}).orElse(Collections.emptyList());
    }

    public OptionalEntity<StemmerOverrideFile> getStemmerOverrideFile(final String dictId) {
        return dictionaryManager.getDictionaryFile(dictId).filter(StemmerOverrideFile.class::isInstance)
                .map(file -> OptionalEntity.of((StemmerOverrideFile) file)).orElse(OptionalEntity.empty());
    }

import org.codelibs.fess.unit.UnitFessTestCase;

public class StemmerOverrideFileTest extends UnitFessTestCase {
    private StemmerOverrideFile stemmerOverrideFile;

    @Override
    public void setUp() throws Exception {
        super.setUp();
        stemmerOverrideFile = new StemmerOverrideFile("1", "dummy", new Date());
        List<StemmerOverrideItem> itemList = new ArrayList<>();

                                    <label for="stemmeroverrideFile" class="col-sm-3 text-sm-right col-form-label"><la:message
                                            key="labels.dict_stemmeroverride_file"/></label>
                                    <div class="col-sm-9">
                                        <input type="file" id="stemmeroverrideFile" name="stemmeroverrideFile" class="form-control-file"/>

        validateApi(form, messages -> {});
        final StemmerOverrideFile file = stemmerOverrideService.getStemmerOverrideFile(form.dictId).orElseGet(() -> {
            throwValidationErrorApi(messages -> messages.addErrorsFailedToUploadProtwordsFile(GLOBAL));
            return null;
        });
        try (InputStream inputStream = form.stemmerOverrideFile.getInputStream()) {
            file.update(inputStream);

/**
 * @author shinsuke
 * @author Keiichi Watanabe
 */
public class UploadForm {

    @Required
    public String dictId;

    @Required
    public MultipartFormFile stemmerOverrideFile;

        dictionaryManager.addCreator(this);
    }

    @Override
    protected DictionaryFile<? extends DictionaryItem> newDictionaryFile(final String id, final String path, final Date timestamp) {
        return new StemmerOverrideFile(id, path, timestamp).manager(dictionaryManager);
    }