// lockA -> lockD should warn but otherwise succeed because lockD was
    // created by a factory with the WARN policy.
    lockA.lock();
    lockD.lock();
  }

  public void testReentrantLock_tryLock() throws Exception {
    LockingThread thread = new LockingThread(lockA);
    thread.start();

    thread.waitUntilHoldingLock();
    assertFalse(lockA.tryLock());

    thread.releaseLockAndFinish();