}

  @Override
  protected final void tearDown() {
    tearDownStack.runTearDown();
  }

  private String enter() {
    return interruptible ? "enterInterruptibly" : "enter";
  }

  private String tryEnter() {
    return "tryEnter";
  }

  private String enterIf() {
    return interruptible ? "enterIfInterruptibly" : "enterIf";
  }