String roleFieldName = "role";

    public void test_parseQueryLog() throws Exception {

        QueryLog queryLog = new QueryLog("content:検索エンジン", null);
        List<SuggestItem> items = defaultContentsParser.parseQueryLog(queryLog, supportedFields, tagFieldNames, roleFieldName,
                createDefaultReadingConverter(), createDefaultNormalizer());
        SuggestItem item = items.get(0);
        assertEquals("検索エンジン", item.getText());

     * @param normalizer the normalizer to use for normalizing values
     * @return a list of suggest items parsed from the query log
     */
    List<SuggestItem> parseQueryLog(QueryLog queryLog, String[] fields, String[] tagFieldNames, String roleFieldName,
            ReadingConverter readingConverter, Normalizer normalizer);

    /**

        } catch (final IOException e) {
            throw new SuggesterException("Failed to create SuggestItem from search words.", e);
        }
    }

    @Override
    public List<SuggestItem> parseQueryLog(final QueryLog queryLog, final String[] fields, final String[] tagFieldNames,
            final String roleFieldName, final ReadingConverter readingConverter, final Normalizer normalizer) {

            if (parallel) {
                stream.parallel();
            }
            final SuggestItem[] array = stream.flatMap(queryLog -> contentsParser
                    .parseQueryLog(queryLog, supportedFields, tagFieldNames, roleFieldName, readingConverter, normalizer)
                    .stream()).toArray(n -> new SuggestItem[n]);
            final long parseTime = System.currentTimeMillis();