* and replacing them with their corresponding Alphabet representations based on the internal mapping.
 * When a Katakana character has multiple Alphabet representations, the converter generates multiple
 * possible readings.
 * </p>
 *
 * <p>
 * The class also utilizes ICU4J's {@link com.ibm.icu.text.Transliterator} to convert full-width characters

        // 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 analyze with different language settings
        String text = "hello world";
        String field = "content";

        // Test with English
        List<AnalyzeToken> tokensEn = analyzer.analyze(text, field, "en");
        assertNotNull(tokensEn);
        assertEquals(2, tokensEn.size());

        // Test with Japanese

/*
 * Copyright 2012-2025 CodeLibs Project and the Others.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,

    }

    /**
     * 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
     */

        assertEquals("", testTransformer.getName());
    }

    /**
     * Test name with special characters
     */
    public void test_name_specialCharacters() {
        // Test with spaces
        testTransformer.setName("name with spaces");
        assertEquals("name with spaces", testTransformer.getName());

        // Test with special characters
        testTransformer.setName("name-with_special.chars#123");

            // 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);

    }

    /**
     * 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() {

        // 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

# 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");