final CoordinatorHelper helper = createCapturingHelper("node1@host1", null, null, createMockResponse(200, searchResponse));
        setLastEventCheckTime(helper, 4000L);

        helper.fetchNewEvents();

        // lastEventCheckTime should be max(createdTime) + 1 = 7001
        assertEquals(7001L, getLastEventCheckTime(helper));
    }

    @Test

        assertNotNull(helper.duplicateHostList);
        assertEquals(1, helper.duplicateHostList.size());
        assertEquals("www.test.com", helper.duplicateHostList.get(0).getRegularName());
    }

    @Test
    public void test_add_withNullList() {
        DuplicateHostHelper helper = new DuplicateHostHelper();
        helper.duplicateHostList = null;

import org.codelibs.fess.helper.LabelTypeHelper;
import org.codelibs.fess.helper.OsddHelper;
import org.codelibs.fess.helper.PopularWordHelper;
import org.codelibs.fess.helper.QueryHelper;
import org.codelibs.fess.helper.RoleQueryHelper;
import org.codelibs.fess.helper.SearchHelper;
import org.codelibs.fess.helper.UserInfoHelper;
import org.codelibs.fess.mylasta.action.FessUserBean;

        LogNotificationHelper helper = new LogNotificationHelper();
        // destroy() without init() should not throw NPE because of null checks
        helper.destroy();
    }

    @Test
    public void test_init_destroy_multipleRounds() {
        LogNotificationHelper helper = new LogNotificationHelper();
        helper.init();
        helper.destroy();
        // Second round
        helper.init();

### Service
- Inject behaviors (Bhv) for data access
- Use `OptionalEntity<T>` for nullable returns
- Plain classes (no extends/implements)

### Helper
- Stateless utility classes
- Access via `ComponentUtil.getXyzHelper()`
- Named with "Helper" suffix

### DBFlute Generated Code
```
opensearch/{index}/
├── bsentity/, bsbhv/    # Base classes (DO NOT EDIT)

        // Test default state
        assertTrue(helper.isCrawlerRunning());

        // Test setting to false
        helper.setCrawlerRunning(false);
        assertFalse(helper.isCrawlerRunning());

        // Test setting back to true
        helper.setCrawlerRunning(true);
        assertTrue(helper.isCrawlerRunning());
    }

    @Test

import org.codelibs.fess.app.web.api.ApiResult.Status;
import org.codelibs.fess.app.web.api.admin.FessApiAdminAction;
import org.codelibs.fess.exception.FessSystemException;
import org.codelibs.fess.helper.PermissionHelper;
import org.codelibs.fess.helper.SuggestHelper;
import org.codelibs.fess.opensearch.config.exentity.ElevateWord;
import org.codelibs.fess.util.ComponentUtil;
import org.lastaflute.web.Execute;

        } catch (final Exception e) {
            return;
        }

        final LogNotificationHelper helper;
        try {
            helper = ComponentUtil.getLogNotificationHelper();
        } catch (final Exception e) {
            return;
        }

        final List<LogNotificationEvent> events = helper.drainAll();
        if (events.isEmpty()) {
            return;
        }

        try {

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
 * either express or implied. See the License for the specific language
 * governing permissions and limitations under the License.
 */
package org.codelibs.fess.helper;

import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.codelibs.core.lang.StringUtil;

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
 * either express or implied. See the License for the specific language
 * governing permissions and limitations under the License.
 */
package org.codelibs.fess.helper;

import java.util.LinkedHashMap;
import java.util.Map;

import org.apache.commons.lang3.StringUtils;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;