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();

                }
              });
      thread.start();
      // we want to wait until each thread is WAITING - one thread waiting inside CacheLoader.load
      // (in startSignal.await()), and the others waiting for that thread's result.
      while (thread.isAlive() && thread.getState() != Thread.State.WAITING) {
        Thread.yield();
      }
    }
    gettersStartedSignal.countDown();

     * simple approach would be for each caller CAS it from null to a Set populated with its
     * exception. But there's another race: If the first thread fails with an exception and a second
     * thread immediately fails with the same exception:
     *
     * Thread1: calls setException(), which returns true, context switch before it can CAS
     * seenExceptionsField to its exception
     *

          protected void doStart() {
            new Thread() {
              @Override
              public void run() {
                notifyStarted();
                // We need to wait for the main thread to leave the ServiceManager.startAsync call
                // to
                // ensure that the thread running the failure callbacks is not the main thread.
                Uninterruptibles.awaitUninterruptibly(afterStarted);

        final ClassLoader context = Thread.currentThread().getContextClassLoader();
        try {
            final ClassLoader cl = new URLClassLoader(new URL[0], getClass().getClassLoader());
            Thread.currentThread().setContextClassLoader(cl);
            assertThat(ClassLoaderUtil.getClassLoader(TestCase.class), is(sameInstance(cl)));
        } finally {
            Thread.currentThread().setContextClassLoader(context);

    CountDownLatch doneSignal = new CountDownLatch(1);
    Thread thread =
        new Thread(
            () -> {
              try {
                cache.get(key, loader);
              } catch (UncheckedExecutionException | ExecutionException e) {
                doneSignal.countDown();
              }
            });
    thread.start();

    boolean done = doneSignal.await(1, SECONDS);

import org.apache.logging.log4j.Logger;

/**
 * A thread that reads from an input stream line by line and maintains a buffer of recent lines.
 * This class provides functionality to read input stream data asynchronously,
 * optionally process each line with a callback function, and maintain a circular buffer
 * of recent lines for retrieval.
 */
public class InputStreamThread extends Thread {
    /** Logger instance for this class */

              @Override
              public Integer call() {
                return Thread.currentThread().getStackTrace().length;
              }
            },
            directExecutor());
    settableFuture.set(null);
    assertThat(getDone(stackDepthCheck))
        .isLessThan(Thread.currentThread().getStackTrace().length + 100);
  }

        }

        @Test
        @DisplayName("Should be thread-safe with optimized locking")
        void testSignThreadSafety() throws InterruptedException {
            int threadCount = 10;
            Thread[] threads = new Thread[threadCount];
            byte[][] dataArrays = new byte[threadCount][128];

            for (int i = 0; i < threadCount; i++) {