* interrupting thread. In theory, interruptTask() should be very fast, but due to
         * InterruptibleChannel and JavaLangAccess.blockedOn(Thread, Interruptible), it isn't
         * predictable what work might be done. (e.g., close a file and flush buffers to disk). To
         * protect ourselves from this, we park ourselves and tell our interrupter that we did so.

            }
            return true;
        }

        // Check dynamically blocked IPs (Cache handles expiration automatically)
        final Boolean blocked = blockedIps.getIfPresent(ip);
        if (blocked != null) {
            if (logger.isDebugEnabled()) {
                logger.debug("IP dynamically blocked: ip={}", ip);
            }
            return true;
        }

        return false;

        assertFalse("Path traversal should be blocked", result);
    }

    @Test
    public void test_isValidVirtualHostPath_pathTraversal_encoded() throws Exception {
        setupVirtualHostHelper("/site1", "/site2");

        Boolean result = invokeIsValidVirtualHostPath("/site1/../../../etc");
        assertFalse("Encoded path traversal should be blocked", result);
    }

    @Test

            logger.debug("Rate limit check: clientIp={}, path={}", clientIp, httpRequest.getRequestURI());
        }

        // Check if IP is blocked
        if (rateLimitHelper.isBlocked(clientIp)) {
            if (logger.isDebugEnabled()) {
                logger.debug("Request blocked: clientIp={}", clientIp);
            }
            sendBlockedResponse(httpResponse);
            return;
        }

        // Check rate limit

  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;

  /**

    // 1. the runner has been woken up
    // 2. the interrupter is stuck in the call the Thread.interrupt()

    // after some period of time the runner thread should become blocked on the task because it is
    // waiting for the slow interrupting thread to complete Thread.interrupt
    awaitBlockedOnInstanceOf(runner, InterruptibleTask.Blocker.class);

    // 1. the runner has been woken up
    // 2. the interrupter is stuck in the call the Thread.interrupt()

    // after some period of time the runner thread should become blocked on the task because it is
    // waiting for the slow interrupting thread to complete Thread.interrupt
    awaitBlockedOnInstanceOf(runner, InterruptibleTask.Blocker.class);

        // javascript: protocol should be blocked
        assertFalse(result.contains("javascript:"));
    }

    @Test
    public void test_render_xss_dataProtocol() {
        String malicious = "[Click me](data:text/html,<script>alert('XSS')</script>)";
        String result = markdownRenderer.render(malicious);
        // data: protocol should be blocked
        assertFalse(result.contains("data:text/html"));

  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;

  /**

            }
            throw new RejectedExecutionException();
          }
        };
    SequentialExecutor executor = new SequentialExecutor(delegate);
    ExecutorService blocked = newCachedThreadPool();
    Future<?> first = blocked.submit(() -> executor.execute(Runnables.doNothing()));
    future.get(10, SECONDS);
    assertThrows(RejectedExecutionException.class, () -> executor.execute(Runnables.doNothing()));