return b.toString();
        }).collect(Collectors.joining(",")));
        buf.append("},");
        final Threads threads = jvmStats.getThreads();
        buf.append("\"threads\":{");
        append(buf, "count", () -> threads.getCount()).append(',');
        append(buf, "peak", () -> threads.getPeakCount());
        buf.append("},");
        final Classes classes = jvmStats.getClasses();

    // Run a task on the composed Executor that interrupts its thread (i.e. this thread).
    fakePool.execute(() -> Thread.currentThread().interrupt());
    // Run a task that expects that it is not interrupted while it is running.
    e.execute(() -> assertThat(Thread.currentThread().isInterrupted()).isFalse());

    // Run these together.
    fakePool.runAll();

    @Override
    public String toString() {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.toString();
    }

    @Override
    public boolean equals(@Nullable Object o) {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.equals(o);
    }

    @Override
    public int hashCode() {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.hashCode();
    }

  static final class Interruptenator extends Thread {
    final AtomicBoolean shutdown;

    Interruptenator(Thread interruptee) {
      this(interruptee, new AtomicBoolean(false));
    }

    @SuppressWarnings("ThreadPriorityCheck") // TODO: b/175898629 - Consider onSpinWait.
    Interruptenator(Thread interruptee, AtomicBoolean shutdown) {
      super(
          () -> {

        InputStreamThread thread = jobProcess.getInputStreamThread();
        thread.start();
        thread.join(1000);

        String output = thread.getOutput();
        assertTrue("Should contain recent lines", output.contains("line5"));

        assertTrue("Should have line3", thread.contains("line3"));
        assertTrue("Should have line4", thread.contains("line4"));

    }

    // Test constructor with different thread context
    @Test
    public void test_constructorInDifferentThread() throws Exception {
        // Test that constructor works in different thread
        final CrawlerEngineClient[] clientHolder = new CrawlerEngineClient[1];
        final Exception[] exceptionHolder = new Exception[1];

        Thread thread = new Thread(() -> {
            try {

          @Override
          void afterRanInterruptiblyFailure(Throwable error) {}
        };
    Thread runner = new Thread(task, "runner");
    runner.start();
    isInterruptibleRegistered.await();
    // trigger the interrupt on another thread since it will block
    Thread interrupter =
        new Thread("Interrupter") {
          @Override
          public void run() {
            task.interruptTask();

          @Override
          void afterRanInterruptiblyFailure(Throwable error) {}
        };
    Thread runner = new Thread(task, "runner");
    runner.start();
    isInterruptibleRegistered.await();
    // trigger the interrupt on another thread since it will block
    Thread interrupter =
        new Thread("Interrupter") {
          @Override
          public void run() {
            task.interruptTask();

    Stopwatch stopwatch = Stopwatch.createStarted();
    Thread thread = new Thread(new JoinTarget(15));
    thread.start();
    thread.join();
    assertFalse(thread.isAlive());

    joinUninterruptibly(thread);
    joinUninterruptibly(thread, 0, MILLISECONDS);
    joinUninterruptibly(thread, -42, MILLISECONDS);
    joinUninterruptibly(thread, LONG_DELAY_MS, MILLISECONDS);

            }

            seen = true;

            tg = aTgList;
            Thread[] ts = new Thread[tg.activeCount()];
            tg.enumerate(ts);

            for (Thread active : ts) {
                String name = active.getName();
                boolean daemon = active.isDaemon();
                assertTrue(daemon, name + " is no daemon Thread.");
            }
        }