Class Connections

java.lang.Object
org.eclipse.rdf4j.repository.util.Connections

public class Connections extends Object
Convenience functions for use with RepositoryConnections.
Author:
Jeen Broekstra
  • Constructor Details

    • Connections

      public Connections()
  • Method Details

    • consumeRDFCollection

      public static void consumeRDFCollection(RepositoryConnection conn, Resource head, Consumer<Statement> collectionConsumer, Resource... contexts) throws RepositoryException
      Retrieve all Statements that together form the RDF Collection starting with the supplied start resource and send them to the supplied Consumer.
      Parameters:
      conn - the RepositoryConnection to use for statement retrieval.
      head - the start resource of the RDF Collection. May not be null.
      collectionConsumer - a Consumer function to which all retrieved statements will be reported. May not be null.
      contexts - the context(s) from which to read the RDF Collection. This argument is an optional vararg and can be left out.
      Throws:
      RepositoryException - if an error occurred while reading the collection statements, for example if a cycle is detected in the RDF collection, or some other anomaly which makes it non-wellformed.
      See Also:
    • getRDFCollection

      public static <C extends Collection<Statement>> C getRDFCollection(RepositoryConnection conn, Resource head, C statementCollection, Resource... contexts) throws RepositoryException
      Retrieve all Statements that together form the RDF Collection starting with the supplied starting resource.
      Parameters:
      conn - the RepositoryConnection to use for statement retrieval.
      head - the start resource of the RDF Collection. May not be null.
      statementCollection - a Collection of Statements (for example, a Model) to which all retrieved statements will be reported. May not be null.
      contexts - the context(s) from which to read the RDF Collection. This argument is an optional vararg and can be left out.
      Returns:
      the input statement collection, with the statements forming the retrieved RDF Collection added.
      Throws:
      RepositoryException - if an error occurred while reading the collection statements, for example if a cycle is detected in the RDF collection, or some other anomaly which makes it non-wellformed.
      See Also:
    • getStatement

      public static Optional<Statement> getStatement(RepositoryConnection conn, Resource subject, IRI predicate, Value object, Resource... contexts) throws RepositoryException
      Retrieve a single Statement matching with the supplied subject, predicate, object and context(s) from the given RepositoryConnection. If more than one Statement matches, any one Statement is selected and returned.
      Parameters:
      conn - the RepositoryConnection from which to retrieve the statement.
      subject - the subject to which the statement should match. May be null.
      predicate - the predicate to which the statement should match. May be null.
      object - the object to which the statement should match. May be null .
      contexts - the context(s) from which to read the Statement. This argument is an optional vararg and can be left out.
      Returns:
      an Optional of Statement. If no matching Statement was found, Optional.empty() is returned.
      Throws:
      RepositoryException