final CountDownLatch latch = new CountDownLatch(1);
// Create a client with custom id, that connects to a server with given
// id and has a message listener that ensures that ALL messages are
// received in perfect order.
Client c = new Client(id, serverId, new ClientListener() {
@Override
public void messageReceived(String message) {
int num = Integer.parseInt(message.trim());
if (num != (cLast.get() + 1)) {
System.err.println("--- CLIENT-LISTENER(" + id + ") " +