void testConcurrentAccess() throws InterruptedException {
        // Test thread safety of getInstance
        LogStream.setInstance(testStream);

        final LogStream[] instances = new LogStream[10];
        Thread[] threads = new Thread[10];

        for (int i = 0; i < threads.length; i++) {
            final int index = i;
            threads[i] = new Thread(() -> {
                instances[index] = LogStream.getInstance();

            }
          }
        });
    awaitUninterruptibly(enteredLatch);
  }

  @CanIgnoreReturnValue
  static Thread startThread(Runnable runnable) {
    Thread thread = new Thread(runnable);
    thread.setDaemon(true);
    thread.start();
    return thread;
  }

  /**
   * Generates a test case verifying that calling any enterXxx, tryEnterXxx, or waitForXxx method

            }
        }, 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();

          @Override
          public void run() {
            list.execute();
          }
        };
    Thread thread1 = new Thread(execute);
    Thread thread2 = new Thread(execute);
    thread1.start();
    thread2.start();
    assertEquals(0, runCalled.get());
    okayToRun.countDown();
    thread1.join();
    thread2.join();
    assertEquals(1, runCalled.get());
  }

  public void testAddAfterRun() throws Exception {

            }

            // When
            for (Thread thread : threads) {
                thread.start();
            }
            for (Thread thread : threads) {
                thread.join();
            }

            // Then
            for (int i = 0; i < threadCount; i++) {
                assertTrue(success[i], "Thread " + i + " failed");
            }
        }

        @Test

  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(
          new Runnable() {

    assertFalse(future.isDone());
    assertFalse(future.isCancelled());

    CountDownLatch successLatch = new CountDownLatch(1);

    // Run cancellation in a separate thread as an extra thread-safety test.
    new Thread(
            () -> {
              assertThrows(CancellationException.class, future::get);
              successLatch.countDown();
            })
        .start();

      takeEvent()
    }
  }

  private fun logEvent(e: ConnectionEvent) {
    if (e.connection != null) {
      assertThat(Thread.holdsLock(e.connection), "Called with lock $${e.connection}")
        .isFalse()
    }
    for (lock in forbiddenLocks) {
      assertThat(Thread.holdsLock(lock), "Called with lock $lock")
        .isFalse()
    }

    if (enforceOrder) {
      checkForStartEvent(e)
    }

     *            the length of time to sleep in milliseconds
     * @throws InterruptedRuntimeException
     *             if any thread has interrupted the current thread.
     */
    public static void sleep(final long millis) {
        if (millis < 1L) {
            return;
        }
        try {
            Thread.sleep(millis);
        } catch (final InterruptedException e) {
            throw new InterruptedRuntimeException(e);
        }

                }
            });
        }

        // Start all threads
        for (Thread thread : threads) {
            thread.start();
        }

        // Wait for all threads to complete
        for (Thread thread : threads) {
            thread.join(5000); // 5 second timeout
        }

        // Verify no errors occurred during concurrent execution
        assertFalse(hasError.get());