e.getMessage().contains("Failed to extract") || e.getMessage().contains("No entries could be processed"));
        }
    }

    /**
     * Test that TarExtractor handles invalid archive gracefully.
     * Invalid archives may either throw an exception or return empty content.
     */
    public void test_TarExtractor_invalidArchive_handlesGracefully() {

        final long elapsed = (System.nanoTime() - start) / 1000000;

        assertTrue("file:// URLs should not be delayed", elapsed < 50);
    }

    /**
     * Test that null URL queue is handled gracefully
     */
    public void test_nullUrlQueue() {
        final HostIntervalController controller = new HostIntervalController();
        controller.delayMillisBeforeProcessing = 1000L;

void addUrl(String url)         // Add URL to queue
void cleanup(String sessionId)  // Clean up session
void stop()                     // Stop gracefully
```

**Key Fields**: `crawlerContext`, `urlFilter`, `intervalController`, `clientFactory`, `ruleManager`

### CrawlerContext (`CrawlerContext.java`)

Execution context and configuration.

**Important Fields**:
```java

         */
        public boolean isFinished() {
            return finished;
        }

        /**
         * Stops the crawling operation gracefully.
         * If a data store is currently active, this method calls
         * its stop method to halt the crawling process.
         */
        public void stopCrawling() {
            if (dataStore != null) {

        assertTrue(sitemaps.length >= 3); // At least the valid ones should be parsed

        // Test NumericBot - various crawl-delay formats
        // Should handle edge cases gracefully
        assertTrue(robotsTxt.getCrawlDelay("NumericBot") >= 0);

        // Test TabBot - tab characters should be treated as whitespace
        assertFalse(robotsTxt.allows("/tab1/", "TabBot"));

            crawlingInfoHelper.putToInfoMap(key, dateFormat.format(new Date()));
        }
    }

    /**
     * Waits for a crawler thread to complete execution.
     * This method handles interruptions gracefully and logs when a crawler process is interrupted.
     *
     * @param crawlerThread the thread to wait for; null threads are ignored
     */
    private void joinCrawlerThread(final Thread crawlerThread) {

                ist.interrupt();
            }
        }
        return -1; // Indicate failure
    }

    /**
     * Timer task for destroying processes that exceed their timeout.
     * Handles graceful and forceful termination of thumbnail generation processes.
     */
    protected static class ProcessDestroyer extends TimerTask {

        /** The process to monitor and destroy. */
        private final Process p;