* to the string returned by {@link #serviceName}
   */
  protected Executor executor() {
    return command -> newThread(serviceName(), command).start();
  }

  @Override
  public String toString() {
    return serviceName() + " [" + state() + "]";
  }

  @Override
  public final boolean isRunning() {

   * to the string returned by {@link #serviceName}
   */
  protected Executor executor() {
    return command -> newThread(serviceName(), command).start();
  }

  @Override
  public String toString() {
    return serviceName() + " [" + state() + "]";
  }

  @Override
  public final boolean isRunning() {

   * debugging output.
   *
   * @since 14.0
   */
  protected String serviceName() {
    return getClass().getSimpleName();
  }

  @Override
  public String toString() {
    return serviceName() + " [" + state() + "]";
  }

  @Override
  public final boolean isRunning() {
    return delegate.isRunning();
  }

  @Override

			filePattern="${log.file.basedir}/${domain.name}${backup.date.suffix}-%i.log.gz">
			<PatternLayout><Pattern>${log.pattern}</Pattern></PatternLayout><!-- <EcsLayout serviceName="fess" eventDataset="suggest" /> -->
			<Policies>
				<TimeBasedTriggeringPolicy />
				<SizeBasedTriggeringPolicy size="100 MB" />
			</Policies>
			<DefaultRolloverStrategy fileIndex="max" min="1"

			filePattern="${log.file.basedir}/${domain.name}${backup.date.suffix}-%i.log.gz">
			<PatternLayout><Pattern>${log.pattern}</Pattern></PatternLayout><!-- <EcsLayout serviceName="fess" eventDataset="thumbnail" /> -->
			<Policies>
				<TimeBasedTriggeringPolicy />
				<SizeBasedTriggeringPolicy size="100 MB" />
			</Policies>
			<DefaultRolloverStrategy fileIndex="max" min="1"

			filePattern="${log.file.basedir}/${domain.name}${backup.date.suffix}-%i.log.gz">
			<PatternLayout><Pattern>${log.pattern}</Pattern></PatternLayout><!-- <EcsLayout serviceName="fess" eventDataset="crawler" /> -->
			<Policies>
				<TimeBasedTriggeringPolicy />
				<SizeBasedTriggeringPolicy size="100 MB" />
			</Policies>
			<DefaultRolloverStrategy fileIndex="max" min="1"

   * debugging output.
   *
   * @since 14.0
   */
  protected String serviceName() {
    return getClass().getSimpleName();
  }

  @Override
  public String toString() {
    return serviceName() + " [" + state() + "]";
  }

  @Override
  public final boolean isRunning() {
    return delegate.isRunning();
  }

  @Override

			filePattern="${log.file.basedir}/${domain.name}${backup.date.suffix}-%i.log.gz">
			<PatternLayout><Pattern>${log.pattern}</Pattern></PatternLayout><!-- <EcsLayout serviceName="fess" eventDataset="app" /> -->
			<Policies>
				<TimeBasedTriggeringPolicy />
				<SizeBasedTriggeringPolicy size="100 MB" />
			</Policies>
			<DefaultRolloverStrategy fileIndex="max" min="1"

          @Override
          protected ScheduledExecutorService executor() {
            return TestingExecutors.noOpScheduledExecutor();
          }

          @Override
          protected String serviceName() {
            return "Foo";
          }
        };
    TimeoutException e =
        assertThrows(
            TimeoutException.class, () -> service.startAsync().awaitRunning(1, MILLISECONDS));

    protected void run() throws Exception {
      latch.await();
    }

    @Override
    protected void triggerShutdown() {
      latch.countDown();
    }

    @Override
    protected String serviceName() {
      return this.getClass().getSimpleName() + "[" + index + "]";
    }
  }

  public void testNulls() {
    ServiceManager manager = new ServiceManager(Arrays.<Service>asList());