### Essential Info

- **Language**: Java 21+
- **Build**: Maven 3.x
- **License**: Apache 2.0
- **DI**: LastaFlute DI
- **Repo**: https://github.com/codelibs/fess-crawler

### Tech Stack

- **HTTP**: Apache HttpComponents 4.5+
- **Extraction**: Apache Tika 3.0+, POI 5.3+, PDFBox 3.0+
- **Testing**: JUnit 4, UTFlute, Mockito 5.7.0
- **Storage**: In-memory (default), OpenSearch (optional)

```java
import org.codelibs.fess.suggest.request.popularwords.PopularWordsResponse;

PopularWordsResponse popularWords = suggester.popularWords()
    .setSize(20)                    // top 20 words
    .setQuery("tech*")              // filter pattern
    .execute()
    .getResponse();

popularWords.getItems().forEach(item -> {
    System.out.println("Popular: " + item.getText() +