException {

        DatagramSocket socket = new DatagramSocket();


        String str = "我是UDP方式發送的導彈";
        byte[] data = str.getBytes();
        InetAddress inet = InetAddress.getLocalHost();
        DatagramPacket packet = new DatagramPacket(data,0,data.length,inet,9090);

        socket.send(packet);

        socket.close();

    }
    //接收端
    @Test
    public void receiver() throws IOException {

        DatagramSocket socket = new DatagramSocket(9090);

        byte[] buffer = new byte[100];
        DatagramPacket packet = new DatagramPacket(buffer,0,buffer.length);

        socket.receive(packet);

        System.out.println(new String(packet.getData(),0,packet.getLength()));

        socket.close();
    }
}