protected CrawlerContext crawlerContext;

    protected boolean background = false;

    protected boolean daemon = false;

    protected int threadPriority = Thread.NORM_PRIORITY;

    protected Thread parentThread;

    protected ThreadGroup crawlerThreadGroup;

    public Crawler() {
        crawlerContext = new CrawlerContext();

   * 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>

          /* Someone beat us to it! Trying again...
           *
           * Technically this loop not guaranteed to terminate, so theoretically (extremely
           * unlikely) this thread might starve, but even then, there is always going to be another
           * thread doing progress here.
           */
        }
      }
    }
  }

  /**

    final CountDownLatch doneSignal = new CountDownLatch(1);

    Thread thread =
        new Thread() {
          @Override
          public void run() {
            try {
              cacheRef.get().getUnchecked(3);
            } finally {
              doneSignal.countDown();
            }
          }
        };
    thread.setUncaughtExceptionHandler(
        new UncaughtExceptionHandler() {

    final CountDownLatch doneSignal = new CountDownLatch(1);

    Thread thread =
        new Thread() {
          @Override
          public void run() {
            try {
              cacheRef.get().getUnchecked(3);
            } finally {
              doneSignal.countDown();
            }
          }
        };
    thread.setUncaughtExceptionHandler(
        new UncaughtExceptionHandler() {

  /**
   * Returns an exception handler that exits the system. This is particularly useful for the main
   * thread, which may start up other, non-daemon threads, but fail to fully initialize the
   * application successfully.
   *
   * <p>Example usage:
   *
   * <pre>
   * public static void main(String[] args) {
   *   Thread.currentThread().setUncaughtExceptionHandler(UncaughtExceptionHandlers.systemExit());
   *   ...
   * </pre>
   *

  /**
   * Invoked when a call is canceled.
   *
   * Like all methods in this interface, this is invoked on the thread that triggered the event. But
   * while other events occur sequentially; cancels may occur concurrently with other events. For
   * example, thread A may be executing [responseBodyStart] while thread B executes [canceled].
   * Implementations must support such concurrent calls.
   *

    }


    private static void interruptThreadSafely ( QueryThread thread ) {
        try {
            thread.interrupt();
        }
        catch ( SecurityException e ) {
            e.printStackTrace();
        }
    }


    private static void joinThread ( Thread thread ) {
        try {
            thread.join();
        }
        catch ( InterruptedException e ) {

  }

  @J2ktIncompatible
  @GwtIncompatible // Thread.interrupt
  public void testGetUnchecked_interrupted() {
    Thread.currentThread().interrupt();
    try {
      assertEquals("foo", getUnchecked(immediateFuture("foo")));
      assertTrue(Thread.currentThread().isInterrupted());
    } finally {
      Thread.interrupted();
    }
  }

  public void testGetUnchecked_cancelled() {

  }

  @J2ktIncompatible
  @GwtIncompatible // Thread.interrupt
  public void testGetUnchecked_interrupted() {
    Thread.currentThread().interrupt();
    try {
      assertEquals("foo", getUnchecked(immediateFuture("foo")));
      assertTrue(Thread.currentThread().isInterrupted());
    } finally {
      Thread.interrupted();
    }
  }

  public void testGetUnchecked_cancelled() {