@Override
  public void notifyTerminated() {
    doAction(Executable::notifyTerminated);
  }
@Test
  public void shouldNotifyAllToShutdown() throws Exception {
    // When:
    multiExecutable.notifyTerminated();

    // Then:
    // Then:
    final InOrder inOrder = Mockito.inOrder(executable1, executable2);
    inOrder.verify(executable1).notifyTerminated();
    inOrder.verify(executable2).notifyTerminated();
    inOrder.verifyNoMoreInteractions();
  }