Old Style of Using jgroups: 
String props="UDP:PING:FD:STABLE:NAKACK:UNICAST:" +
             "FRAG:FLUSH:GMS:VIEW_ENFORCER:STATE_TRANSFER:QUEUE";

Message send_msg;
Object  recv_msg;
Channel channel=new JChannel(props);

channel.connect("MyGroup");

send_msg=new Message(null, null, "Hello world");

channel.send(send_msg);

recv_msg=channel.receive(0);
System.out.println("Received " + recv_msg);

channel.disconnect();

channel.close();

The new style is to use ReceiverAdapter. see SimpleChat.java for more info.

The protocol stack is :

          "UDP(mcast_addr=228.8.8.10;mcast_port=25600;ip_ttl=32;bind_addr=" + haddr + ";tos=8;" +
              "ucast_recv_buf_size=25000000;ucast_send_buf_size=640000;mcast_send_buf_size=640000;" +
              "mcast_recv_buf_size=25000000;loopback=false;discard_incompatible_packets=true;" +
              "max_bundle_size=64000;max_bundle_timeout=30;use_incoming_packet_handler=true;" +
              "use_outgoing_packet_handler=false;down_thread=false;up_thread=false;enable_bundling=true):" +
           "PING(timeout=2000;down_thread=false;up_thread=false;num_initial_members=10):" +
           "MERGE2(max_interval=30000;down_thread=false;up_thread=false;min_interval=10000):" +
           "FD_SOCK(down_thread=false;up_thread=false):" +
           "FD(timeout=10000;max_tries=5;down_thread=false;up_thread=false;shun=true):" +
           "VERIFY_SUSPECT(timeout=1500;down_thread=false;up_thread=false):" +
           "pbcast.NAKACK(max_xmit_size=60000;use_mcast_xmit=true;gc_lag=0;" +
               "retransmit_timeout=300,600,1200,2400,4800;down_thread=false;" +
               "up_thread=false;discard_delivered_msgs=true):" +
           "UNICAST(timeout=300,600,1200,2400,3600;down_thread=false;up_thread=false):" +
           "pbcast.STABLE(stability_delay=1000;desired_avg_gossip=50000;down_thread=false;" +
               "up_thread=false;max_bytes=400000):" +
           "VIEW_SYNC(avg_send_interval=60000;down_thread=false;up_thread=false):" +
           "pbcast.GMS(print_local_addr=true;join_timeout=3000;down_thread=false;up_thread=false;" +
               "join_retry_timeout=2000;shun=false;view_bundling=true):" +
           "FC(max_credits=2000000;down_thread=false;up_thread=false;min_threshold=0.10;max_block_time=10000):" +
           "FRAG2(frag_size=60000;down_thread=false;up_thread=false);"  ;