return redirect(ErrorAction.class);
        }
    }

    /**
     * Checks if the given URL represents a file system path.
     * Determines if the URL uses file system protocols that may require
     * special handling for content serving.
     *
     * @param url the URL to check
     * @return true if the URL is a file system path, false otherwise
     */

### Generate Source Code

    $ mvn dbflute:download # (one time command)
    $ mvn dbflute:freegen
    $ mvn license:format

### Integration Tests

Integration tests require a running Fess server with OpenSearch. Follow these steps:

#### 1. Build Fess

    $ mvn antrun:run  # Download OpenSearch plugins (if not done)
    $ mvn package     # Build the package

| Constants | UPPER_SNAKE_CASE | `DEFAULT_MAX_READING_NUM` |
| Packages | lowercase | `org.codelibs.fess.suggest` |

### JavaDoc Requirements

All public classes and methods require JavaDoc with `@param`, `@return`, and `@throws` tags.

### Best Practices

**Null Safety:**
```java
public Suggester(final Client client, final SuggestSettings settings) {

    /**
     * Constructs a new DataSerializer.
     * <p>
     * Initializes the ThreadLocal Kryo instances with appropriate configuration.
     * The Kryo instances are configured to not require class registration for
     * flexibility, and debug mode warnings are enabled when debug logging is active.
     * </p>
     */
    public DataSerializer() {
        kryoThreadLocal = ThreadLocal.withInitial(() -> {

        } catch (final Exception e) {
            return false;
        }
    }

    @Override
    public void close() {
        // GCS Storage client doesn't require explicit close
        // but we can try to close it if needed
        try {
            storage.close();
        } catch (final Exception e) {
            if (logger.isDebugEnabled()) {

            return OptionalEntity.empty();
        });
    }

    /**
     * Gets the action response for the specified SSO response type.
     *
     * SPNEGO authentication typically doesn't require special response handling
     * for metadata or logout operations, so this method returns null.
     *
     * @param responseType The type of SSO response requested

For most migration scenarios, we recommend using the modern JSON Search API (`/api/v1/documents`) instead.

### Admin APIs

All admin APIs require authentication (`-u admin:admin` or Bearer token).

**Base Path**: `/api/admin/`

**Available Endpoints**:
- `POST /backup/upload` - Upload backup/import files
- `GET /backup/export` - Export configurations

      <match value="X-Notes-Item:" type="string" offset="0">
        <match value="Message-ID:" type="string" offset="0:8192"/>
      </match>
      <!-- match X- DKIM- ARC- at start of file and then require at least one
           of the usual: from, received, date...but look farther into the file
           because of the X|DKIM|ARC headers-->
      <match value="(X|DKIM|ARC)-" type="regex" offset="0">