IP组播 MulticastChannel接口 DatagramChannel实现

监听者

 import java.io.IOException;
 import java.net.InetAddress;
 import java.net.InetSocketAddress;
 import java.net.NetworkInterface;
 import java.net.StandardProtocolFamily;
 import java.net.StandardSocketOptions;
 import java.nio.ByteBuffer;
 import java.nio.channels.Channels;
 import java.nio.channels.DatagramChannel;
 import java.nio.channels.MulticastChannel;
 import java.nio.channels.WritableByteChannel;
 import java.util.Enumeration;

 public class MulticastSniffer {

     public static void main(String[] args) throws IOException {
         //NetworkInterface interf = NetworkInterface.getByInetAddress(InetAddress.getLocalHost());
         NetworkInterface interf = NetworkInterface.getByInetAddress(InetAddress.getByName("192.168.1.181"));
         //设置本地硬件端口；

         InetSocketAddress group = new InetSocketAddress(InetAddress.getByName("224.0.0.1"), 2000);
         //设置组播地址
         DatagramChannel channel = DatagramChannel.open(StandardProtocolFamily.INET)
                 .setOption(StandardSocketOptions.SO_REUSEADDR, true)
                 .setOption(StandardSocketOptions.IP_MULTICAST_LOOP, false)
                 .bind(group)
                 .setOption(StandardSocketOptions.IP_MULTICAST_IF, interf);

         channel.configureBlocking(true);

         try(MulticastChannel multicast = channel){
             multicast.join(group.getAddress(), interf);

             byte[] data = new byte[8192];
             ByteBuffer buffer = ByteBuffer.allocate(8192);
             WritableByteChannel out = Channels.newChannel(System.out);
             while((((DatagramChannel)multicast).receive(buffer))!= null) {
                 buffer.flip();
                 out.write(buffer);
                 buffer.clear();
             }

         }catch(IOException e) {
             e.printStackTrace();
         }

     }

 }

发送者

 import java.io.IOException;
 import java.net.InetAddress;
 import java.net.InetSocketAddress;
 import java.net.NetworkInterface;
 import java.net.StandardProtocolFamily;
 import java.net.StandardSocketOptions;
 import java.nio.ByteBuffer;
 import java.nio.channels.DatagramChannel;
 import java.nio.channels.MulticastChannel;

 public class MulticastSender {

     public static void main(String[] args) throws IOException {

        // NetworkInterface interf = NetworkInterface.getByInetAddress(InetAddress.getLocalHost());

         NetworkInterface interf = NetworkInterface.getByInetAddress(InetAddress.getByName("192.168.1.181"));
         //设置本地硬件端口；

         InetSocketAddress group = new InetSocketAddress(InetAddress.getByName("224.0.0.1"), 2000);
         //设置组播地址
         DatagramChannel channel = DatagramChannel.open(StandardProtocolFamily.INET)
                 .setOption(StandardSocketOptions.SO_REUSEADDR, true)
                 .bind(group)
                 .setOption(StandardSocketOptions.IP_MULTICAST_IF, interf);

         //.setOption(StandardSocketOptions.IP_MULTICAST_LOOP, false)
         channel.configureBlocking(true);

         try(MulticastChannel multicast = channel){
             multicast.join(group.getAddress(), interf);

             ByteBuffer buffer = ByteBuffer.allocate(8192);
             buffer.put((InetAddress.getLocalHost().toString()+'\n').getBytes());
             for(int i=0; i<3; i++) {
                 buffer.flip();
                 ((DatagramChannel)multicast).send(buffer, group);
             }

         }catch(IOException e) {
             e.printStackTrace();
         }

     }

 }