/**
   * Tries to match the event object to already existing ComparableEvtObj in the supplied list.
   *
   * @param obj the object that we will try to match.
   * @param list the list we will search in.
   * @return the found ComparableEvtObj
   */
  private static ComparableEvtObj findRecentMessage(EventObject obj, List<ComparableEvtObj> list) {
    Contact contact = null;
    ChatRoom chatRoom = null;

    if (obj instanceof MessageDeliveredEvent) {
      contact = ((MessageDeliveredEvent) obj).getDestinationContact();
    } else if (obj instanceof MessageReceivedEvent) {
      contact = ((MessageReceivedEvent) obj).getSourceContact();
    } else if (obj instanceof ChatRoomMessageDeliveredEvent) {
      chatRoom = ((ChatRoomMessageDeliveredEvent) obj).getSourceChatRoom();
    } else if (obj instanceof ChatRoomMessageReceivedEvent) {
      chatRoom = ((ChatRoomMessageReceivedEvent) obj).getSourceChatRoom();
    }

    for (ComparableEvtObj evt : list) {
      if ((contact != null && contact.equals(evt.getContact()))
          || (chatRoom != null && chatRoom.equals(evt.getRoom()))) return evt;
    }

    return null;
  }