* @param key the field name to match against
     * @param regex the regular expression pattern
     */
    public void addRule(final String key, final String regex) {
        regexMap.put(key, Pattern.compile(regex));
    }

    /**
     * Adds a compiled regular expression rule for the specified field.
     * @param key the field name to match against

                + "<doc>\n"//
                + "<field name=\"title\"><list><item>タイトル</item></list></field>\n"//
                + "<field name=\"body\"><list><item>第一章 第一節 ほげほげふがふが LINK 第2章 第2節</item></list></field>\n"//
                + "<field name=\"pcount\">2.0</field>\n"//
                + "<field name=\"true\">true</field>\n"//
                + "<field name=\"false\">false</field>\n"//
                + "</doc>";

    /**
     * Field name for ID.
     */
    public static final String ID = "id";

    /**
     * Field name for transformer name.
     */
    public static final String TRANSFORMER_NAME = "transformerName";

    /**
     * Field name for data.
     */
    public static final String DATA = "data";

    /**
     * Field name for encoding.
     */

                + "<field name=\"email\"><list><item></item><item>******@****.***</item></list></field>\n"//
                + "<field name=\"url\">http://www.taro.com/</field>\n"//
                + "<field name=\"tel\">090-xxxx-xxxx</field>\n"//
                + "</doc>";

        final ResponseData responseData = new ResponseData();
        responseData.setResponseBody(ResourceUtil.getResourceAsFile("extractor/test.xml"), false);

            builder.field(SESSION_ID, sessionId);
        }
        if (method != null) {
            builder.field(METHOD, method);
        }
        if (url != null) {
            builder.field(URL, url);
        }
        if (parentUrl != null) {
            builder.field(PARENT_URL, parentUrl);
        }
        if (depth != null) {
            builder.field(DEPTH, depth);
        }

    }

    /**
     * Test protected field access
     */
    public void test_protectedFieldAccess() {
        TestTransformer transformer = new TestTransformer();

        // Direct field access (simulating subclass behavior)
        transformer.name = "directFieldAccess";
        assertEquals("directFieldAccess", transformer.getName());

        // Setter should update the field
        transformer.setName("setterAccess");

    }

    /**
     * Extracts a field value from OpenSearch results and converts it to the specified type.
     *
     * @param <T> The target type.
     * @param field The field value from OpenSearch.
     * @param clazz The target class.
     * @return The converted field value.
     */
    @SuppressWarnings("unchecked")
    private <T> T getFieldValue(final Object field, final Class<T> clazz) {

        }
        if (httpStatusCode != null) {
            builder.field(HTTP_STATUS_CODE, httpStatusCode);
        }
        if (method != null) {
            builder.field(METHOD, method);
        }
        if (mimeType != null) {
            builder.field(MIME_TYPE, mimeType);
        }
        if (createTime != null) {
            builder.field(CREATE_TIME, createTime);
        }

     * @param name The name of the field.
     * @param value The value of the field.
     * @return The result data body.
     */
    protected String getResultDataBody(final String name, final String value) {
        // TODO: Support other XML footer types
        // TODO: Support other field types and trimming options

     */
    public OpenSearchUrlFilter() {
        // NOP
    }

    /**
     * Field name for session ID.
     */
    public static final String SESSION_ID = "sessionId";

    /**
     * Field name for filter type.
     */
    public static final String FILTER_TYPE = "filterType";

    /**
     * Field name for URL.
     */
    public static final String URL = "url";

    /**