| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package example; |
| |
| import java.nio.charset.StandardCharsets; |
| import java.nio.file.Files; |
| import java.nio.file.Path; |
| import java.util.Optional; |
| import java.util.stream.Collectors; |
| import java.util.stream.Stream; |
| |
| import org.apache.commons.rdf.api.BlankNode; |
| import org.apache.commons.rdf.api.BlankNodeOrIRI; |
| import org.apache.commons.rdf.api.Graph; |
| import org.apache.commons.rdf.api.IRI; |
| import org.apache.commons.rdf.api.Literal; |
| import org.apache.commons.rdf.api.Quad; |
| import org.apache.commons.rdf.api.QuadLike; |
| import org.apache.commons.rdf.api.RDFTerm; |
| import org.apache.commons.rdf.api.RDF; |
| import org.apache.commons.rdf.api.Triple; |
| import org.apache.commons.rdf.api.TripleLike; |
| import org.apache.commons.rdf.simple.SimpleRDF; |
| import org.apache.commons.rdf.simple.Types; |
| import org.junit.Before; |
| import org.junit.Test; |
| |
| public class UserGuideTest { |
| |
| private RDF factory; |
| |
| @Before |
| public void factory() { |
| factory = new SimpleRDF(); |
| } |
| |
| @Test |
| public void creating() throws Exception { |
| BlankNode aliceBlankNode = factory.createBlankNode(); |
| IRI nameIri = factory.createIRI("http://example.com/name"); |
| Literal aliceLiteral = factory.createLiteral("Alice"); |
| Triple triple = factory.createTriple(aliceBlankNode, nameIri, aliceLiteral); |
| |
| System.out.println(aliceBlankNode.ntriplesString()); |
| System.out.println(nameIri.ntriplesString()); |
| System.out.println(aliceLiteral.ntriplesString()); |
| |
| } |
| |
| @Test |
| public void ntriples() throws Exception { |
| IRI iri = factory.createIRI("http://example.com/alice"); |
| System.out.println(iri.getIRIString()); |
| |
| IRI iri2 = factory.createIRI("http://example.com/alice"); |
| System.out.println(iri.equals(iri2)); |
| |
| IRI iri3 = factory.createIRI("http://example.com/alice/./"); |
| System.out.println(iri.equals(iri3)); |
| |
| System.out.println(iri.equals("http://example.com/alice")); |
| System.out.println(iri.equals(factory.createLiteral("http://example.com/alice"))); |
| |
| } |
| |
| @Test |
| public void blanknode() throws Exception { |
| BlankNode bnode = factory.createBlankNode(); |
| System.out.println(bnode.equals(bnode)); |
| System.out.println(bnode.equals(factory.createBlankNode())); |
| |
| BlankNode b1 = factory.createBlankNode("b1"); |
| |
| System.out.println(b1.ntriplesString()); |
| |
| System.out.println(b1.equals(factory.createBlankNode("b1"))); |
| System.out.println(b1.equals(new SimpleRDF().createBlankNode("b1"))); |
| |
| System.out.println(bnode.uniqueReference()); |
| } |
| |
| @Test |
| public void literal() throws Exception { |
| Literal literal = factory.createLiteral("Hello world!"); |
| System.out.println(literal.ntriplesString()); |
| |
| String lexical = literal.getLexicalForm(); |
| System.out.println(lexical); |
| |
| IRI datatype = literal.getDatatype(); |
| System.out.println(datatype.ntriplesString()); |
| |
| IRI xsdDouble = factory.createIRI("http://www.w3.org/2001/XMLSchema#double"); |
| Literal literalDouble = factory.createLiteral("13.37", xsdDouble); |
| System.out.println(literalDouble.ntriplesString()); |
| |
| Literal literalDouble2 = factory.createLiteral("13.37", Types.XSD_DOUBLE); |
| |
| System.out.println(Types.XSD_STRING.equals(literal.getDatatype())); |
| |
| Literal inSpanish = factory.createLiteral("¡Hola, Mundo!", "es"); |
| System.out.println(inSpanish.ntriplesString()); |
| System.out.println(inSpanish.getLexicalForm()); |
| System.out.println(inSpanish.getDatatype().ntriplesString()); |
| |
| Optional<String> tag = inSpanish.getLanguageTag(); |
| if (tag.isPresent()) { |
| System.out.println(tag.get()); |
| } |
| |
| System.out.println(literal.getLanguageTag().isPresent()); |
| System.out.println(literalDouble.getLanguageTag().isPresent()); |
| } |
| |
| @Test |
| public void triple() throws Exception { |
| BlankNodeOrIRI subject = factory.createBlankNode(); |
| IRI predicate = factory.createIRI("http://example.com/says"); |
| RDFTerm object = factory.createLiteral("Hello"); |
| Triple triple = factory.createTriple(subject, predicate, object); |
| |
| BlankNodeOrIRI subj = triple.getSubject(); |
| System.out.println(subj.ntriplesString()); |
| |
| IRI pred = triple.getPredicate(); |
| System.out.println(pred.getIRIString()); |
| |
| RDFTerm obj = triple.getObject(); |
| System.out.println(obj.ntriplesString()); |
| |
| if (subj instanceof IRI) { |
| String s = ((IRI) subj).getIRIString(); |
| System.out.println(s); |
| } |
| // .. |
| if (obj instanceof Literal) { |
| IRI type = ((Literal) obj).getDatatype(); |
| System.out.println(type); |
| } |
| |
| // Equal triples must have same s,p,o |
| System.out.println(triple.equals(factory.createTriple(subj, pred, obj))); |
| } |
| |
| @Test |
| public void quad() throws Exception { |
| BlankNodeOrIRI graph = factory.createIRI("http://example.com/graph"); |
| BlankNodeOrIRI subject = factory.createBlankNode(); |
| IRI predicate = factory.createIRI("http://example.com/says"); |
| RDFTerm object = factory.createLiteral("Hello"); |
| Quad quad = factory.createQuad(graph, subject, predicate, object); |
| |
| Optional<BlankNodeOrIRI> g = quad.getGraphName(); |
| if (g.isPresent()) { |
| System.out.println(g.get().ntriplesString()); |
| } |
| |
| BlankNodeOrIRI subj = quad.getSubject(); |
| System.out.println(subj.ntriplesString()); |
| |
| // null means default graph |
| Quad otherQuad = factory.createQuad(null, subject, predicate, object); |
| // Equal quads must have same g,s,p,o |
| System.out.println(quad.equals(otherQuad)); |
| |
| // all quads can be viewed as triples - "stripping" the graph |
| Triple asTriple = quad.asTriple(); |
| Triple otherAsTriple = quad.asTriple(); |
| System.out.println(asTriple.equals(otherAsTriple)); |
| |
| // NOTE: Quad does NOT extend Triple, however both Triple and Quad |
| // extend TripleLike |
| |
| TripleLike a = quad; |
| TripleLike b = quad.asTriple(); |
| // Unlike Triple and Quad, TripleLike does not mandate any .equals(), |
| // it just provides common access to getSubject(), getPredicate(), |
| // getObject() |
| |
| // TripleLike supports generalized RDF - therefore all s/p/o are of type |
| // RDFTerm |
| RDFTerm s = a.getSubject(); |
| } |
| |
| @Test |
| public void graph() throws Exception { |
| IRI nameIri = factory.createIRI("http://example.com/name"); |
| BlankNode aliceBlankNode = factory.createBlankNode(); |
| Literal aliceLiteral = factory.createLiteral("Alice"); |
| Triple triple = factory.createTriple(aliceBlankNode, nameIri, aliceLiteral); |
| |
| Graph graph = factory.createGraph(); |
| |
| graph.add(triple); |
| |
| IRI bob = factory.createIRI("http://example.com/bob"); |
| Literal bobName = factory.createLiteral("Bob"); |
| graph.add(bob, nameIri, bobName); |
| |
| System.out.println(graph.contains(triple)); |
| |
| System.out.println(graph.contains(null, nameIri, bobName)); |
| |
| System.out.println(graph.size()); |
| |
| for (Triple t : graph.iterate()) { |
| System.out.println(t.getObject()); |
| } |
| |
| for (Triple t : graph.iterate(null, null, bobName)) { |
| System.out.println(t.getPredicate()); |
| } |
| |
| try (Stream<? extends Triple> triples = graph.stream()) { |
| Stream<RDFTerm> subjects = triples.map(t -> t.getObject()); |
| String s = subjects.map(RDFTerm::ntriplesString).collect(Collectors.joining(" ")); |
| System.out.println(s); |
| } |
| |
| try (Stream<? extends Triple> named = graph.stream(null, nameIri, null)) { |
| Stream<? extends Triple> namedB = named.filter(t -> t.getObject().ntriplesString().contains("B")); |
| System.out.println(namedB.map(t -> t.getSubject()).findAny().get()); |
| } |
| |
| graph.remove(triple); |
| System.out.println(graph.contains(triple)); |
| |
| graph.remove(null, nameIri, null); |
| |
| graph.clear(); |
| System.out.println(graph.contains(null, null, null)); |
| |
| } |
| |
| public static String tripleAsString(Triple t) { |
| return t.getSubject().ntriplesString() + " " + t.getPredicate().ntriplesString() + " " |
| + t.getObject().ntriplesString() + " ."; |
| } |
| |
| public static void writeGraph(Graph graph, Path graphFile) throws Exception { |
| Stream<CharSequence> stream = graph.stream().map(UserGuideTest::tripleAsString); |
| Files.write(graphFile, stream::iterator, StandardCharsets.UTF_8); |
| } |
| } |