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package derms.net.rmulticast;
import derms.net.ConcurrentMulticastSocket;
import derms.net.Packet;
import java.io.IOException;
import java.io.Serializable;
import java.net.*;
import java.time.Instant;
import java.util.Set;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.LinkedBlockingQueue;
import java.util.concurrent.atomic.AtomicReference;
import java.util.logging.Logger;
/** TODO */
public class ReliableMulticast<T extends Serializable & Hashable> {
private final Set<MessageID> positiveAcks; // Positively acknowledged messages.
private final Set<MessageID> negativeAcks; // Negatively acknowledged messages.
private final ReceivedSet<T> received;
private final BlockingQueue<Message<T>> retransmissions; // Messages pending retransmission.
private final AtomicReference<Instant> lastSend;
private final SocketAddress group;
private final ConcurrentMulticastSocket inSock, outSock;
private final InetAddress laddr; // Local address.
private final BlockingQueue<Message<T>> delivered;
private final Logger log;
public ReliableMulticast(InetSocketAddress group, InetAddress laddr) throws IOException {
this.positiveAcks = new ConcurrentHashMap<MessageID, Void>().keySet();
this.negativeAcks = new ConcurrentHashMap<MessageID, Void>().keySet();
this.received = new ReceivedSet<T>();
this.retransmissions = new LinkedBlockingQueue<Message<T>>();
this.lastSend = new AtomicReference<Instant>(Instant.now());
this.group = group;
this.inSock = new ConcurrentMulticastSocket();
this.inSock.joinGroup(group.getAddress());
this.outSock = new ConcurrentMulticastSocket(group.getPort());
this.outSock.joinGroup(group.getAddress());
this.laddr = laddr;
this.delivered = new LinkedBlockingQueue<Message<T>>();
this.log = Logger.getLogger(this.getClass().getName());
(new Thread(new Receive<T>(inSock, positiveAcks, negativeAcks, received, retransmissions, delivered))).start();
(new Thread(new Retransmit<T>(retransmissions, outSock, group))).start();
}
public void send(T payload) throws IOException {
Message<T> msg = new Message<T>(
payload,
laddr,
positiveAcks.toArray(new MessageID[0]),
negativeAcks.toArray(new MessageID[0]));
DatagramPacket pkt = Packet.encode(msg, group);
outSock.send(pkt);
positiveAcks.clear();
(new Thread(new Timeout<T>(msg, positiveAcks, retransmissions))).start();
lastSend.set(Instant.now());
}
public T receive() throws InterruptedException {
Message<T> msg = delivered.take();
return msg.payload;
}
}
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