return failFastResponse!!
    }

    val result = responseQueue.take()

    // If take() returned because we're shutting down, then enqueue another dead letter so that any
    // other threads waiting on take() will also return.
    if (result == DEAD_LETTER) responseQueue.add(DEAD_LETTER)

    return result
  }

   * The particular nature and strength of the guarantees made by the proxy is
   * implementation-dependent. However, it is important that each of the methods on the target
   * object behaves appropriately when its thread is interrupted.
   *
   * <p>For example, to return the value of {@code target.someMethod()}, but substitute {@code
   * DEFAULT_VALUE} if this method call takes over 50 ms, you can use this code:
   *
   * <pre>

        @Test
        @DisplayName("Should handle received notification")
        void testReceived() throws InterruptedException {
            CountDownLatch latch = new CountDownLatch(1);

            Thread waiter = new Thread(() -> {
                synchronized (response) {
                    try {
                        if (!response.isReceived()) {
                            response.wait(1000);
                        }

    @Test
    void testActivityTracking() {
        long initialTime = channelInfo.getLastActivityTime();

        // Wait a bit and update activity
        try {
            Thread.sleep(10);
        } catch (InterruptedException e) {
            Thread.currentThread().interrupt();
        }

        channelInfo.updateActivity();
        assertTrue(channelInfo.getLastActivityTime() > initialTime);

// that pass integers back and forth.  No actual
// concurrency, just threads and synchronization
// and foreign code on multiple pthreads.

package main

import (
	big "."
	"runtime"
)

func fibber(c chan *big.Int, out chan string, n int64) {
	// Keep the fibbers in dedicated operating system
	// threads, so that this program tests coordination
	// between pthreads and not just goroutines.

    try {
      for (i in 1..2) {
        // Space out traffic to make it easier to demarcate.
        sendTestRequest(fbRequest)
        Thread.sleep(1000)
        sendTestRequest(twitterRequest)
        Thread.sleep(1000)
        sendTestRequest(googleRequest)
        Thread.sleep(2000)
      }
    } finally {
      client.connectionPool.evictAll()
      client.dispatcher.executorService.shutdownNow()

    private List<File> filesToDelete = new ArrayList<>();

    private final String baseFilename;

    private final String fileSuffix;

    private StackTraceElement callerInfo;

    private Thread cleanupWarning;

    private boolean warnAboutCleanup = false;

    public TestFileManager(String baseFilename, String fileSuffix) {
        this.baseFilename = baseFilename;
        this.fileSuffix = fileSuffix;

        .build()

    executor = newVirtualThreadPerTaskExecutor()

    // Capture non-deterministic but probable sysout warnings of pinned threads
    // https://docs.oracle.com/en/java/javase/21/core/virtual-threads.html
    System.setOut(PrintStream(capturedOut))
  }

  @AfterEach
  fun checkForPinning() {
    assertThat(capturedOut.toString()).isEmpty()
  }

 *   <li>Handle project forking states</li>
 * </ul>
 *
 * The service maintains the mutable state of projects as they progress through
 * their build lifecycle, ensuring thread-safety and proper state management.
 * All implementations must be thread-safe as they may be accessed concurrently
 * during parallel builds.
 *
 * @since 4.0.0
 * @see org.apache.maven.api.services.ProjectBuilder
 * @see Project
 */
@Experimental

        ThreadFactory threadFactory = r -> {
            Thread t = new Thread(r, "ResourceManager-Cleanup");
            t.setDaemon(true);
            return t;
        };
        cleanupExecutor = Executors.newSingleThreadScheduledExecutor(threadFactory);

        // Add shutdown hook for cleanup
        Runtime.getRuntime().addShutdownHook(new Thread(this::shutdown, "ResourceManager-Shutdown"));