emptyGenerator = new EmptyGenerator();

        // Test adding conditions - this should work without container
        emptyGenerator.addCondition("field1", "pattern1");
        emptyGenerator.addCondition("field1", "pattern2");
        emptyGenerator.addCondition("field2", "pattern.*");

        // We can't test isTarget properly without container,
        // but we can verify conditions are added
        assertNotNull(emptyGenerator);

        // Pattern with single backslash (14 chars): should match
        String singleBackslash = "image/svg" + "\\" + "+xml";
        assertEquals("Single backslash pattern should be 14 chars", 14, singleBackslash.length());
        assertTrue(svgMimetype.matches(singleBackslash));

        // Pattern with double backslash (15 chars): should NOT match
        String doubleBackslash = "image/svg" + "\\\\" + "+xml";

            return false;
        }

        Pattern pattern = (Pattern) propMap.get(USER_CODE_PATTERN);
        if (pattern == null) {
            pattern = Pattern.compile(getUserCodePattern());
            propMap.put(USER_CODE_PATTERN, pattern);
        }
        return pattern.matcher(userCode).matches();
    }

    String getQueryCollapseInnerHitsSorts();

    }

    /**
     * Converts a GSA URL pattern into a regular expression pattern suitable for Fess.
     * Handles various GSA pattern formats including regexp, contains, and URL-based patterns.
     *
     * @param s the input GSA pattern string
     * @return a regular expression pattern string, or empty string for comments/invalid patterns
     */
    protected String getFilterPath(final String s) {

        Pattern pattern = Pattern.compile(FS_FILE_RULE_PATTERN);
        assertTrue(pattern.matcher("text/html").matches());
    }

    @Test
    public void test_fsFileRulePattern_lhaTypes() {
        Pattern pattern = Pattern.compile(FS_FILE_RULE_PATTERN);
        assertTrue(pattern.matcher("application/lha").matches());
        assertTrue(pattern.matcher("application/x-lha").matches());

        final Set<String> valueSet = new HashSet<>();
        for (final LabelTypePattern pattern : labelTypePatternList) {
            if (pattern.match(path)) {
                valueSet.add(pattern.getValue());
            }
        }
        return valueSet;
    }

    /**
     * Builds a list of label type patterns.
     *
     * @param labelTypeList The list of label types.
     */

     * - Second: List of regex pattern matches (Pattern -> content template)
     */
    protected Map<String, Pair<Map<String, String>, List<Pair<Pattern, String>>>> relatedContentMap = Collections.emptyMap();

    /**
     * Prefix used to identify regex patterns in related content terms.
     * When a term starts with this prefix, it is treated as a regular expression
     * pattern rather than an exact match term.
     */

    /**
     * Cache for client rules mapping client names to their corresponding URL patterns.
     * This cache improves performance by avoiding repeated parsing of client configuration rules.
     * The key is the rule string, and the value is a pair containing the client name and compiled pattern.
     */
    protected ConcurrentHashMap<String, Pair<String, Pattern>> clientRuleCache = new ConcurrentHashMap<>();

    /**

        System.setProperty("java.version", "11.0.1");

        // Test version patterns with different separators
        String[] args = new String[] { "11:-Dprop=value:with:colons", "8-:-Xbootclasspath/a:/path/to/jar", "malformed11:-invalid", // Should not match pattern
                "11-malformed:-invalid" // Should not match pattern
        };

        String[] result = JvmUtil.filterJvmOptions(args);

└── fess_indices/              # OpenSearch index mappings

src/main/webapp/WEB-INF/view/  # JSP templates
src/test/java/.../it/          # Integration tests (*Tests.java)
```

## Architecture Patterns

### Action (Controller)
- Hierarchy: `TypicalAction` → `FessBaseAction` → `FessAdminAction`/`FessSearchAction`
- `@Execute` marks web endpoints
- `@Resource` for DI