e155. sending to a multicast group.txt

来自「这里面包含了一百多个JAVA源文件」· 文本 代码 · 共 13 行

You can send to a multicast socket using either a DatagramSocket or a MulticastSocket. What makes it multicast is the address that is in the datagram. If the address is a multicast address, the datagram will reach the multicast members in the group. You only need to use MulticastSocket if you want to control the time-to-live of the datagram. 
    byte[] outbuf = new byte[1024];
    int port = 1234;
    try {
        DatagramSocket socket = new DatagramSocket();
        InetAddress groupAddr = InetAddress.getByName("228.1.2.3");
        DatagramPacket packet = new DatagramPacket(outbuf, outbuf.length, groupAddr, port);
        socket.send(packet);
    } catch (SocketException e) {
    } catch (IOException e) {
    }