}

    /**
     * Test name with control characters
     */
    public void test_name_controlCharacters() {
        // Test with various control characters
        testTransformer.setName("name\0with\0null");
        assertEquals("name\0with\0null", testTransformer.getName());

        testTransformer.setName("name\rwith\rcarriage\rreturn");
        assertEquals("name\rwith\rcarriage\rreturn", testTransformer.getName());

        // Test with suppression enabled and writable stack trace
        String message1 = "Test with suppression enabled";
        CrawlerSystemException exception1 = constructor.newInstance(message1, true, true);
        assertNotNull(exception1);
        assertEquals(message1, exception1.getMessage());
        assertNull(exception1.getCause());

        // Test with suppression disabled and writable stack trace

    }

    /**
     * Test basic initialization with session ID
     */
    public void test_init_withSessionId() {
        String sessionId = "test-session-001";
        urlFilter.init(sessionId);
        // Initialization should complete without errors
        assertNotNull(urlFilter);
    }

    /**
     * Test initialization with null session ID
     */
    public void test_init_withNullSessionId() {

 * It also provides a protected constructor that allows to specify whether or not suppression is enabled or stack trace is writable.
 */
public class CrawlerSystemException extends RuntimeException {

    private static final long serialVersionUID = 1L;

    /**
     * Constructs a new {@code CrawlerSystemException} with the specified detail message and cause.
     *

     * <ul>
     *   <li>&amp; with &amp;amp;</li>
     *   <li>&lt; with &amp;lt;</li>
     *   <li>&gt; with &amp;gt;</li>
     *   <li>" with &amp;quot;</li>
     *   <li>' with &amp;apos;</li>
     * </ul>
     * Additionally, it strips invalid XML characters from the input string.
     *
     * @param value the input string to be escaped
     * @return the escaped XML string with invalid characters removed
     */

# Run tests for specific module
mvn test -pl fess-crawler
```

## Examples

### Web Crawling with Custom Rules

```java
// Create crawler with custom configuration
StandardCrawlerContainer container = new StandardCrawlerContainer();

// Configure HTTP client with custom settings
container.singleton("httpClient", HcHttpClient.class, client -> {
    client.setUserAgent("MyBot/1.0");

    }

    /**
     * Test Rule with null rule ID
     */
    public void test_nullRuleId() {
        TestRule rule = new TestRule(null, new TestResponseProcessor("test"), true);

        assertNull(rule.getRuleId());

        ResponseData responseData = new ResponseData();
        assertTrue(rule.match(responseData));
    }

    /**
     * Test Rule with null ResponseProcessor
     */

            // Expected
        }

        try {
            CrawlerStatus.valueOf(" RUNNING "); // with spaces
            fail("Should throw IllegalArgumentException for value with spaces");
        } catch (IllegalArgumentException e) {
            // Expected
        }
    }

    /**
     * Test valueOf method with null
     */
    public void test_valueOf_null() {
        try {
            CrawlerStatus.valueOf(null);

 * and registration with the ExtractorFactory.
 *
 * <p>
 * This class handles the retrieval of essential crawler components like
 * {@link MimeTypeHelper} and {@link ExtractorFactory} from the
 * {@link CrawlerContainer}. It also provides a convenient method for
 * registering the extractor with the {@link ExtractorFactory}.
 * </p>
 *
 * <p>

        // ResponseData with only URL
        ResponseData urlOnlyData = new ResponseData();
        urlOnlyData.setUrl("http://example.com");
        ResultData result2 = testTransformer.transform(urlOnlyData);
        assertNotNull(result2);
        assertNotNull(result2.getData());

        // ResponseData with response body