lockB.lock();
    lockA.unlock();
    lockB.unlock();

    // The opposite order should fail (Policies.THROW).
    PotentialDeadlockException firstException = null;
    lockB.lock();
    PotentialDeadlockException expected =
        assertThrows(PotentialDeadlockException.class, () -> lockA.lock());
    checkMessage(expected, "LockB -> LockA", "LockA -> LockB");
    firstException = expected;

    lockB.lock();
    lockA.unlock();
    lockB.unlock();

    // The opposite order should fail (Policies.THROW).
    PotentialDeadlockException firstException = null;
    lockB.lock();
    PotentialDeadlockException expected =
        assertThrows(PotentialDeadlockException.class, () -> lockA.lock());
    checkMessage(expected, "LockB -> LockA", "LockA -> LockB");
    firstException = expected;

      } else {
        // Unsafe acquisition order detected. Create and cache a
        // PotentialDeadlockException.
        PotentialDeadlockException exception =
            new PotentialDeadlockException(acquiredLock, this, path);
        disallowedPriorLocks.put(acquiredLock, exception);
        policy.handlePotentialDeadlock(exception);
      }
    }