code: public SynchronizedCollection<ADDRESST> getAddresses(UUID participant) {
  		final Object mutex = mutex();
  		synchronized (mutex) {
  			return Collections3.synchronizedCollection(this.participants.get(participant), mutex);
  		}
  	}
docs: Replies all the addresses of the participant with the given identifier.
  
  @param participant the identifier of the participant.
  @return the collection of addresses. It may be <code>null</code> if the participant is unknown.