Package org.eclipse.rdf4j.sail.memory.model

Class MemValueFactory

java.lang.Object

org.eclipse.rdf4j.model.base.AbstractValueFactory

org.eclipse.rdf4j.sail.memory.model.MemValueFactory

All Implemented Interfaces:

ValueFactory

public class MemValueFactory
extends AbstractValueFactory

A factory for MemValue objects that keeps track of created objects to prevent the creation of duplicate objects, minimizing memory usage as a result.

Author:

Arjohn Kampman, David Huynh

Constructor Summary

Constructors

Constructor	Description
MemValueFactory()	A cache of the most common IRIs to improve lookup performance when users use our vocabularies (eg.

Method Summary

Modifier and Type	Method	Description
void	clear()
BNode	createBNode(String nodeID)	Creates a new blank node with the given node identifier.
IRI	createIRI(String uri)	Creates a new IRI from the supplied string-representation.
IRI	createIRI(String namespace, String localName)	Creates a new IRI from the supplied namespace and local name.
Literal	createLiteral(boolean value)	Creates a new xsd:boolean-typed literal representing the specified value.
Literal	createLiteral(String value)	Creates a new literal with the supplied label.
Literal	createLiteral(String value, String language)	Creates a new literal with the supplied label and language attribute.
Literal	createLiteral(String value, CoreDatatype datatype)	Creates a new literal with the supplied label and datatype.
Literal	createLiteral(String value, IRI datatype)	Creates a new literal with the supplied label and datatype.
Literal	createLiteral(XMLGregorianCalendar calendar)	Creates a new literal representing the specified calendar that is typed using the appropriate XML Schema date/time datatype.
Triple	createTriple(Resource subject, IRI predicate, Value object)	Creates a new RDF-star triple with the supplied subject, predicate and object.
MemBNode	getMemBNode(BNode bnode)	See getMemValue() for description.
WeakObjectRegistry.AutoCloseableIterator<MemBNode>	getMemBNodesIterator()	Gets all bnodes that are managed by this value factory.
WeakObjectRegistry.AutoCloseableIterator<MemIRI>	getMemIRIsIterator()	Gets all URIs that are managed by this value factory.
MemLiteral	getMemLiteral(Literal literal)	See getMemValue() for description.
WeakObjectRegistry.AutoCloseableIterator<MemLiteral>	getMemLiteralsIterator()	Gets all literals that are managed by this value factory.
MemResource	getMemResource(Resource resource)	See getMemValue() for description.
MemIRI	getMemURI(IRI uri)	See getMemValue() for description.
MemValue	getMemValue(Value value)	Returns a previously created MemValue that is equal to the supplied value, or null if the supplied value is a new value or is equal to null.
MemBNode	getOrCreateMemBNode(BNode bnode)	See getOrCreateMemValue(Value) for description.
MemLiteral	getOrCreateMemLiteral(Literal literal)	See getOrCreateMemValue(Value) for description.
MemResource	getOrCreateMemResource(Resource resource)	See getOrCreateMemValue(Value) for description.
MemTriple	getOrCreateMemTriple(Triple triple)	See getOrCreateMemValue(Value) for description.
MemIRI	getOrCreateMemURI(IRI uri)	See getOrCreateMemValue(Value) for description.
MemValue	getOrCreateMemValue(Value value)	Gets or creates a MemValue for the supplied Value.

Methods inherited from class org.eclipse.rdf4j.model.base.AbstractValueFactory

createBNode, createLiteral, createLiteral, createLiteral, createLiteral, createLiteral, createLiteral, createLiteral, createLiteral, createLiteral, createLiteral, createLiteral, createLiteral, createStatement, createStatement

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

MemValueFactory

public MemValueFactory()

A cache of the most common IRIs to improve lookup performance when users use our vocabularies (eg. RDF.TYPE).

Method Details

clear

public void clear()

getMemValue

public MemValue getMemValue(Value value)

Returns a previously created MemValue that is equal to the supplied value, or null if the supplied value is a new value or is equal to null.

Parameters:

value - The MemValue equivalent of the supplied value, or null.

Returns:

A previously created MemValue that is equal to value, or null if no such value exists or if value is equal to null.

getMemResource

public MemResource getMemResource(Resource resource)

See getMemValue() for description.

getMemURI

public MemIRI getMemURI(IRI uri)

See getMemValue() for description.

getMemBNode

public MemBNode getMemBNode(BNode bnode)

See getMemValue() for description.

getMemLiteral

public MemLiteral getMemLiteral(Literal literal)

See getMemValue() for description.

getMemIRIsIterator

public WeakObjectRegistry.AutoCloseableIterator<MemIRI> getMemIRIsIterator()

Gets all URIs that are managed by this value factory.

Returns:

An autocloseable iterator.

getMemBNodesIterator

public WeakObjectRegistry.AutoCloseableIterator<MemBNode> getMemBNodesIterator()

Gets all bnodes that are managed by this value factory.

Returns:

An autocloseable iterator.

getMemLiteralsIterator

public WeakObjectRegistry.AutoCloseableIterator<MemLiteral> getMemLiteralsIterator()

Gets all literals that are managed by this value factory.

Returns:

An autocloseable iterator.

getOrCreateMemValue

public MemValue getOrCreateMemValue(Value value)

Gets or creates a MemValue for the supplied Value. If the factory already contains a MemValue object that is equivalent to the supplied value then this equivalent value will be returned. Otherwise a new MemValue will be created, stored for future calls and then returned.

Parameters:

value - A Resource or Literal.

Returns:

The existing or created MemValue.

getOrCreateMemResource

public MemResource getOrCreateMemResource(Resource resource)

See getOrCreateMemValue(Value) for description.

getOrCreateMemURI

public MemIRI getOrCreateMemURI(IRI uri)

See getOrCreateMemValue(Value) for description.

getOrCreateMemBNode

public MemBNode getOrCreateMemBNode(BNode bnode)

See getOrCreateMemValue(Value) for description.

getOrCreateMemLiteral

public MemLiteral getOrCreateMemLiteral(Literal literal)

See getOrCreateMemValue(Value) for description.

getOrCreateMemTriple

public MemTriple getOrCreateMemTriple(Triple triple)

See getOrCreateMemValue(Value) for description.

createIRI

public IRI createIRI(String uri)

Description copied from interface: ValueFactory

Creates a new IRI from the supplied string-representation.

Specified by:

createIRI in interface ValueFactory

Overrides:

createIRI in class AbstractValueFactory

Parameters:

uri - A string-representation of a IRI.

Returns:

An object representing the IRI.

createIRI

public IRI createIRI(String namespace,
 String localName)

Description copied from interface: ValueFactory

Creates a new IRI from the supplied namespace and local name. Calling this method is funtionally equivalent to calling createIRI(namespace+localName), but allows the ValueFactory to reuse supplied namespace and local name strings whenever possible. Note that the values returned by IRI.getNamespace() and IRI.getLocalName() are not necessarily the same as the values that are supplied to this method.

Specified by:

createIRI in interface ValueFactory

Overrides:

createIRI in class AbstractValueFactory

Parameters:

namespace - The IRI's namespace.

localName - The IRI's local name.

createBNode

public BNode createBNode(String nodeID)

Description copied from interface: ValueFactory

Creates a new blank node with the given node identifier.

Specified by:

createBNode in interface ValueFactory

Overrides:

createBNode in class AbstractValueFactory

Parameters:

nodeID - The blank node identifier.

Returns:

An object representing the blank node.

createLiteral

public Literal createLiteral(String value)

Description copied from interface: ValueFactory

Creates a new literal with the supplied label. The return value of Literal.getDatatype() for the returned object must be xsd:string.

Specified by:

createLiteral in interface ValueFactory

Overrides:

createLiteral in class AbstractValueFactory

Parameters:

value - The literal's label, must not be null.

Returns:

A literal for the specified value.

createLiteral

public Literal createLiteral(String value,
 String language)

Description copied from interface: ValueFactory

Creates a new literal with the supplied label and language attribute. The return value of Literal.getDatatype() for the returned object must be rdf:langString.

Specified by:

createLiteral in interface ValueFactory

Overrides:

createLiteral in class AbstractValueFactory

Parameters:

value - The literal's label, must not be null.

language - The literal's language attribute, must not be null.

Returns:

A literal for the specified value and language attribute.

createLiteral

public Literal createLiteral(String value,
 IRI datatype)

Description copied from interface: ValueFactory

Creates a new literal with the supplied label and datatype.

Specified by:

createLiteral in interface ValueFactory

Overrides:

createLiteral in class AbstractValueFactory

Parameters:

value - The literal's label, must not be null.

datatype - The literal's datatype. If it is null, the datatype xsd:string will be assigned to this literal.

Returns:

A literal for the specified value and type.

createLiteral

public Literal createLiteral(String value,
 CoreDatatype datatype)

Description copied from interface: ValueFactory

Creates a new literal with the supplied label and datatype.

Specified by:

createLiteral in interface ValueFactory

Overrides:

createLiteral in class AbstractValueFactory

Parameters:

value - The literal's label, must not be null.

datatype - The literal's datatype. It may not be null.

createLiteral

public Literal createLiteral(boolean value)

Description copied from interface: ValueFactory

Creates a new xsd:boolean-typed literal representing the specified value.

Specified by:

createLiteral in interface ValueFactory

Overrides:

createLiteral in class AbstractValueFactory

Parameters:

value - The value for the literal.

Returns:

An xsd:boolean-typed literal for the specified value.

createLiteral

public Literal createLiteral(XMLGregorianCalendar calendar)

Description copied from interface: ValueFactory

Creates a new literal representing the specified calendar that is typed using the appropriate XML Schema date/time datatype.

Specified by:

createLiteral in interface ValueFactory

Overrides:

createLiteral in class AbstractValueFactory

Parameters:

calendar - The value for the literal.

Returns:

A typed literal for the specified calendar.

createTriple

public Triple createTriple(Resource subject,
 IRI predicate,
 Value object)

Description copied from interface: ValueFactory

Creates a new RDF-star triple with the supplied subject, predicate and object.

Specified by:

createTriple in interface ValueFactory

Overrides:

createTriple in class AbstractValueFactory

Parameters:

subject - The statement's subject.

predicate - The statement's predicate.

object - The statement's object.

Returns:

The created triple.