*
     * @param id the unique identifier of the data configuration
     * @return an OptionalEntity containing the DataConfig if found, empty otherwise
     * @throws IllegalArgumentException if id is null or empty
     */
    public OptionalEntity<DataConfig> getDataConfig(final String id) {
        return dataConfigBhv.selectByPK(id);
    }

    /**

    }

    @Test
    public void test_empty() {
        // Test empty user bean creation
        FessUserBean emptyBean = FessUserBean.empty();
        assertNotNull(emptyBean);

        // Test getUserId returns EMPTY_USER_ID
        assertEquals(Constants.EMPTY_USER_ID, emptyBean.getUserId());

        // Test hasRoles always returns true for empty user
        assertTrue(emptyBean.hasRoles(new String[] { "admin" }));

     * @param dataCrawlStartTime The parameter value of dataCrawlStartTime. (NotNull)
     */
    public void setDataCrawlStartTime(String dataCrawlStartTime) {
        registerVariable("dataCrawlStartTime", dataCrawlStartTime);
    }

    /**
     * Set the value of dataCrawlEndTime, used in parameter comment. <br>

        // Assert deleteByQuery was called with the configured empty index
        assertTrue(deleteByQueryCalled);
        assertEquals("", deleteIndex);

        // Assert result is empty when successful
        assertEquals("", result);
    }

    @Test
    public void test_execute_withEmptyFieldName() {
        // Configure empty field name
        expiresFieldName = "";

            processor.init();

            // Should handle empty searcher list gracefully
            final List<Map<String, Object>> results = processor.search("*", new TestSearchRequestParams(0, 10, 0), OptionalThing.empty());
            assertNotNull(results);
        }
    }

    /**
     * Test setSearcher when list is initially empty.
     */
    @Test

     */
    public OptionalEntity<StemmerOverrideFile> getStemmerOverrideFile(final String dictId) {
        return dictionaryManager.getDictionaryFile(dictId)
                .filter(StemmerOverrideFile.class::isInstance)
                .map(file -> OptionalEntity.of((StemmerOverrideFile) file))
                .orElse(OptionalEntity.empty());
    }

    /**

                               aria-controls="listSearchForm"><i class="fas fa-search" aria-hidden="true"></i></a>
                            <div class="collapse <c:if test="${!empty urlExpr || !empty boostExpr}">show</c:if>" id="listSearchForm">
                                <la:form action="/admin/boostdoc/">
                                    <div class="form-group row">

     */
    public OptionalEntity<CharMappingFile> getCharMappingFile(final String dictId) {
        return dictionaryManager.getDictionaryFile(dictId)
                .filter(CharMappingFile.class::isInstance)
                .map(file -> OptionalEntity.of((CharMappingFile) file))
                .orElse(OptionalEntity.empty());
    }

    /**

    }

    /**
     * Test isSortField with empty array - should return false, not throw exception.
     * This test addresses the Copilot AI concern about empty arrays.
     */
    @Test
    public void test_isSortField_withEmptyArray_returnsFalse() {
        String[] emptyFields = {};
        queryFieldConfig.setSortFields(emptyFields);

        // Set should be empty but not null

     * Even if empty string, treated as empty plainly. So "IF pmb != null" is false if empty.
     * @param hostname The parameter value of hostname. (NotNull)
     */
    public void setHostname(String hostname) {
        registerVariable("hostname", hostname);
    }

    /**
     * Set the value of clustername, used in parameter comment. <br>