thread1.callAndAssertReturns(enter());
    thread2.callAndAssertBlocks(enter());
    thread1.callAndAssertReturns(leave());
    thread2.assertPriorCallReturns(enter());
  }

  public final void testTryEnter() throws Exception {
    thread1.callAndAssertReturns(true, tryEnter());
    thread2.callAndAssertReturns(false, tryEnter());
    thread1.callAndAssertReturns(true, tryEnter());

        // Multiple threads read the lastLoadedTime
        for (int i = 0; i < 10; i++) {
            final int index = i;
            threads[i] = new Thread(() -> {
                observedTimes[index] = testFactory.lastLoadedTime;
            });
        }

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

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

              }
              countingRunnable.integer.addAndGet(localRunnable.integer.get());
            }
          };
      threads.add(thread);
    }
  }

  @AfterExperiment
  void after() {
    for (Thread thread : threads) {
      thread.interrupt(); // try to get them to exit
    }
    threads.clear();
  }

  @Footprint
  Object measureSize() {
    return executor;
  }

  @Benchmark

  /**
   * When we need a new thread to run tasks, we call [Backend.execute]. A few microseconds later we
   * expect a newly-started thread to call [Runnable.run]. We shouldn't request new threads until
   * the already-requested ones are in service, otherwise we might create more threads than we need.
   *
   * We use [executeCallCount] and [runCallCount] to defend against starting more threads than we

                }
            });
        }

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

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

        // Verify no exceptions occurred
        for (int i = 0; i < threadCount; i++) {

    /**
     * Interval in milliseconds between crawler thread executions.
     * Used to control the rate at which new crawler threads are started
     * and the frequency of status checks.
     */
    protected long crawlingExecutionInterval = Constants.DEFAULT_CRAWLING_EXECUTION_INTERVAL;

    /**
     * Thread priority for crawler threads.
     * Defaults to normal thread priority.
     */

   * intentionally, so there is no other way to clean up these threads. (The better solution,
   * though, would be to run the tests that use TestThread in separate VMs so that their threads
   * don't hang around during other tests.)
   */
  @Override
  public void tearDown() throws Exception {
    try {
      Thread.class.getMethod("stop").invoke(this);
      join();

            } else {
                t.url = args[ai];
            }
        }

        final Thread[] threads = new Thread[t.numThreads];
        int ti;

        for (ti = 0; ti < t.numThreads; ti++) {
            threads[ti] = new Thread(t);
            logger.info(threads[ti].getName());
            threads[ti].start();
        }

        while (t.numComplete < t.numThreads) {
            long delay;

#### Do-stuff-later pool

Sometimes there's an action required like calling the application layer or responding to a ping, and the thread discovering the action is not the thread that should do the work. We enqueue a runnable on this executor and it gets handled by one of the executor's threads.

### Locks

                    }
                }
            });
        }

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

        // Wait for completion
        for (Thread t : threads) {
            t.join();
        }

        // Verify consistency
        SimpleCircuitBreaker.Statistics stats = breaker.getStatistics();