/**
   * Used by methods testing state transiotions
   *
   * @param newStatus the IcqStatusEnum field corresponding to the status that we'd like the
   *     opeation set to enter.
   * @throws Exception in case changing the state causes an exception
   */
  public void subtestStateTransition(IcqStatusEnum newStatus) throws Exception {
    logger.trace(" --=== beginning state transition test ===--");

    PresenceStatus oldStatus = operationSetPresence.getPresenceStatus();
    String oldStatusMessage = operationSetPresence.getCurrentStatusMessage();
    String newStatusMessage = statusMessageRoot + newStatus;

    logger.debug(
        "old status is=" + oldStatus.getStatusName() + " new status=" + newStatus.getStatusName());

    // First register a listener to make sure that all corresponding
    // events have been generated.
    PresenceStatusEventCollector statusEventCollector = new PresenceStatusEventCollector();
    operationSetPresence.addProviderPresenceStatusListener(statusEventCollector);

    // change the status
    operationSetPresence.publishPresenceStatus(newStatus, newStatusMessage);

    // test event notification.
    statusEventCollector.waitForPresEvent(10000);
    statusEventCollector.waitForStatMsgEvent(10000);

    // sometimes we don't get response from the server for the
    // changed status. we will query it once again.
    // and wait for the response
    if (statusEventCollector.collectedPresEvents.size() == 0) {
      logger.trace("Will query again status as we haven't received one");
      operationSetPresence.queryContactStatus(fixture.icqAccountID.getUserID());
      statusEventCollector.waitForPresEvent(10000);
    }

    operationSetPresence.removeProviderPresenceStatusListener(statusEventCollector);

    assertEquals(
        "Events dispatched during an event transition.",
        1,
        statusEventCollector.collectedPresEvents.size());
    assertEquals(
        "A status changed event contained wrong old status.",
        oldStatus,
        ((ProviderPresenceStatusChangeEvent) statusEventCollector.collectedPresEvents.get(0))
            .getOldStatus());
    assertEquals(
        "A status changed event contained wrong new status.",
        newStatus,
        ((ProviderPresenceStatusChangeEvent) statusEventCollector.collectedPresEvents.get(0))
            .getNewStatus());

    // verify that the operation set itself is aware of the status change
    assertEquals(
        "opSet.getPresenceStatus() did not return properly.",
        newStatus,
        operationSetPresence.getPresenceStatus());

    IcqStatusEnum actualStatus =
        fixture.testerAgent.getBuddyStatus(fixture.icqAccountID.getUserID());
    assertEquals(
        "The underlying implementation did not switch to the " + "requested presence status.",
        newStatus,
        actualStatus);

    // check whether the server returned the status message that we've set.
    assertEquals(
        "No status message events.", 1, statusEventCollector.collectedStatMsgEvents.size());
    assertEquals(
        "A status message event contained wrong old value.",
        oldStatusMessage,
        ((PropertyChangeEvent) statusEventCollector.collectedStatMsgEvents.get(0)).getOldValue());
    assertEquals(
        "A status message event contained wrong new value.",
        newStatusMessage,
        ((PropertyChangeEvent) statusEventCollector.collectedStatMsgEvents.get(0)).getNewValue());

    // verify that the operation set itself is aware of the new status msg.
    assertEquals(
        "opSet.getCurrentStatusMessage() did not return properly.",
        newStatusMessage,
        operationSetPresence.getCurrentStatusMessage());

    logger.trace(" --=== finished test ===--");
    // make it sleep a bit cause the aol server gets mad otherwise.
    pauseBetweenStateChanges();
  }