How can I parse Annotations with Olingo?

Question

My Java application uses SAP's repackaged Olingo library for v2 OData services, https://mvnrepository.com/artifact/com.sap.cds.repackaged/odata-v2-lib, to parse the metadata.xml document of an OData service:

Edm parsedMetadata = EntityProvider.readMetadata(inputStream, true);

I do this to analyze the available entities and associations, and it works fine. However, the metadata document also contains <Annotations> that I am interested in:

<?xml version="1.0" encoding="utf-8"?>
<edmx:Edmx ...>
    <edmx:Reference ... /></edmx:Reference>
    <edmx:DataServices ...>
        <Schema ...>
            <EntityType .../>
            ...
            <ComplexType ...>...</ComplexType>
            ...
            <Association ...>...</Association>
            ...
            <Annotations ...>...</Annotations>     <!-- I want these here -->
            ...
        </Schema>
    </edmx:DataServices>
</edmx:Edmx>

Olingo's Edm object provides all sorts of getters for the different parts, like entity types, complex types, and associations, but none for annotations. I also didn't find any other classes in Olingo that would support me in retrieving them.

Is there a possibility to get these Annotations details via Olingo, too? If not, are there other possibilities how I could get these?

Answer 1

They are available at the EntityContainer level

You can retieve them like this

Edm parsedMetadata = EntityProvider.readMetadata(con.getInputStream(), true);

EdmAnnotations annotations = parsedMetadata.getDefaultEntityContainer().getAnnotations();

Or if you have multiple containers or want to use the named API it would be

EdmAnnotations annotations = parsedMetadata.getEntityContainer("SomeName").getAnnotations();

Otherwise on all the properties there is a getAnnotations method but then you'll have to loop over all the properties and consolidate the annotations

For example

for (EdmEntitySet e : parsedMetadata.getEntitySets() ){
        EdmAnnotations annotations = e.getAnnotations();
}