### Code Standards
- Follow the project's Eclipse formatter configuration
- Add Apache License 2.0 headers to new files: `mvn license:format`
- Maintain comprehensive JavaDoc documentation
- Write thorough unit tests with good coverage
- Follow existing naming conventions and patterns

## 📄 License

            return result;
        }
    }

    private class TestableIndexUpdateCallbackImpl extends IndexUpdateCallbackImpl {
        @PostConstruct
        @Override
        public void init() {
            // Override init to use our test config directly
            maxDocumentRequestSize = 1048576L;
            maxDocumentCacheSize = 10000;
            // Set ingestFactory using reflection since it's private

import org.dbflute.dbmeta.name.ColumnRealName;
import org.dbflute.dbmeta.name.ColumnSqlName;
import org.dbflute.exception.InvalidQueryRegisteredException;
import org.dbflute.util.Srl;
import org.opensearch.common.unit.Fuzziness;
import org.opensearch.index.query.BoolQueryBuilder;
import org.opensearch.index.query.CommonTermsQueryBuilder;
import org.opensearch.index.query.ExistsQueryBuilder;
import org.opensearch.index.query.IdsQueryBuilder;

$result: $result + 1;\n    }\n  }\n  $result: $result * $factor * $sign;\n  $dividend-unit: unit($dividend);\n  $divisor-unit: unit($divisor);\n  $unit-map: (\n    \"px\": 1px,\n    \"rem\": 1rem,\n    \"em\": 1em,\n    \"%\": 1%\n  );\n  @if ($dividend-unit != $divisor-unit and map-has-key($unit-map, $dividend-unit)) {\n    $result: $result * map-get($unit-map, $dividend-unit);\n  }\n  @return $result;\n}\n\n// Remove px-unit from $rfs-base-font-size for calculations\n@if $rfs-base-font-size-unit == \"px\"...

import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.concurrent.atomic.AtomicLong;

import org.codelibs.fess.entity.DataStoreParams;
import org.codelibs.fess.unit.UnitFessTestCase;

public class IndexUpdateCallbackTest extends UnitFessTestCase {

    public void test_interface_methods() {
        // Test with anonymous implementation

 */
package org.codelibs.fess.util;

import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;

import org.codelibs.fess.Constants;
import org.codelibs.fess.unit.UnitFessTestCase;

public class SystemUtilTest extends UnitFessTestCase {

    public void test_getSearchEngineHttpAddress_null() {
        // Clear the system property to test null case

 */
package org.codelibs.fess.util;

import static org.junit.Assert.assertArrayEquals;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Date;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.codelibs.fess.unit.UnitFessTestCase;

public class DocumentUtilTest extends UnitFessTestCase {

    public void test_string() {

import org.codelibs.fess.opensearch.config.exentity.ElevateWord;
import org.codelibs.fess.opensearch.log.exbhv.SearchLogBhv;
import org.codelibs.fess.opensearch.log.exentity.SearchLog;
import org.codelibs.fess.unit.UnitFessTestCase;
import org.codelibs.fess.util.ComponentUtil;

public class SuggestHelperTest extends UnitFessTestCase {

    private SuggestHelper suggestHelper;

    @Override

                languageHelper.getReindexScriptSource());
    }

    public void test_init() {
        try {
            languageHelper.init();
            // Should not throw exception
        } catch (Exception e) {
            fail("init() should not throw an exception: " + e.getMessage());
        }
    }

    public void test_updateDocument_withExistingLang() {

9. Open a Pull Request

### Code Style

- Use Eclipse formatter configuration (`src/config/eclipse/formatter/java.xml`)
- Follow existing naming conventions
- Add comprehensive JavaDoc for public APIs
- Write unit and integration tests

## License