final Path baseDir = tempFolder.getRoot().toPath();
        final Path traversalPath = baseDir.resolve("../../../etc/passwd");

        assertFalse("Path traversal should be blocked", FileUtil.isPathSafe(traversalPath, baseDir));
    }

    /**
     * Test isPathSafe with File objects
     *
     * @throws Exception
     */
    @Test

  private static final long SMALL_TIMEOUT_MILLIS = 10;

  /** How long to wait when determining that a thread is blocked if we expect it to be blocked. */
  private static final long EXPECTED_HANG_DELAY_MILLIS = 75;

  /**
   * How long to wait when determining that a thread is blocked if we DON'T expect it to be blocked.
   */
  private static final long UNEXPECTED_HANG_DELAY_MILLIS = 10000;

  /**

    sendRequest(methodName, arguments);
    assertThat(getResponse(methodName).getThrowable()).isInstanceOf(expected);
  }

  /**
   * Causes this thread to call the named method, and asserts that this thread becomes blocked on
   * the lock-like object. The lock-like object must have a method equivalent to {@link
   * java.util.concurrent.locks.ReentrantLock#hasQueuedThread(Thread)}.
   */

    long timeout = SECONDS.toNanos(60);

    Supplier<Boolean> supplier =
        new Supplier<Boolean>() {
          boolean isWaiting(Thread thread) {
            switch (thread.getState()) {
              case BLOCKED:
              case WAITING:
              case TIMED_WAITING:
                return true;
              default:
                return false;
            }
          }

    long timeout = SECONDS.toNanos(60);

    Supplier<Boolean> supplier =
        new Supplier<Boolean>() {
          boolean isWaiting(Thread thread) {
            switch (thread.getState()) {
              case BLOCKED:
              case WAITING:
              case TIMED_WAITING:
                return true;
              default:
                return false;
            }
          }

   * state: BLOCKED, WAITING, or TIMED_WAITING.
   */
  @SuppressWarnings("ThreadPriorityCheck") // TODO: b/175898629 - Consider onSpinWait.
  void waitForThreadToEnterWaitState(Thread thread, long timeoutMillis) {
    long startTime = System.nanoTime();
    for (; ; ) {
      Thread.State s = thread.getState();

  @SuppressWarnings("ThreadPriorityCheck") // TODO: b/175898629 - Consider onSpinWait.
  void awaitTimedWaiting(Thread thread) {
    while (true) {
      switch (thread.getState()) {
        case BLOCKED:
        case NEW:
        case RUNNABLE:
        case WAITING:
          Thread.yield();
          break;
        case TIMED_WAITING:
          return;
        case TERMINATED:

    sendRequest(methodName, arguments);
    assertThat(getResponse(methodName).getThrowable()).isInstanceOf(expected);
  }

  /**
   * Causes this thread to call the named method, and asserts that this thread becomes blocked on
   * the lock-like object. The lock-like object must have a method equivalent to {@link
   * java.util.concurrent.locks.ReentrantLock#hasQueuedThread(Thread)}.
   */

    // This should wake up waiter1 and cause the waiter1 node to be removed.
    waiter1.interrupt();

    waiter1.join();
    waiter2.awaitWaiting(); // should still be blocked

    LockSupport.unpark(waiter2); // spurious wakeup
    waiter2.awaitWaiting(); // should eventually re-park

    future.set(null);
    waiter2.join();
  }

  @SuppressWarnings("ThreadPriorityCheck") // TODO: b/175898629 - Consider onSpinWait.
  void awaitTimedWaiting(Thread thread) {
    while (true) {
      switch (thread.getState()) {
        case BLOCKED:
        case NEW:
        case RUNNABLE:
        case WAITING:
          Thread.yield();
          break;
        case TIMED_WAITING:
          return;
        case TERMINATED: