RdfProvides class

Marks a property as providing a named value that can be referenced in IRI templates in the RDF mapping system.

This annotation makes the property's value available to mappers via constructor injection, but only to those that explicitly require the value by name and signature in their constructor. The value can then be referenced in IRI templates using the provided name. This works consistently across all levels:

Property mappers within the same class receive the provided values if their constructor requires a provider for that specific variable
Property mappers for nested resources (child objects) receive the provided values if they require them in their constructor
IRI templates can reference these values using {variableName} and the system automatically ensures the necessary providers are available

Technically, the same constructor injection mechanism is used in all cases - each property mapper receives provider functions for all variables it needs. This avoids the need to register global provider functions in initRdfMapper for values that are available within the object graph.

Alternative: Providing the Resource IRI

Instead of annotating properties with @RdfProvides, you can also provide the resource's own IRI to dependent mappers by using the providedAs parameter on IriStrategy. See IriStrategy documentation for details on this alternative approach.

Examples:

Example: Using @RdfProvides to pass parentId to Iri property and nested resource

@RdfGlobalResource(
  ExampleVocab.Parent,
  IriStrategy('{+baseUri}/{id}.ttl'),
)
class Parent {
  @RdfIriPart()
  @RdfProvides("parentId")
  late String id;

  @RdfProperty(ExampleVocab.child)
  late Child child;

  @RdfProperty(ExampleVocab.sibling,
      iri: IriMapping('{+baseUri}/{parentId}/sibling/{siblingId}.ttl'))
  late String siblingId;
}

@RdfGlobalResource(
  ExampleVocab.Child,
  IriStrategy('{+baseUri}/{parentId}/child/{id}.ttl'),
  registerGlobally: false,
)
class Child {
  @RdfIriPart()
  late String id;

  @RdfProperty(ExampleVocab.childName)
  late String name;
}

Note that the baseUri will be provided by a global provider function in initRdfMapper, while the parentId is provided by the @RdfProvides annotation on the id property of the Parent class. The Child class is annotated to not be registered globally, so it will not be available in initRdfMapper and will only be used within the context of the Parent.

Alternative: Providing the Resource IRI

Constructors

Properties

Methods

Operators

annotations library