// The rate limiter should still be functional after concurrent access
            assertTrue(concurrentLimiter.checkAttempt("finaluser", "192.168.3.1"),
                    "Rate limiter should still be functional after concurrent operations");

            // Verify that the rate limiter tracked some activity

        TestAuthenticationChain chain1 = new TestAuthenticationChain();
        TestAuthenticationChain chain2 = new TestAuthenticationChain();

        chain1.loadResult = null;
        chain2.loadResult = createTestUser("finaluser");

        authenticationManager.addChain(chain1);
        authenticationManager.addChain(chain2);

        User result = authenticationManager.load(user);

        assertEquals(chain2.loadResult, result);

    throw formatRuntimeException(
        "Latch failed to count down within %d second timeout", timeoutSeconds);
  }

  /**
   * Creates a garbage object that counts down the latch in its finalizer. Sequestered into a
   * separate method to make it somewhat more likely to be unreachable.
   */
  private static void createUnreachableLatchFinalizer(CountDownLatch latch) {
    Object unused =
        new Object() {

    throw formatRuntimeException(
        "Latch failed to count down within %d second timeout", timeoutSeconds);
  }

  /**
   * Creates a garbage object that counts down the latch in its finalizer. Sequestered into a
   * separate method to make it somewhat more likely to be unreachable.
   */
  private static void createUnreachableLatchFinalizer(CountDownLatch latch) {
    Object unused =
        new Object() {