split(fessConfig.getSuggestFieldTags(), ",").of(stream -> stream.filter(StringUtil::isNotBlank).forEach(tagFieldNameSet::add));
        split(fessConfig.getSuggestFieldRoles(), ",").of(stream -> stream.filter(StringUtil::isNotBlank).forEach(roleFieldNameSet::add));
        contentFieldList = Arrays.asList(stream(fessConfig.getSuggestFieldContents()).get(stream -> stream.toArray(n -> new String[n])));

     * The value is, e.g. role <br>
     * comment: Field for suggestion roles.
     * @return The value of found property. (NotNull: if not found, exception but basically no way)
     */
    String getSuggestFieldRoles();

    /**
     * Get the value for the key 'suggest.field.index.contents'. <br>
     * The value is, e.g. content,title <br>
     * comment: Index contents for suggestion.