assertNull(dataStoreParams.getAsString("nonExistentKey"));
        assertEquals("defaultValue", dataStoreParams.getAsString("nonExistentKey", "defaultValue"));

        dataStoreParams.put("nullKey", null);
        assertEquals("defaultValue", dataStoreParams.getAsString("nullKey", "defaultValue"));
    }

        assertNotNull(capturedCallback.get());
        assertNotNull(capturedParams.get());
        assertEquals("value1", capturedParams.get().getAsString("key1"));
        assertEquals("value2", capturedParams.get().getAsString("key2"));
    }

    @Test
    public void test_store_withNullConfig() {
        // Test store with null config
        final AtomicBoolean storeCalled = new AtomicBoolean(false);

     * @param key The key of the setting.
     * @param defaultValue The default value if the setting is not found.
     * @return The setting value as a String.
     */
    public String getAsString(final String key, final String defaultValue) {
        return getAs(key, defaultValue, s -> s);
    }

    /**
     * Retrieves a setting value as an int.
     * @param key The key of the setting.

        assertEquals("settings-test.suggest", settings.getAsString(SuggestSettings.DefaultKeys.INDEX, ""));
        assertEquals("content", settings.array().get(SuggestSettings.DefaultKeys.SUPPORTED_FIELDS)[0]);
        assertEquals("label,virtual_host", settings.getAsString(SuggestSettings.DefaultKeys.TAG_FIELD_NAME, ""));
        assertEquals("role", settings.getAsString(SuggestSettings.DefaultKeys.ROLE_FIELD_NAME, ""));
    }

    @Test

         *
         * @param value The Date object to convert.
         * @return The ISO 8601 formatted date string, or null if value is not a Date.
         */
        @Override
        public String getAsString(final Object value) {
            if (value instanceof Date) {
                return DEFAULT_DATE_PRINTER.print(((Date) value).getTime());
            }
            return null;
        }

        /**

            defaultDataMap.put(fessConfig.getIndexFieldExpires(), documentExpires);
        }
        // segment
        defaultDataMap.put(fessConfig.getIndexFieldSegment(), initParamMap.getAsString(Constants.SESSION_ID));
        // created
        defaultDataMap.put(fessConfig.getIndexFieldCreated(), systemHelper.getCurrentTime());
        // boost

        badWords = settings.badword().get(true);
        tagFieldNames = settings.getAsString(SuggestSettings.DefaultKeys.TAG_FIELD_NAME, StringUtil.EMPTY).split(",");
        roleFieldName = settings.getAsString(SuggestSettings.DefaultKeys.ROLE_FIELD_NAME, StringUtil.EMPTY);
        langFieldName = settings.getAsString(SuggestSettings.DefaultKeys.LANG_FIELD_NAME, StringUtil.EMPTY);

         * </ul>
         */
        private void deleteOldDocs() {
            if (Constants.FALSE.equals(initParamMap.getAsString(DELETE_OLD_DOCS))) {
                return;
            }
            final String sessionId = initParamMap.getAsString(Constants.SESSION_ID);
            if (StringUtil.isBlank(sessionId)) {

        this.normalizer = Objects.requireNonNull(normalizer, "normalizer must not be null");
        this.analyzer = Objects.requireNonNull(analyzer, "analyzer must not be null");
        index = settings.getAsString(SuggestSettings.DefaultKeys.INDEX, StringUtil.EMPTY);
        this.threadPool = Objects.requireNonNull(threadPool, "threadPool must not be null");

        if (logger.isDebugEnabled()) {

     * @return the parameter value as a string, or the default value if not found
     */
    protected String getParamValue(final DataStoreParams paramMap, final String key, final String defaultValue) {
        return paramMap.getAsString(key, defaultValue);
    }

    /**
     * Adds a document to the search index by crawling the specified URL and processing the content.