Couldn't you do the JDBC Wrapper style interface and have a generic method like:
<T> T unwrap(Class<T> cls); Or make more specific unwrap methods like: <T extends Statement> T unwrap(Class<T> cls); If this is for implementation-specific casts and such. On 12 September 2016 at 19:56, Stian Soiland-Reyes <st...@apache.org> wrote: > [[ Cross-post - prefer replies to dev@commons ]] > > Each of the Common RDF implementations come with a RDFTermFatory > > http://stain.github.io/incubator-commonsrdf/integration/org/apache/ > commons/rdf/api/RDFTermFactory.html > > On a classical flat classloader the implementations of this factory > can be discovered with java.util.ServiceLoader > > > So if you have say a JsonLdRDFTermFactory you can call .createTriple() > etc - and it would be backed by that implementation. As mentioned the > marker interfaces will allow you to later on get hold of the wrapped > object, e.g. to do some RDFS reasoning on a Jena Model or to parse it > to a serializer. > > > But what if you already have a 'native' object, e.g. a > org.eclipse.rdf4j.model.Statement - and you want to convert it/adapt > it to the corresponding Commons RDF API Triple? > > Obviously there would not be a general interface for this (without > using ?-generics) as each backend implementation would have different > (so far unrelated) types - but we can at least agree on the common > style? > > In > > http://stain.github.io/incubator-commonsrdf/integration/org/apache/ > commons/rdf/rdf4j/RDF4JTermFactory.html > > I suggests as*() adapter methods like: > > > RDF4JQuad asQuad(org.eclipse.rdf4j.model.Statement > > RDF4JTriple asTriple(org.eclipse.rdf4j.model.Statement statement) > > RDF4JTerm asRDFTerm(org.eclipse.rdf4j.model.Value value) > > RDF4JDataset asRDFTermDataset(org.eclipse.rdf4j.repository.Repository > repository) > > RDF4JGraph asRDFTermGraph(org.eclipse.rdf4j.model.Model model) > > RDF4JGraph asRDFTermGraph(org.eclipse.rdf4j.repository.Repository > repository) > > > but also the inverse converters: > > org.eclipse.rdf4j.model.Value asValue(RDFTerm term) > > org.eclipse.rdf4j.model.Statement > asStatement(TripleLike<BlankNodeOrIRI,IRI,RDFTerm> tripleLike) > > > (These will unpack the wrapped value if it's an RDF4JTerm - or create > a new RDF4J native instance if it's a "foreign" class) > > > Questions: > > > a) Do these adapter methods belong in the RDFTermFactory or should > there be a new family of 'adaptor factories'? (e.g. the Jena Factory > > > b) What should we call these methods? Is as*() appropriate or should > they more closely match the createTriple() etc methods from > RDFTermFactory? > > With asSomething() I wanted to hint of adaptation - rather than > 'convert' or 'create' - but without having to commit to adaptation > with adapt() or wrap(). > > > Now sometimes the implementations use the same class name as Commons > RDF (e.g. Quad or Graph). Code-wise this is not too hard to deal with > (avoid importing either), but it means it can get more confusing for > downstream API users who do auto-complete and then don't know what > direction they are adapting. > > > c) Should the adapter methods have short names (e.g. asGraph()) - > distinguished by type polymorphism and javadocs - or more verbose to > show which particular return-type you get? (e.g. asJenaGraph() and > asCommonsRDFGraph()) ) > > > d) Do we need to rename RDFTermFactory to RDFFactory (or just RDF) ? > > > > -- > Stian Soiland-Reyes > http://orcid.org/0000-0001-9842-9718 > > --------------------------------------------------------------------- > To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org > For additional commands, e-mail: dev-h...@commons.apache.org > > -- Matt Sicker <boa...@gmail.com>
