org.trellisldp.api

Interface ResourceService

All Superinterfaces:

RetrievalService<Resource>

All Known Implementing Classes:

InMemoryResourceService, NoopResourceService, TriplestoreResourceService

public interface ResourceService
extends RetrievalService<Resource>

The ResourceService provides methods for creating, retrieving and manipulating Trellis resources.

Implementation Requirements:

Implementations should take care to provide any initialization needed, in a constructor or methods managed by an external framework (e.g. using PostConstruct). This may or may not include actions in external systems like databases, which may be better managed elsewhere.

Method Summary

Modifier and Type	Method and Description
CompletionStage<Void>	add(IRI identifier, Dataset dataset)
default CompletionStage<Void>	create(Metadata metadata, Dataset dataset) Create a resource in the server.
CompletionStage<Void>	delete(Metadata metadata) Delete a resource from the server.
String	generateIdentifier() An identifier generator.
CompletionStage<Void>	replace(Metadata metadata, Dataset dataset) Replace a resource in the server.
default RDFTerm	skolemize(RDFTerm term) Skolemize a blank node.
Set<IRI>	supportedInteractionModels() Return a collection of interaction models supported by this Resource Service.
default <T extends RDFTerm> T	toExternal(T term, String baseUrl) Return an "external" representation of an RDF term.
default <T extends RDFTerm> T	toInternal(T term, String baseUrl) Return an "internal" representation of an RDF term.
CompletionStage<Void>	touch(IRI identifier) Update the modification date of the provided resource.
default RDFTerm	unskolemize(RDFTerm term) Un-skolemize a blank node.

Methods inherited from interface org.trellisldp.api.RetrievalService

get

Method Detail

create

default CompletionStage<Void> create(Metadata metadata,
                                     Dataset dataset)

Create a resource in the server.

Parameters:

metadata - metadata for the new resource

dataset - the dataset to be persisted

Returns:

a new completion stage that, when the stage completes normally, indicates that the supplied data were successfully created in the corresponding persistence layer. In the case of an unsuccessful write operation, the CompletionStage will complete exceptionally and can be handled with CompletionStage.handle(java.util.function.BiFunction<? super T, java.lang.Throwable, ? extends U>), CompletionStage.exceptionally(java.util.function.Function<java.lang.Throwable, ? extends T>) or similar methods.

Implementation Requirements:

the default implementation of this method is to proxy create requests to the replace(org.trellisldp.api.Metadata, org.apache.commons.rdf.api.Dataset) method.

replace

CompletionStage<Void> replace(Metadata metadata,
                              Dataset dataset)

Replace a resource in the server.

Parameters:

metadata - metadata for the resource

dataset - the dataset to be persisted

Returns:

a new completion stage that, when the stage completes normally, indicates that the supplied data were successfully stored in the corresponding persistence layer. In the case of an unsuccessful write operation, the CompletionStage will complete exceptionally and can be handled with CompletionStage.handle(java.util.function.BiFunction<? super T, java.lang.Throwable, ? extends U>), CompletionStage.exceptionally(java.util.function.Function<java.lang.Throwable, ? extends T>) or similar methods.

delete

CompletionStage<Void> delete(Metadata metadata)

Delete a resource from the server.

Parameters:

metadata - metadata for the resource

Returns:

a new completion stage that, when the stage completes normally, indicates that the resource was successfully deleted from the corresponding persistence layer. In the case of an unsuccessful delete operation, the CompletionStage will complete exceptionally and can be handled with CompletionStage.handle(java.util.function.BiFunction<? super T, java.lang.Throwable, ? extends U>), CompletionStage.exceptionally(java.util.function.Function<java.lang.Throwable, ? extends T>) or similar methods.

add

CompletionStage<Void> add(IRI identifier,
                          Dataset dataset)

Parameters:

identifier - the identifier under which to persist a dataset

dataset - a dataset to persist

Returns:

a new completion stage that, when the stage completes normally, indicates that the supplied data were successfully stored in the corresponding persistence layer. In the case of an unsuccessful write operation, the CompletionStage will complete exceptionally and can be handled with CompletionStage.handle(java.util.function.BiFunction<? super T, java.lang.Throwable, ? extends U>), CompletionStage.exceptionally(java.util.function.Function<java.lang.Throwable, ? extends T>) or similar methods.

skolemize

default RDFTerm skolemize(RDFTerm term)

Skolemize a blank node.

Parameters:

term - the RDF term

Returns:

a skolemized node, if a blank node; otherwise the original term

unskolemize

default RDFTerm unskolemize(RDFTerm term)

Un-skolemize a blank node.

Parameters:

term - the RDF term

Returns:

a blank node, if a previously-skolemized node; otherwise the original term

toInternal

default <T extends RDFTerm> T toInternal(T term,
                                         String baseUrl)

Return an "internal" representation of an RDF term.

Type Parameters:

T - the type of RDF term

Parameters:

term - the RDF term

baseUrl - the base URL of the domain

Returns:

the "internal" RDF term

toExternal

default <T extends RDFTerm> T toExternal(T term,
                                         String baseUrl)

Return an "external" representation of an RDF term.

Type Parameters:

T - the type of RDF term

Parameters:

term - the RDF term

baseUrl - the base URL of the domain

Returns:

the "external" RDF term

touch

CompletionStage<Void> touch(IRI identifier)

Update the modification date of the provided resource.

Parameters:

identifier - the identifier of the resource

Returns:

a new completion stage that, when the stage completes normally, indicates that the identified resource has been updated with a new modification date.

API Note:

In general, when this method is called, it can be expected that the target resource will already exist. In cases where that resource does not already exist, an implementation may choose to throw an exception, log an error or simply do nothing.

supportedInteractionModels

Set<IRI> supportedInteractionModels()

Return a collection of interaction models supported by this Resource Service.

Returns:

a set of supported interaction models

generateIdentifier

String generateIdentifier()

An identifier generator.

Returns:

a new identifier