How to use

DatasetImpl

in

org.apache.jena.sparql.core

/** Wrap an existing DatasetGraph */
public static Dataset wrap(DatasetGraph datasetGraph) {
  return new DatasetImpl(datasetGraph) ;
}

/**
 * Wrap a {@link DatasetGraph} to make a dataset
 *
 * @param dataset DatasetGraph
 * @return Dataset
 */
public static Dataset wrap(DatasetGraph dataset) {
  Objects.requireNonNull(dataset, "Can't wrap a null DatasetGraph reference") ;
  return DatasetImpl.wrap(dataset);
}

@Override
public Model getNamedModel(String uri) {
  checkGraphName(uri) ;
  Node n = NodeFactory.createURI(uri) ;
  return graph2model(dsg.getGraph(n)) ;
}

@Override
public void abort() {
  checkTransactional();
  transactional.abort();
}

@Override
public boolean containsNamedModel(String uri) {
  // Does not touch the cache.
  checkGraphName(uri) ;
  Node n = NodeFactory.createURI(uri) ;
  return dsg.containsGraph(n) ;
}

private void checkTransactional() {
  if ( ! supportsTransactions() )
    throw new UnsupportedOperationException("Transactions not supported") ;
}

@Override
public void commit() {
  checkTransactional();
  transactional.commit();
}

@Override
public Dataset removeNamedModel(String uri) {
  checkGraphName(uri) ;
  Node n = NodeFactory.createURI(uri) ;
  dsg.removeGraph(n) ;
  return this;
}

public static FluentUpdateExecutionFactory from(DatasetGraph datasetGraph, Context context) {
  Dataset dataset = DatasetImpl.wrap(datasetGraph);
  FluentUpdateExecutionFactory result = from(dataset, context);
  return result;
}

/**
 * Create a dataset, starting with the model argument as the default graph of the
 * dataset. Named graphs can be added. 
 * <p> 
 * Use {@link #wrap(Model)} to put dataset functionality around a single
 * model when named graphs will not be added.
 * 
 * @param model The model for the default graph
 * @return a dataset with the given model as the default graph
 */
public static Dataset create(Model model) {
  Objects.requireNonNull(model, "Default model must be provided") ;
  return new DatasetImpl(model);
}

@Override
public ReadWrite transactionMode() {
  checkTransactional();
  return transactional.transactionMode();
}

@Override
public Dataset addNamedModel(String uri, Model model) {
  checkGraphName(uri) ;
  Node n = NodeFactory.createURI(uri) ;
  dsg.addGraph(n, model.getGraph()) ;
  return this;
}

public static FluentQueryExecutionFactory<?> from(DatasetGraph datasetGraph, Context context) {
  Dataset dataset = DatasetImpl.wrap(datasetGraph);
  return from(dataset, context);
}

/**
 * @param dataset Dataset to clone structure from.
 * @return a dataset: clone the dataset structure of named graphs, and share the graphs themselves.
 * @deprecated This operation may be removed.
 */
@Deprecated
public static Dataset create(Dataset dataset) {
  Objects.requireNonNull(dataset, "Clone dataset is null") ;
  return new DatasetImpl(dataset);
}

@Override
public boolean promote(Promote txnType) {
  checkTransactional();
  return transactional.promote(txnType);
}

@Override
public Dataset replaceNamedModel(String uri, Model model) {
  // Assumes single writer.
  checkGraphName(uri) ;
  Node n = NodeFactory.createURI(uri) ;
  dsg.removeGraph(n) ;
  dsg.addGraph(n, model.getGraph() ) ;
  return this;
}

  @Override
  public QueryIterator exec(Binding binding, PropFuncArg argSubject,
      Node predicate, PropFuncArg argObject, ExecutionContext execCxt) {

    argSubject = Substitute.substitute(argSubject, binding);
    argObject = Substitute.substitute(argObject, binding);
    
    if(!argObject.getArg().isVariable()) {
      throw new ExprEvalException("Right hand side of tosh:targetContains must be a variable");
    }
    
    Node targetNode = argSubject.getArgList().get(0);
    Node shapesGraphNode = argSubject.getArgList().get(1);
    
    Model currentModel = ModelFactory.createModelForGraph(execCxt.getActiveGraph());
    Dataset dataset = new DatasetWithDifferentDefaultModel(currentModel, DatasetImpl.wrap(execCxt.getDataset()));

    Model model = dataset.getNamedModel(shapesGraphNode.getURI());
    Resource target = (Resource) model.asRDFNode(targetNode);

    Set<Node> focusNodes = new HashSet<Node>();
    SHACLUtil.addNodesInTarget(target, dataset, focusNodes);
    return new QueryIterExtendByVar(binding, (Var) argObject.getArg(), focusNodes.iterator(), execCxt);
  }
}

/**
 * Specifies a Dataset that shall be used for query execution.
 * Returns a new DatasetImpl by default but may be overloaded in subclasses.
 * For example, TopBraid delegates this to the currently open Graphs.
 * @param defaultModel  the default Model of the Dataset
 * @return the Dataset
 */
public Dataset getDataset(Model defaultModel) {
  if(defaultModel != null) {
    return new DatasetImpl(defaultModel);
  }
  else {
    return new DatasetImpl(JenaUtil.createMemoryModel());
  }
}

@Override
public void begin(ReadWrite mode) {
  checkTransactional();
  transactional.begin(mode);
}

  @Override
  public QueryIterator exec(Binding binding, PropFuncArg argSubject,
      Node predicate, PropFuncArg argObject, ExecutionContext execCxt) {

    argSubject = Substitute.substitute(argSubject, binding);
    argObject = Substitute.substitute(argObject, binding);
    
    if(!argObject.getArg().isVariable()) {
      throw new ExprEvalException("Right hand side of tosh:targetContains must be a variable");
    }
    
    Node targetNode = argSubject.getArgList().get(0);
    Node shapesGraphNode = argSubject.getArgList().get(1);
    
    Model currentModel = ModelFactory.createModelForGraph(execCxt.getActiveGraph());
    Dataset dataset = new DatasetWithDifferentDefaultModel(currentModel, DatasetImpl.wrap(execCxt.getDataset()));

    Model model = dataset.getNamedModel(shapesGraphNode.getURI());
    Resource target = (Resource) model.asRDFNode(targetNode);

    Set<Node> focusNodes = new HashSet<Node>();
    SHACLUtil.addNodesInTarget(target, dataset, focusNodes);
    return new QueryIterExtendByVar(binding, (Var) argObject.getArg(), focusNodes.iterator(), execCxt);
  }
}