本文整理了Java中org.apache.commons.rdf.api.Graph.stream()方法的一些代码示例，展示了Graph.stream()的具体用法。这些代码示例主要来源于Github/Stackoverflow/Maven等平台，是从一些精选项目中提取出来的代码，具有较强的参考意义，能在一定程度帮忙到你。Graph.stream()方法的具体详情如下：
包路径：org.apache.commons.rdf.api.Graph
类名称：Graph
方法名：stream

Graph.stream介绍

[英]Gets all triples contained by the graph.

The iteration does not contain any duplicate triples, as determined by the Triple#equals(Object) method for each Triple.

The behaviour of the Stream is not specified if #add(Triple), #remove(Triple) or #clear() are called on the Graph before it terminates.

Implementations may throw ConcurrentModificationException from Stream methods if they detect a conflict while the Stream is active.
[中]获取图形包含的所有三元组。
迭代不包含任何重复的三元组，由每个三元组的Triple#equals（Object）方法确定。
如果在图形终止之前对其调用#add（Triple）、#remove（Triple）或#clear（），则不会指定流的行为。
如果流方法在流处于活动状态时检测到冲突，则实现可能会从流方法中抛出ConcurrentModificationException。

代码示例

代码示例来源：origin: trellis-ldp/trellis

/**
 * Stream triples from the graph.
 *
 * @return a stream of triples
 */
public Stream<Triple> stream() {
  return graph.stream().map(Triple.class::cast);
}

代码示例来源：origin: org.apache.commons/commons-rdf-api

/**
 * This method is deprecated, use the equivalent method {@link #stream()}
 * instead.
 *
 * @return A {@link Stream} over all triples.
 */
@Deprecated
default Stream<? extends Triple> getTriples() {
  return stream();
}

代码示例来源：origin: org.trellisldp/trellis-constraint-rules

private static boolean hasMembershipProps(final Graph graph) {
  return graph.contains(null, LDP.membershipResource, null)
      && (graph.stream(null, LDP.hasMemberRelation, null).count()
        + graph.stream(null, LDP.isMemberOfRelation, null).count() == 1L);
}

代码示例来源：origin: trellis-ldp/trellis

private static boolean hasMembershipProps(final Graph graph) {
  return graph.contains(null, LDP.membershipResource, null)
      && (graph.stream(null, LDP.hasMemberRelation, null).count()
        + graph.stream(null, LDP.isMemberOfRelation, null).count() == 1L);
}

代码示例来源：origin: eu.optique-project/r2rml-api-core

/**
 * This method processes the given Resource node as subject by finding the
 * object node with the given resourceType URI as predicate. Finds and
 * returns the first object.
 * 
 * @param node
 *            The Resource node as subject
 * @param resourceType
 *            The URI as predicate
 * @return the extracted first object as String
 */
private Collection<RDFTerm> readObjectsInMappingGraph(BlankNodeOrIRI node, IRI resourceType) {
  // look for resourceType declaration
  return graph.stream(node, resourceType, null)
      .map(Triple::getObject)
      .collect(toSet());
}

代码示例来源：origin: org.trellisldp/trellis-rosid-common

@Override
public Collection<IRI> getAgents() {
  return data.getGraph(Trellis.PreferAudit)
    .map(graph -> graph.stream(null, PROV.wasAssociatedWith, null).map(Triple::getObject)
        .filter(term -> term instanceof IRI).map(term -> (IRI) term).collect(toList()))
    .orElseGet(Collections::emptyList);
}

代码示例来源：origin: org.trellisldp/trellis-rosid-common

@Override
public Collection<IRI> getTypes() {
  return data.getGraph(Trellis.PreferAudit)
    .map(graph -> graph.stream(null, type, null).map(Triple::getObject)
        .filter(term -> term instanceof IRI).map(term -> (IRI) term).collect(toList()))
    .orElseGet(Collections::emptyList);
}

代码示例来源：origin: org.trellisldp/trellis-rosid-common

@Override
  public Optional<IRI> getInbox() {
    return data.getGraph(Trellis.PreferUserManaged)
      .flatMap(graph -> graph.stream(null, LDP.inbox, null).map(Triple::getObject)
          .filter(term -> term instanceof IRI).map(term -> (IRI) term).findFirst());
  }
}

代码示例来源：origin: trellis-ldp/trellis

@Override
  public Stream<ConstraintViolation> constrainedBy(final IRI model, final Graph graph, final String domain) {
    return concat(graph.stream().flatMap(checkModelConstraints(model, domain)),
        Stream.of(graph).filter(checkCardinality(model))
          .map(g -> new ConstraintViolation(Trellis.InvalidCardinality, g.stream().collect(toList()))));
  }
}

代码示例来源：origin: org.trellisldp/trellis-constraint-rules

@Override
  public Stream<ConstraintViolation> constrainedBy(final IRI model, final Graph graph, final String domain) {
    return concat(graph.stream().flatMap(checkModelConstraints(model, domain)),
        Stream.of(graph).filter(checkCardinality(model))
          .map(g -> new ConstraintViolation(Trellis.InvalidCardinality, g.stream().collect(toList()))));
  }
}

代码示例来源：origin: trellis-ldp/trellis

protected Metadata.Builder metadataBuilder(final IRI identifier, final IRI ixnModel, final TrellisDataset mutable) {
  final Metadata.Builder builder = Metadata.builder(identifier).interactionModel(ixnModel);
  mutable.asDataset().getGraph(Trellis.PreferUserManaged).ifPresent(graph -> {
    graph.stream(identifier, LDP.membershipResource, null).findFirst().map(Triple::getObject)
      .filter(IRI.class::isInstance).map(IRI.class::cast).ifPresent(builder::membershipResource);
    graph.stream(identifier, LDP.hasMemberRelation, null).findFirst().map(Triple::getObject)
      .filter(IRI.class::isInstance).map(IRI.class::cast).ifPresent(builder::memberRelation);
    graph.stream(identifier, LDP.isMemberOfRelation, null).findFirst().map(Triple::getObject)
      .filter(IRI.class::isInstance).map(IRI.class::cast).ifPresent(builder::memberOfRelation);
    graph.stream(identifier, LDP.insertedContentRelation, null).findFirst().map(Triple::getObject)
      .filter(IRI.class::isInstance).map(IRI.class::cast).ifPresent(builder::insertedContentRelation);
  });
  return builder;
}

代码示例来源：origin: trellis-ldp/trellis

private List<Authorization> getAuthorizationFromGraph(final Graph graph) {
  return graph.stream().map(Triple::getSubject).distinct().map(subject -> {
      try (final WrappedGraph subGraph = wrap(graph.stream(subject, null, null).collect(toGraph()))) {
        return Authorization.from(subject, subGraph.getGraph());
      }
    }).collect(toList());
}

代码示例来源：origin: org.trellisldp/trellis-constraint-rules

private static Predicate<Graph> checkCardinality(final IRI model) {
  return graph -> {
    if (LDP.IndirectContainer.equals(model)) {
      if (!graph.contains(null, LDP.insertedContentRelation, null) || !hasMembershipProps(graph)) {
        return true;
      }
    } else if (LDP.DirectContainer.equals(model) && !hasMembershipProps(graph)) {
      return true;
    }
    return propertiesWithUriRange.stream().anyMatch(p -> graph.stream(null, p, null).count() > 1);
  };
}

代码示例来源：origin: trellis-ldp/trellis

private static Predicate<Graph> checkCardinality(final IRI model) {
  return graph -> {
    if (LDP.IndirectContainer.equals(model)) {
      if (!graph.contains(null, LDP.insertedContentRelation, null) || !hasMembershipProps(graph)) {
        return true;
      }
    } else if (LDP.DirectContainer.equals(model) && !hasMembershipProps(graph)) {
      return true;
    }
    return propertiesWithUriRange.stream().anyMatch(p -> graph.stream(null, p, null).count() > 1);
  };
}

代码示例来源：origin: org.apache.commons/commons-rdf-jena

/**
 * Convert a CommonsRDF Graph to a Jena Graph. If the Graph was from Jena
 * originally, return that original object else create a copy using Jena
 * objects.
 *
 * @param graph
 *            Commons RDF {@link Graph} to convert
 * @return Converted Jena {@link org.apache.jena.graph.Graph}
 */
public org.apache.jena.graph.Graph asJenaGraph(final Graph graph) {
  if (graph instanceof JenaGraph) {
    return ((JenaGraph) graph).asJenaGraph();
  }
  final org.apache.jena.graph.Graph g = GraphFactory.createGraphMem();
  graph.stream().forEach(t -> g.add(asJenaTriple(t)));
  return g;
}

代码示例来源：origin: org.apache.commons/commons-rdf-api

@Test
public void stream() throws Exception {
  assertEquals(new DummyTriple(), graph.stream().findAny().get());
}

代码示例来源：origin: org.trellisldp/trellis-triplestore

@Override
public CompletionStage<Void> add(final IRI id, final Dataset dataset) {
  return runAsync(() -> {
    final IRI graphName = rdf.createIRI(id.getIRIString() + "?ext=audit");
    try (final Dataset data = rdf.createDataset()) {
      dataset.getGraph(PreferAudit).ifPresent(g ->
          g.stream().forEach(t -> data.add(graphName, t.getSubject(), t.getPredicate(), t.getObject())));
      executeWrite(rdfConnection, () -> rdfConnection.loadDataset(asJenaDataset(data)));
    } catch (final Exception ex) {
      throw new RuntimeTrellisException("Error storing audit dataset for " + id, ex);
    }
  });
}

代码示例来源：origin: trellis-ldp/trellis

@Override
public CompletionStage<Void> add(final IRI id, final Dataset dataset) {
  return runAsync(() -> {
    final IRI graphName = rdf.createIRI(id.getIRIString() + "?ext=audit");
    try (final Dataset data = rdf.createDataset()) {
      dataset.getGraph(PreferAudit).ifPresent(g ->
          g.stream().forEach(t -> data.add(graphName, t.getSubject(), t.getPredicate(), t.getObject())));
      executeWrite(rdfConnection, () -> rdfConnection.loadDataset(asJenaDataset(data)));
    } catch (final Exception ex) {
      throw new RuntimeTrellisException("Error storing audit dataset for " + id, ex);
    }
  });
}

代码示例来源：origin: org.apache.commons/commons-rdf-api

@Test
public void streamFiltered() throws Exception {
  assertEquals(new DummyTriple(), graph.stream(null, null, null).findAny().get());
  assertEquals(new DummyTriple(),
      graph.stream(new DummyIRI(1), new DummyIRI(2), new DummyIRI(3)).findAny().get());
  assertFalse(graph.stream(new DummyIRI(0), new DummyIRI(0), new DummyIRI(0)).findAny().isPresent());
}

代码示例来源：origin: org.apache.commons/commons-rdf-api

@Test
public void getTriples() throws Exception {
  long tripleCount;
  try (Stream<? extends Triple> stream = graph.stream()) {
    tripleCount = stream.count();
  }
  assertTrue(tripleCount > 0);
  try (Stream<? extends Triple> stream = graph.stream()) {
    assertTrue(stream.allMatch(t -> graph.contains(t)));
  }
  // Check exact count
  Assume.assumeNotNull(bnode1, bnode2, aliceName, bobName, secretClubName, companyName, bobNameTriple);
  assertEquals(8, tripleCount);
}