org.nuxeo.ecm.platform.semanticentities.sources

Class DBpediaEntitySource

java.lang.Object

org.nuxeo.ecm.platform.semanticentities.service.ParameterizedHTTPEntitySource

org.nuxeo.ecm.platform.semanticentities.sources.DBpediaEntitySource

All Implemented Interfaces:

RemoteEntitySource

public class DBpediaEntitySource
extends ParameterizedHTTPEntitySource

Implementation of the RemoteEntitySource interface that is able to suggest DBpedia entities by name using the http://lookup.dbpedia.org RESTful service and dereference DBpedia URIs using the official DBpedia sparql endpoint. This implementation uses the SPARQL endpoint instead of HTTP GET based queries since the virtuoso implementation arbitrarily truncates the entity graph to around 2000 triples for entities with many properties.

Field Summary

Fields inherited from class org.nuxeo.ecm.platform.semanticentities.service.ParameterizedHTTPEntitySource

OWL_THING, RDF_TYPE

Constructor Summary

Constructors

Constructor and Description
DBpediaEntitySource()

Method Summary

Methods

Modifier and Type	Method and Description
boolean	dereferenceInto(DocumentModel localEntity, URI remoteEntity, boolean override, boolean lazyResourceFetch) Dereference a remote entity into an existing document model.
Set<String>	getAdmissibleTypes(URI remoteEntity) Introspect the referenced entity to suggest which Nuxeo types can be used to dereference this entity.
List<EntitySuggestion>	suggestRemoteEntity(String keywords, String type, int maxSuggestions) Perform query on registered remote entity sources to suggests entity definitions that match the name given as keywords and the requested entity type.

Methods inherited from class org.nuxeo.ecm.platform.semanticentities.service.ParameterizedHTTPEntitySource

canDereference, canSuggestRemoteEntity, dereferenceIntoFromModel, setDescriptor

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

DBpediaEntitySource

public DBpediaEntitySource()

Method Detail

getAdmissibleTypes

public Set<String> getAdmissibleTypes(URI remoteEntity)
                               throws DereferencingException

Description copied from interface: RemoteEntitySource

Introspect the referenced entity to suggest which Nuxeo types can be used to dereference this entity. The first element of the list should be the type the user should expect in front facing label (e.g. the most specific). Hence the set implementation should imply unicity as all set but also preserver ordering (e.g. a LinkedHashSet for instance).

Parameters:

remoteEntity - the URI of the entity to dereference

Returns:

an ordered set of Nuxeo Core type names that can be used to dereference the entity into a local copy

Throws:

DereferencingException

dereferenceInto

public boolean dereferenceInto(DocumentModel localEntity,
                      URI remoteEntity,
                      boolean override,
                      boolean lazyResourceFetch)
                        throws DereferencingException

Description copied from interface: RemoteEntitySource

Dereference a remote entity into an existing document model. Only non empty local fields are updated, unless override is set to true. It is the responsibility of the method caller to save the updated document model back to the repository.

Parameters:

localEntity - local document model to store a copy of the entity attribute

remoteEntity - the URI of the entity to dereference

override - replace non-empty local fields with values from the remote entity

lazyResourceFetch - if true, delay the fetch of the content of referenced resources (e.g. JPEG images) to first access.

Returns:

true if a suitable remote entity description was found in the source, false otherwise.

Throws:

DereferencingException

suggestRemoteEntity

public List<EntitySuggestion> suggestRemoteEntity(String keywords,
                                         String type,
                                         int maxSuggestions)
                                           throws IOException

Description copied from interface: RemoteEntitySource

Perform query on registered remote entity sources to suggests entity definitions that match the name given as keywords and the requested entity type. The caller will then typically ask the user to select one of the suggestions and then dereference of the remote entity into a local copy for easy off-line reuse and indexing in the local repository. The suggestion backend should order the results by a mix of keyword relevance and popularity.

Throws:

IOException