crawler.urlFilter.addInclude("https://example.com/.*");
        
        // Execute crawling
        String sessionId = crawler.execute();
        System.out.println("Crawling completed. Session ID: " + sessionId);
    }
}
```

### File System Crawling

```java
import org.codelibs.fess.crawler.client.fs.FileSystemClient;

// Configure for file system crawling