```
src/main/resources/
├── fess_label.properties           # Base English labels (fallback)
├── fess_label_[locale].properties  # Language-specific labels (~1,056 lines)
├── fess_message.properties         # Base English messages (fallback)
└── fess_message_[locale].properties # Language-specific messages (~200 lines)
```

### Naming Convention

- **Language only**: `fess_label_en.properties`, `fess_label_ja.properties`

    @Override
    public ActionValidator<FessMessages> createValidator() {
        return systemHelper.createValidator(requestManager, this::createMessages, myValidationGroups());
    }

    /**
     * Creates a new messages instance for handling validation and user messages.
     * This method can be called by the application to create message containers.
     *
     * @return a new FessMessages instance
     */
    @Override

src/main/resources/
├── fess_config.properties     # Main config
├── app.xml                    # DI configuration
├── fess_label_*.properties    # UI labels (i18n)
├── fess_message_*.properties  # Validation messages (i18n)
└── fess_indices/              # OpenSearch index mappings

src/main/webapp/WEB-INF/view/  # JSP templates
```

## DBFlute Code Generation

import org.codelibs.fess.app.service.GroupService;
import org.codelibs.fess.app.web.CrudMode;
import org.codelibs.fess.app.web.base.FessAdminAction;
import org.codelibs.fess.mylasta.action.FessMessages;
import org.codelibs.fess.opensearch.user.exentity.Group;
import org.codelibs.fess.util.ComponentUtil;
import org.codelibs.fess.util.RenderDataUtil;
import org.dbflute.optional.OptionalEntity;

import org.codelibs.fess.app.web.CrudMode;
import org.codelibs.fess.app.web.base.FessAdminAction;
import org.codelibs.fess.app.web.base.login.FessLoginAssist;
import org.codelibs.fess.mylasta.action.FessMessages;
import org.codelibs.fess.opensearch.user.exentity.User;
import org.codelibs.fess.util.ComponentUtil;
import org.codelibs.fess.util.RenderDataUtil;
import org.dbflute.optional.OptionalEntity;

     * @param runtimeGroups   The runtime groups.
     * @return A new action validator.
     */
    public ActionValidator<FessMessages> createValidator(final RequestManager requestManager,
            final UserMessagesCreator<FessMessages> messagesCreator, final Class<?>[] runtimeGroups) {
        return new FessActionValidator<>(requestManager, messagesCreator, runtimeGroups);
    }

    /**

import org.codelibs.fess.helper.QueryHelper;
import org.codelibs.fess.helper.SearchHelper;
import org.codelibs.fess.helper.SystemHelper;
import org.codelibs.fess.mylasta.action.FessMessages;
import org.codelibs.fess.mylasta.direction.FessConfig;
import org.codelibs.fess.opensearch.client.SearchEngineClient;
import org.codelibs.fess.util.ComponentUtil;
import org.codelibs.fess.util.RenderDataUtil;