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()+'
').getBytes());
            for(int i=0; i<3; i++) {
                buffer.flip();
                ((DatagramChannel)multicast).send(buffer, group);
            }
            
        }catch(IOException e) {
            e.printStackTrace();
        }

    }

}