org.nuxeo.ecm.platform.semanticentities.service
Class RemoteEntityServiceImpl

java.lang.Object
  org.nuxeo.runtime.model.DefaultComponent
      org.nuxeo.ecm.platform.semanticentities.service.RemoteEntityServiceImpl

All Implemented Interfaces:

RemoteEntityService, RemoteEntitySource, Adaptable, Component, Extensible, TimestampedService

public class RemoteEntityServiceImpl
extends DefaultComponent
implements RemoteEntityService

Default implementation for the RemoteEntityService component. Can be used to register remote entity sources for linked data dereferencing.

Field Summary

static String

REMOTESOURCES_XP_NAME

Constructor Summary

RemoteEntityServiceImpl()

Method Summary

boolean	canDereference(URI remoteEntity)
boolean	canSuggestRemoteEntity()
boolean	dereferenceInto(DocumentModel localEntity, URI remoteEntity, boolean override, boolean lazyResourceFetch) Dereference a remote entity into an existing document model.
boolean	dereferenceIntoFromModel(DocumentModel localEntity, URI remoteEntity, com.hp.hpl.jena.rdf.model.Model rdfModel, boolean override, boolean lazyResourceFetch) Dereference a remote entity into an existing document model from a pre-fetched RDF description of the entity.
Set<String>	getAdmissibleTypes(URI remoteEntity) Introspect the referenced entity to suggest which Nuxeo types can be used to dereference this entity.
void	registerExtension(Extension extension) Registers the given extension.
void	removeSameAsLink(DocumentModel doc, URI uriToRemove) Helper API to unlink a local entity from a remote entity identified by it's URI.
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.
void	unregisterExtension(Extension extension) Unregisters the given extension.

Methods inherited from class org.nuxeo.runtime.model.DefaultComponent

activate, applicationStarted, deactivate, getAdapter, getApplicationStartedOrder, getLastModified, registerContribution, setLastModified, unregisterContribution

Methods inherited from class java.lang.Object

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

Field Detail

REMOTESOURCES_XP_NAME

public static final String REMOTESOURCES_XP_NAME

See Also:

Constant Field Values

Constructor Detail

RemoteEntityServiceImpl

public RemoteEntityServiceImpl()

Method Detail

registerExtension

public void registerExtension(Extension extension)
                       throws Exception

Description copied from interface: Extensible

Registers the given extension.

Specified by:

registerExtension in interface Extensible

Overrides:

registerExtension in class DefaultComponent

Parameters:

extension - the extension to register

Throws:

Exception - if any error occurs

unregisterExtension

public void unregisterExtension(Extension extension)
                         throws Exception

Description copied from interface: Extensible

Unregisters the given extension.

Specified by:

unregisterExtension in interface Extensible

Overrides:

unregisterExtension in class DefaultComponent

Parameters:

extension - the extension to unregister

Throws:

Exception - if any error occurs

canSuggestRemoteEntity

public boolean canSuggestRemoteEntity()

Specified by:

canSuggestRemoteEntity in interface RemoteEntitySource

Returns:

true if the features suggestions by name (a.k.a. entity label)

canDereference

public boolean canDereference(URI remoteEntity)

Specified by:

canDereference in interface RemoteEntitySource

Returns:

true if one of the registered remote sources can handle the provided URI

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.

Specified by:

dereferenceInto in interface RemoteEntitySource

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

dereferenceIntoFromModel

public boolean dereferenceIntoFromModel(DocumentModel localEntity,
                                        URI remoteEntity,
                                        com.hp.hpl.jena.rdf.model.Model rdfModel,
                                        boolean override,
                                        boolean lazyResourceFetch)
                                 throws DereferencingException

Description copied from interface: RemoteEntitySource

Dereference a remote entity into an existing document model from a pre-fetched RDF description of the entity. Only non empty local fields are updated, unless override is set to true. This is typically useful for the SemanticAnalysisService that might receive pre-fetched entity link suggestion and description from the enhancement engines. It is the responsibility of the method caller to save the updated document model back to the repository.

Specified by:

dereferenceIntoFromModel in interface RemoteEntitySource

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

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. This implementation aggregates all the suggestions of the sources that can perform suggestions. Hence the number of aggregate suggestions might be larger than maxSuggestions

Specified by:

suggestRemoteEntity in interface RemoteEntitySource

Throws:

IOException

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).

Specified by:

getAdmissibleTypes in interface RemoteEntitySource

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

removeSameAsLink

public void removeSameAsLink(DocumentModel doc,
                             URI uriToRemove)
                      throws ClientException

Description copied from interface: RemoteEntityService

Helper API to unlink a local entity from a remote entity identified by it's URI. It is the responsability of the caller to save the change in back to the repository if persistence is required.

Specified by:

removeSameAsLink in interface RemoteEntityService

Throws:

ClientException