= Metadata SPI

:Notice: Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file distributed with this work for additional information regarding copyright ownership. The ASF licenses this file to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at. http://www.apache.org/licenses/LICENSE-2.0 . Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR  CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.
:page-partial:


The metadata SPIs allow the framework to obtain metadata from alternative locations.


.Metadata SPIs
[cols="2m,4a",options="header"]
|===

|API
|Description




|xref:refguide:applib:index/services/grid/GridLoaderService.adoc[GridLoaderService]
|Responsible for loading a grid layout for a domain class, eg from a `layout.xml` file.


|xref:refguide:applib:index/services/grid/GridService.adoc[GridService]
|A facade on top of both xref:refguide:applib:index/services/grid/GridLoaderService.adoc[GridLoaderService] and
xref:refguide:applib:index/services/grid/GridSystemService.adoc[GridSystemService], thus being able to return normalized grids for any domain class.



|xref:refguide:applib:index/services/grid/GridSystemService.adoc[GridSystemService]
|Validates and normalizes the grid layout for a domain class (with respect to a particular grid system such as Bootstrap3), also providing a default grid (for those domain classes where there is no grid layout).



|xref:refguide:applib:index/services/menu/MenuBarsLoaderService.adoc[MenuBarsLoaderService]
|Low-level SPI to load the serialized form of the menubars (normally: the `menubars.layout.xml`) into memory.
Used by


|xref:refguide:applib:index/services/menu/MenuBarsService.adoc[MenuBarsService]
|Constructs and normalizes the in-memory representation of the menubars.


|xref:refguide:applib:index/services/i18n/TranslationsResolver.adoc[TranslationsResolver]
|Obtain translations for a particuar phrase and locale, in support of i18n (ie so that the app's UI, messages and exceptions can be translated to the required locale by the xref:refguide:applib:index/services/i18n/TranslationService.adoc[TranslationService]



|===



