/**
   * remove any direct messages (dm in twitter slang) that were sent and received by the user prior
   * to a certain date)
   */
  public void deleteDirectMessages() {
    try {
      boolean found = true;
      int start = 1;
      int increment = twitterConfig.getIncrementCount();
      // Removing messages sent to user
      while (found) {
        found = false;
        ResponseList<DirectMessage> responses =
            twitter.getDirectMessages(new Paging(start, start + increment));
        for (DirectMessage dm : responses) {
          if (earlier.getTime() > dm.getCreatedAt().getTime()) {
            twitter.destroyDirectMessage(dm.getId());
            logger.debug("delete dm: " + dm.getId());
            found = true;
          }
        }
      }
      found = true;
      start = 1;
      increment = twitterConfig.getIncrementCount();
      // Removing messages sent by user.
      while (found) {
        found = false;
        ResponseList<DirectMessage> responses =
            twitter.getSentDirectMessages(new Paging(start, start + increment));
        for (DirectMessage dm : responses) {
          if (earlier.getTime() > dm.getCreatedAt().getTime()) {
            twitter.destroyDirectMessage(dm.getId());
            logger.debug("delete dm: " + dm.getId());
            found = true;
          }
        }
      }

    } catch (TwitterException e) {
      logger.error("Twitter exception occurred", e);
    }
  }