response.getItems().forEach(item -> 
            System.out.println("Async suggestion: " + item.getText()[0])
        );
    })
    .error(throwable -> {
        // Handle error
        System.err.println("Error: " + throwable.getMessage());
    });
```

## Advanced Usage

### Index from Existing Documents

```java
import org.codelibs.fess.suggest.index.contents.document.ESSourceReader;

                if (psExitCode != 0) {
                    System.err.println("Docker command available but daemon not running in CI environment");
                    return false;
                }
            }

            return true;
        } catch (Exception e) {
            System.err.println("Docker availability check failed: " + e.getMessage());
            return false;
        }

            final ByteArrayOutputStream outStream = new ByteArrayOutputStream();
            System.setOut(new PrintStream(outStream, true));
            final PrintStream originalErrStream = System.err;
            final ByteArrayOutputStream errStream = new ByteArrayOutputStream();
            System.setErr(new PrintStream(errStream, true));
            try {

labels.backup_name=Nom
labels.backup_bulk_file=Fichier en vrac
labels.backup_button_upload=Téléverser
labels.process_time_is_exceeded=Le temps de traitement de la recherche a dépassé la limite. Les résultats affichés peuvent être partiels.
labels.user_given_name=Prénom
labels.givenName=Prénom (nom donné)
labels.user_surname=Nom de famille
labels.surame=Nom de famille
labels.user_mail=E-mail
labels.mail=E-mail

BAGF,uCACE,iBAAA,0BCvFN,eACE,SAAA,SAEA,6BxB8hFF,uCACA,4BwB5hFI,OAAA,gDACA,WAAA,gDACA,YAAA,KAGF,qBACE,SAAA,SACA,IAAA,EACA,KAAA,EACA,QAAA,EACA,OAAA,KACA,QAAA,KAAA,OACA,SAAA,OACA,WAAA,MACA,cAAA,SACA,YAAA,OACA,eAAA,KACA,OAAA,uBAAA,MAAA,YACA,iBAAA,EAAA,ELRE,WAAA,QAAA,IAAA,WAAA,CAAA,UAAA,IAAA,YAIA,uCKTJ,qBLUM,WAAA,MKON,6BxBiiFF,uCwB/hFI,QAAA,KAAA,OAEA,yDAAA,+CACE,MAAA,YxBmiFN,oDwBpiFI,0CACE,MAAA,YAGF,oEAAA,0DAEE,YAAA,SACA,eAAA,QxBqiFN,6CACA,+DwBziFI,mCAAA,qDAEE,YAAA,SACA,eAAA,QxB2iFN,wDwBxiFI,8CACE,YA...