private void checkActiveFileTransferNotifications(final int... expectedFileTransferIds) {
    final Set<Integer> currentFileTransferIds = notificationService.getCurrentFileTransferIds();
    assertEquals(expectedFileTransferIds.length, currentFileTransferIds.size());

    for (final Integer expectedFileTransferId : expectedFileTransferIds) {
      assertTrue(currentFileTransferIds.contains(expectedFileTransferId));
    }
  }
 private void checkThatNoFileTransferNotificationsAreActive() {
   assertTrue(notificationService.getCurrentFileTransferIds().isEmpty());
 }