final String value = processVirtualHost(s -> s, StringUtil.EMPTY);
            LaRequestUtil.getOptionalRequest().ifPresent(req -> req.setAttribute(FessConfig.VIRTUAL_HOST_VALUE, value));
            return value;
        });
    }

    protected <T> T processVirtualHost(final Function<String, T> func, final T defaultValue) {

    // DELETE /api/admin/dict/protwords/setting/{dictId}/{id}
    @Execute
    public JsonResponse<ApiResult> delete$setting(final String dictId, final long id) {
        protwordsService.getProtwordsItem(dictId, id).ifPresent(entity -> {
            protwordsService.delete(dictId, entity);
            saveInfo(messages -> messages.addSuccessCrudDeleteCrudTable(GLOBAL));
        }).orElse(() -> {

        })).status(Status.OK).result());
    }

    // DELETE /api/admin/joblog/log/{id}
    @Execute
    public JsonResponse<ApiResult> delete$log(final String id) {
        jobLogService.getJobLog(id).ifPresent(entity -> {
            try {
                jobLogService.delete(entity);
                saveInfo(messages -> messages.addSuccessCrudDeleteCrudTable(GLOBAL));
            } catch (final Exception e) {

            if (user.hasRoles(ComponentUtil.getFessConfig().getAuthenticationAdminRolesAsArray())) {
                return Constants.SEARCH_PREFERENCE_LOCAL;
            }
            return user.getUserId();
        }).ifPresent(p -> searchRequestBuilder.setPreference(p)).orElse(() -> LaRequestUtil.getOptionalRequest().map(r -> {
            final HttpSession session = r.getSession(false);
            if (session != null) {

    // DELETE /api/admin/dict/kuromoji/setting/{dictId}/{id}
    @Execute
    public JsonResponse<ApiResult> delete$setting(final String dictId, final long id) {
        kuromojiService.getKuromojiItem(dictId, id).ifPresent(entity -> {
            kuromojiService.delete(dictId, entity);
            saveInfo(messages -> messages.addSuccessCrudDeleteCrudTable(GLOBAL));
        }).orElse(() -> {

            logger.warn("Failed to process gsa.xml file: {}", fileName, e);
        } finally {
            deleteTempFile(tempFile);
        }
        configParser.getWebConfig().ifPresent(c -> webConfigBhv.insert(c));
        configParser.getFileConfig().ifPresent(c -> fileConfigBhv.insert(c));
        labelTypeBhv.batchInsert(Arrays.stream(configParser.getLabelTypes()).collect(Collectors.toList()));
    }

            final RequestManager requestManager = ComponentUtil.getRequestManager();
            try {
                requestManager.findUserBean(FessUserBean.class)
                        .ifPresent(fessUserBean -> stream(fessUserBean.getPermissions()).of(stream -> stream.forEach(roleSet::add)))
                        .orElse(() -> {

    }

    // DELETE /api/admin/reqheader/setting/{id}
    @Execute
    public JsonResponse<ApiResult> delete$setting(final String id) {
        reqHeaderService.getRequestHeader(id).ifPresent(entity -> {
            try {
                reqHeaderService.delete(entity);
                saveInfo(messages -> messages.addSuccessCrudDeleteCrudTable(GLOBAL));
            } catch (final Exception e) {

    }

    // DELETE /api/admin/webauth/setting/{id}
    @Execute
    public JsonResponse<ApiResult> delete$setting(final String id) {
        webAuthService.getWebAuthentication(id).ifPresent(entity -> {
            try {
                webAuthService.delete(entity);
                saveInfo(messages -> messages.addSuccessCrudDeleteCrudTable(GLOBAL));
            } catch (final Exception e) {

            return true;
        }, (queryRequestBuilder, execTime, searchResponse) -> {
            final List<Map<String, String>> sessionIdList = new ArrayList<>();
            searchResponse.ifPresent(response -> {
                final Terms terms = response.getAggregations().get(fessConfig.getIndexFieldSegment());
                for (final Bucket bucket : terms.getBuckets()) {