mvn test                       # Run tests
mvn formatter:format           # Format code
mvn license:format             # Update license headers
```

### Code Style

- 4 spaces (no tabs), opening brace on same line, max line length 120
- JavaDoc required for public APIs
- License headers required (Apache 2.0)

### Testing

- **Structure**: `src/test/java/org/codelibs/fess/crawler/`

            <property name="tokens" value="LITERAL_CATCH"/>
        </module>
        <module name="AvoidNestedBlocks">
            <property name="allowInSwitchCase" value="true"/>
        </module>

        <!-- Braces -->
        <module name="LeftCurly"/>
        <module name="RightCurly"/>
        <module name="NeedBraces"/>

        <!-- Whitespace -->
        <module name="GenericWhitespace"/>

        assertEquals("DELETE", Method.DELETE.toString());
        assertEquals("HEAD", Method.HEAD.toString());
        assertEquals("OPTIONS", Method.OPTIONS.toString());
        assertEquals("TRACE", Method.TRACE.toString());
        assertEquals("CONNECT", Method.CONNECT.toString());
    }

    // --- URL with special characters tests ---

    @Test
    public void test_UrlWithSpaces() {

```

Do NOT translate with (German) - notice the dash:

```
## Typhinweise und –annotationen { #type-hints-and-annotations }
```

- Do not modify the hyphens in the content in headers inside of curly braces, which you shall not translate.

### German instructions, when to use and when not to use hyphens in words (written in first person, which is you).

   *     argument. These are matched by position - the first {@code %s} gets {@code
   *     errorMessageArgs[0]}, etc. Unmatched arguments will be appended to the formatted message in
   *     square braces. Unmatched placeholders will be left as-is.
   * @param errorMessageArgs the arguments to be substituted into the message template. Arguments
   *     are converted to strings using {@link String#valueOf(Object)}.

        //
        // Note that there is a race condition here which can result in missing
        // a cyclic edge: it's possible for two threads to simultaneous find
        // "safe" edges which together form a cycle. Preventing this race
        // condition efficiently without _introducing_ deadlock is probably
        // tricky. For now, just accept the race condition---missing a warning

    }

    /**
     * Creates a new CurlRequest with the HTTP TRACE method for the specified URL.
     *
     * @param url the URL to send the TRACE request to
     * @return a new CurlRequest object configured with the TRACE method and the specified URL
     */
    public static CurlRequest trace(final String url) {
        return new CurlRequest(Method.TRACE, url);
    }

    /**

        String errorMessage = "Stack trace test error";
        ServletException servletException = new ServletException(errorMessage);

        // Wrap it in ServletRuntimeException
        ServletRuntimeException runtimeException = new ServletRuntimeException(servletException);

        // Verify stack trace is available
        StackTraceElement[] stackTrace = runtimeException.getStackTrace();

    @Test
    public void test_stackTraceForMessageOnlyConstructor() {
        // Test that stack trace is not writable when using message-only constructor
        ThumbnailGenerationException exception = new ThumbnailGenerationException("Test message");

        // The message-only constructor uses super(message, false, false) which disables stack trace
        assertEquals(0, exception.getStackTrace().length);
    }

    @Test

        return actionClass;
    }

    /**
     * Overrides fillInStackTrace to return null for performance optimization.
     * This prevents stack trace generation for this exception type.
     *
     * @return null to skip stack trace generation
     */
    @Override
    public synchronized Throwable fillInStackTrace() {
        return null;
    }