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

    @Override
    public K getKey() {
      assertTrue(Thread.holdsLock(mutex));
      return super.getKey();
    }

    @Override
    public V getValue() {
      assertTrue(Thread.holdsLock(mutex));
      return super.getValue();
    }

    @Override

import org.codelibs.core.log.Logger;

/**
 * Utility class for Thread class
 *
 * @author shinsuke
 *
 */
public abstract class ThreadUtil {

    private static final Logger logger = Logger.getLogger(ThreadUtil.class);

    public static void sleep(final long millis) {
        if (millis < 1L) {
            return;
        }
        try {
            Thread.sleep(millis);
        } catch (final InterruptedException e) {

    LockingThread thread = new LockingThread(lockA);
    thread.start();

    thread.waitUntilHoldingLock();
    assertFalse(lockA.tryLock());

    thread.releaseLockAndFinish();
    assertTrue(lockA.tryLock());
  }

  public void testReentrantWriteLock_tryLock() throws Exception {
    LockingThread thread = new LockingThread(writeLockA);
    thread.start();

    LockingThread thread = new LockingThread(lockA);
    thread.start();

    thread.waitUntilHoldingLock();
    assertFalse(lockA.tryLock());

    thread.releaseLockAndFinish();
    assertTrue(lockA.tryLock());
  }

  public void testReentrantWriteLock_tryLock() throws Exception {
    LockingThread thread = new LockingThread(writeLockA);
    thread.start();

    private static final int MAX_LOOP_COUNT = 10;

    protected Thread runningThread;

    protected AtomicBoolean running = new AtomicBoolean();

    public AccessTimeoutTarget(final Thread thread) {
        runningThread = thread;
        running.set(true);
    }

    /*
     * (non-Javadoc)
     *

    }

    @Override
    public int size() {
      assertTrue(Thread.holdsLock(mutex));
      return super.size();
    }

    @Override
    public boolean isEmpty() {
      assertTrue(Thread.holdsLock(mutex));
      return super.isEmpty();
    }

    @Override
    public @Nullable V remove(Object object) {
      assertTrue(Thread.holdsLock(mutex));
      return super.remove(object);
    }

    @Override

        server.start();

        final String url = "http://localhost:7070/";
        try {
            final ResponseData responseData = httpClient.doHead(url);
            Thread.sleep(100);
            assertNotNull(responseData.getLastModified());
            assertTrue(responseData.getLastModified().getTime() < new Date().getTime());
        } finally {
            server.stop();
        }

            }
        }, 1, true);

        assertNotNull(TimeoutManager.getInstance().thread);
        Thread.sleep(2000);
        assertTrue(expiredCount > 0);
        assertEquals(1, TimeoutManager.getInstance().getTimeoutTaskCount());
        TimeoutManager.getInstance().stop();
        assertNull(TimeoutManager.getInstance().thread);
        Thread.sleep(10);
        int count = expiredCount;
        task.stop();

  class Interruptenator extends Thread {
    final AtomicBoolean shutdown;

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

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

            });
        } catch (final Exception e) {
            logger.warn("Failed to write a thread dump to {}", file, e);
        }
    }

    public static void processThreadDump(final Consumer<String> writer) {
        for (final Map.Entry<Thread, StackTraceElement[]> entry : Thread.getAllStackTraces().entrySet()) {
            writer.accept("Thread: " + entry.getKey());
            final StackTraceElement[] trace = entry.getValue();