private static final ImmutableSet<String> VALID_NAME =
      ImmutableSet.of(
          // keep-sorted start
          "123.cn",
          "8server.shop",
          "a" + DELTA + "b.com",
          "abc.a23",
          "biz.com.ua",
          "f--1.com",
          "f--o",
          "f-_-o.cOM",
          "f11-1.com",
          "fOo",
          "f_a",

                // Do nothing
            }

            @Override
            public void stop() {
                stopCallCount.incrementAndGet();
            }
        };

        // Execute stop multiple times
        dataStore.stop();
        dataStore.stop();
        dataStore.stop();

        assertEquals(3, stopCallCount.get());
    }

    assertSame(stopwatch, stopwatch.stop());
    assertFalse(stopwatch.isRunning());
  }

  public void testStop_new() {
    assertThrows(IllegalStateException.class, stopwatch::stop);
    assertFalse(stopwatch.isRunning());
  }

  public void testStop_alreadyStopped() {
    stopwatch.start();
    stopwatch.stop();
    assertThrows(IllegalStateException.class, stopwatch::stop);
    assertFalse(stopwatch.isRunning());
  }

                "aaa");
        assertQueryBuilder(MatchPhraseQueryBuilder.class,
                "{\"match_phrase\":{\"title\":{\"query\":\"aaa\",\"slop\":0,\"zero_terms_query\":\"NONE\",\"boost\":1.0}}}", //

        setQueryType("bool");
        assertQueryContext(

    //                                                                      Search Execute
    //                                                                      ==============
    /**
     * Show the index page.
     * @param form The search form.
     * @return The HTML response.
     */
    @Execute
    @Secured({ ROLE, ROLE + VIEW })
    public HtmlResponse index(final SearchForm form) {

    // stop it.
    blockingCallable.waitForStart();

    // Give the second task a chance to (incorrectly) start up while the first task is running.
    assertThat(future2.isDone()).isFalse();

    // Stop the first task. The second task should then run.
    blockingCallable.stop();
    executor.shutdown();

    //                                                                      Search Execute
    //                                                                      ==============
    /**
     * Show the index page.
     * @param form The search form.
     * @return The HTML response.
     */
    @Execute
    @Secured({ ROLE, ROLE + VIEW })
    public HtmlResponse index(final SearchForm form) {

    //                                                                      ==============
    /**
     * Show the index page.
     * @return The HTML response.
     */
    @Execute
    @Secured({ ROLE, ROLE + VIEW })
    public HtmlResponse index() {
        return asListHtml();
    }

    /**
     * Show the list page.
     * @param pageNumber The page number.
     * @param form The search form.

    //                                                                      ==============
    /**
     * Show the index page.
     * @return The HTML response.
     */
    @Execute
    @Secured({ ROLE, ROLE + VIEW })
    public HtmlResponse index() {
        return asListHtml();
    }

    /**
     * Show the list page.
     * @param pageNumber The page number.
     * @param form The search form.