}).collect(Collectors.toList()));
    }

    String getIndexAdminDoubleFields();

    default Set<String> getIndexAdminDoubleFieldSet() {
        @SuppressWarnings("unchecked")
        Set<String> fieldSet = (Set<String>) propMap.get(INDEX_ADMIN_DOUBLE_FIELD_SET);
        if (fieldSet == null) {
            fieldSet = split(getIndexAdminDoubleFields(), ",")

     * The value is, e.g.  <br>
     * @return The value of found property. (NotNull: if not found, exception but basically no way)
     */
    String getIndexAdminDoubleFields();

    /**
     * Get the value for the key 'index.admin.double.fields' as {@link Integer}. <br>
     * The value is, e.g.  <br>