org.aksw.jena_sparql_api.mapper.model

Interface RdfType

All Known Implementing Classes:

RdfClass, RdfTypeBase, RdfTypeCollection, RdfTypeCollectionBase, RdfTypeComplexBase, RdfTypeIriStr, RdfTypeLiteralTyped, RdfTypeMap, RdfTypePrimitiveBase, RdfTypeSeq

public interface RdfType

Base class for operations for mapping java objects of *a specific* class to and from sets of triples.

• fetch data from a remote store
• instanciate a corresponding java class (can be a proxy implementing appropriate interfaces)
• set properties on the instance

Hence, an RDF type exposes information for two phases:

• a shape object that identifies the sub graph relevant for initializing properties
• a function that sets properties on an object from that sub graph
• a function that converts the state of an object to RDF in regard to this class

can expose information for two phases a 'shape' of triples

Author:

raven

Method Summary

Modifier and Type	Method and Description
Object	createJavaObject(org.apache.jena.rdf.model.RDFNode r) Extract a Java (literal) object from a given node.
void	exposeFragment(ResourceFragment out, org.apache.jena.rdf.model.Resource priorState, Object entity)
void	exposeShape(ResourceShapeBuilder rsb)
Class<?>	getEntityClass() Return the Java class corresponding to this type (maybe it should be Type instead of Class)
org.apache.jena.graph.Node	getRootNode(Object obj) Return the root node that corresponds to the given object in regard to this RdfType.
boolean	hasIdentity() Flag to indicate whether entities created from this mapping have their own identity.
boolean	isSimpleType() A simple type is a type that does not need to emit any triples, i.e.
EntityFragment	populate(org.apache.jena.rdf.model.Resource shape, Object entity) Populates an entity from a resource RDF graph that should match the exposed shape.
PathFragment	resolve(String propertyName)

Method Detail

getEntityClass

Class<?> getEntityClass()

Return the Java class corresponding to this type (maybe it should be Type instead of Class)

Returns:

getRootNode

org.apache.jena.graph.Node getRootNode(Object obj)

Return the root node that corresponds to the given object in regard to this RdfType. In the case of classes, this is an IRI node, whereas for literals this is either a plain or typed literal node. Note, that the following condition is expected to hold: getRootNode(createJavaObject(node)).equals(node) For types mapping to plain literals, this method should (must?) never return null. Note that certain Java types may not have capabilities assigned for returning a node for a given object. In this case, the result will be null.

Parameters:

obj -

Returns:

hasIdentity

boolean hasIdentity()

Flag to indicate whether entities created from this mapping have their own identity. If not, ids are usually derived from the parent object

Returns:

createJavaObject

Object createJavaObject(org.apache.jena.rdf.model.RDFNode r)

Extract a Java (literal) object from a given node. Note: Creating a *non-primitive* java object is not a concern of RdfType which only *MAPS* between a java object and its corresponding triples. The reason is, that via the RdfType's entity class the association to a newInstance method can be indirectly made on the outside, without RdfType having to be aware of it. Also, an RdfType reading a collection may be capable of reading and writing to any collection type, regardless of the concrete sub-type (list, set, etc). Create an empty java object (i.e. no properties set) based on the given node. In the case of primitive types (e.g. String, Long, etc), the object will already carry the correct value. In the case of classes, the result may either be a Java object regardless of the node argument, or a proxy to such java object that holds the node

Parameters:

node -

Returns:

isSimpleType

boolean isSimpleType()

A simple type is a type that does not need to emit any triples, i.e. a simple type can de/serialize java objects to and from Node objects.

Returns:

exposeShape

void exposeShape(ResourceShapeBuilder rsb)

exposeFragment

void exposeFragment(ResourceFragment out,
                    org.apache.jena.rdf.model.Resource priorState,
                    Object entity)

Parameters:

out -

priorState -

entity -

populate

EntityFragment populate(org.apache.jena.rdf.model.Resource shape,
                        Object entity)

Populates an entity from a resource RDF graph that should match the exposed shape.

Parameters:

inout -

shape -

entity -

resolve

PathFragment resolve(String propertyName)