org.jrdf.graph.local
Class GraphImpl

java.lang.Object
  org.jrdf.graph.local.GraphImpl

All Implemented Interfaces:

Graph

public class GraphImpl
extends Object
implements Graph

A memory based RDF Graph.

Version:

$Revision: 1888 $

Author:

Paul Gearon, Andrew Newman

Constructor Summary

GraphImpl(LongIndex[] longIndexes, NodePool newNodePool, ReadWriteGraph newWritableGraph)
Default constructor.

Method Summary

void	add(Iterator<Triple> triples) Adds all the triples contained in an iterator into the graph.
void	add(SubjectNode subject, PredicateNode predicate, ObjectNode object) Adds a triple to the graph.
void	add(Triple... triples) Adds all the triples into the graph.
void	add(Triple triple) Adds a triple to the graph.
void	clear() Removes all statements and resource related to those statements from the graph.
void	close() Closes any resources associated with this graph.
boolean	contains(SubjectNode subject, PredicateNode predicate, ObjectNode object) Test the graph for the occurrence of a statement.
boolean	contains(Triple triple) Test the graph for the occurrence of the triple.
ClosableIterator<Triple>	find(SubjectNode subject, PredicateNode predicate, ObjectNode object) Returns an iterator of Triples to a set of statements that match a given subject, predicate and object.
ClosableIterator<Triple>	find(Triple triple) Returns an iterator of Triples to a set of statements that match a given subject, predicate and object.
ClosableIterator<? extends Node>	findNodes(NodeType type) Returns all unique values of a given type.
ClosableIterator<PredicateNode>	findPredicates(Resource resource) Return predicates that are part of an RDF triple where resource is either a subject or object.
ClosableIterator<? super Resource>	findResources(ValueNodeType type) Returns all unique resources for a given ValueNodeType (BNode or URIReference is currently supported).
GraphElementFactory	getElementFactory() Returns the node factory for the graph, or creates one.
long	getNumberOfTriples() Returns the number of triples in the graph.
TripleFactory	getTripleFactory() Returns the triple factory for the graph, or creates one.
boolean	isEmpty() Returns true if the graph is empty i.e. the number of triples is 0.
void	remove(Iterator<Triple> triples) Removes all the triples contained in an iterator from the graph.
void	remove(SubjectNode subject, PredicateNode predicate, ObjectNode object) Removes a triple from the graph.
void	remove(Triple... triples) Removes all the triples into the graph.
void	remove(Triple triple) Removes a triple from the graph.
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

GraphImpl

public GraphImpl(LongIndex[] longIndexes,
                 NodePool newNodePool,
                 ReadWriteGraph newWritableGraph)

Default constructor.

Method Detail

contains

public boolean contains(Triple triple)
                 throws GraphException

Description copied from interface: Graph

Test the graph for the occurrence of the triple. An AnyNode value for any of the parts of a triple are treated as unconstrained, any values will be returned.

Specified by:

contains in interface Graph

Parameters:

triple - The triple to find.

Returns:

True if the triple is found in the graph, otherwise false.

Throws:

GraphException - If there was an error accessing the graph.

contains

public boolean contains(SubjectNode subject,
                        PredicateNode predicate,
                        ObjectNode object)
                 throws GraphException

Description copied from interface: Graph

Test the graph for the occurrence of a statement. An AnyNode value for any of the parts of a triple are treated as unconstrained, any values will be returned.

Specified by:

contains in interface Graph

Parameters:

subject - The subject to find or AnySubjectNode to indicate any subject.

predicate - The predicate to find or AnyPredicateNode to indicate any predicate.

object - The object to find or AnyObjectNode to indicate any object.

Returns:

True if the statement is found in the model, otherwise false.

Throws:

GraphException - If there was an error accessing the graph.

find

public ClosableIterator<Triple> find(Triple triple)
                              throws GraphException

Description copied from interface: Graph

Returns an iterator of Triples to a set of statements that match a given subject, predicate and object. An AnyNode value for any of the parts of a triple are treated as unconstrained, any values will be returned.

Specified by:

find in interface Graph

Parameters:

triple - The triple to find.

Returns:

an iterator containing the matching statements.

Throws:

GraphException - If there was an error accessing the graph.

find

public ClosableIterator<Triple> find(SubjectNode subject,
                                     PredicateNode predicate,
                                     ObjectNode object)
                              throws GraphException

Description copied from interface: Graph

Returns an iterator of Triples to a set of statements that match a given subject, predicate and object. An AnyNode value for any of the parts of a triple are treated as unconstrained, any values will be returned.

Specified by:

find in interface Graph

Parameters:

subject - The subject to find or AnySubjectNode to indicate any subject.

predicate - The predicate to find or AnyPredicateNode to indicate any predicate.

object - The object to find or AnyObjectNode to indicate any object.

Returns:

an iterator containing the matching statements.

Throws:

GraphException - If there was an error accessing the graph.

findNodes

public ClosableIterator<? extends Node> findNodes(NodeType type)

Description copied from interface: Graph

Returns all unique values of a given type.

Specified by:

findNodes in interface Graph

Parameters:

type - the node type can be positional (SPO) or node type (URIReference, Literal or BNode).

Returns:

all unique values of a given type.

findPredicates

public ClosableIterator<PredicateNode> findPredicates(Resource resource)
                                               throws GraphException

Description copied from interface: Graph

Return predicates that are part of an RDF triple where resource is either a subject or object.

Specified by:

findPredicates in interface Graph

Parameters:

resource - the resource that is either a subject or object in a triple.

Returns:

the unique predicates associated with the resource.

Throws:

GraphException - If there was an error accessing the graph.

findResources

public ClosableIterator<? super Resource> findResources(ValueNodeType type)

Description copied from interface: Graph

Returns all unique resources for a given ValueNodeType (BNode or URIReference is currently supported). Resources are nodes that appear in either the subject or object position.

Specified by:

findResources in interface Graph

Parameters:

type - either BlankNodeType or URIReferenceNodeType.

Returns:

all unique resources.

add

public void add(Iterator<Triple> triples)
         throws GraphException

Description copied from interface: Graph

Adds all the triples contained in an iterator into the graph. The nodes must have already been created using GraphElementFactory.

Specified by:

add in interface Graph

Parameters:

triples - The triple iterator.

Throws:

GraphException - If the statements can't be made.

add

public void add(Triple... triples)
         throws GraphException

Description copied from interface: Graph

Adds all the triples into the graph. The nodes must have already been created using GraphElementFactory.

Specified by:

add in interface Graph

Parameters:

triples - the triples to add.

Throws:

GraphException - If the statements can't be made.

add

public void add(Triple triple)
         throws GraphException

Description copied from interface: Graph

Adds a triple to the graph. The nodes must have already been created using GraphElementFactory.

Specified by:

add in interface Graph

Parameters:

triple - The triple.

Throws:

GraphException - If the statement can't be made.

add

public void add(SubjectNode subject,
                PredicateNode predicate,
                ObjectNode object)
         throws GraphException

Description copied from interface: Graph

Adds a triple to the graph. The nodes must have already been created using GraphElementFactory.

Specified by:

add in interface Graph

Parameters:

subject - The subject.

predicate - The predicate.

object - The object.

Throws:

GraphException - If the statement can't be made.

remove

public void remove(Iterator<Triple> triples)
            throws GraphException

Description copied from interface: Graph

Removes all the triples contained in an iterator from the graph. The nodes must have already been created using GraphElementFactory.

Specified by:

remove in interface Graph

Parameters:

triples - The triple iterator.

Throws:

GraphException - If the statements can't be revoked.

remove

public void remove(Triple... triples)
            throws GraphException

Description copied from interface: Graph

Removes all the triples into the graph. The nodes must have already been created using GraphElementFactory.

Specified by:

remove in interface Graph

Parameters:

triples - the triples to remove.

Throws:

GraphException - If the statements can't be revoked.

remove

public void remove(Triple triple)
            throws GraphException

Description copied from interface: Graph

Removes a triple from the graph. The nodes must have already been created using GraphElementFactory.

Specified by:

remove in interface Graph

Parameters:

triple - The triple.

Throws:

GraphException - If there was an error revoking the statement, For example if it didn't exist.

remove

public void remove(SubjectNode subject,
                   PredicateNode predicate,
                   ObjectNode object)
            throws GraphException

Description copied from interface: Graph

Removes a triple from the graph. The nodes must have already been created using GraphElementFactory.

Specified by:

remove in interface Graph

Parameters:

subject - The subject.

predicate - The predicate.

object - The object.

Throws:

GraphException - If there was an error revoking the statement, For example if it didn't exist.

getElementFactory

public GraphElementFactory getElementFactory()

Description copied from interface: Graph

Returns the node factory for the graph, or creates one.

Specified by:

getElementFactory in interface Graph

Returns:

the node factory for the graph, or creates one.

getTripleFactory

public TripleFactory getTripleFactory()

Description copied from interface: Graph

Returns the triple factory for the graph, or creates one.

Specified by:

getTripleFactory in interface Graph

Returns:

the triple factory for the graph, or creates one.

getNumberOfTriples

public long getNumberOfTriples()
                        throws GraphException

Description copied from interface: Graph

Returns the number of triples in the graph.

Specified by:

getNumberOfTriples in interface Graph

Returns:

the number of triples in the graph.

Throws:

GraphException - If the statements number of statements in the graph fails to be found.

isEmpty

public boolean isEmpty()
                throws GraphException

Description copied from interface: Graph

Returns true if the graph is empty i.e. the number of triples is 0.

Specified by:

isEmpty in interface Graph

Returns:

true if the graph is empty i.e. the number of triples is 0.

Throws:

GraphException - If the statements number of statements in the graph fails to be found.

clear

public void clear()

Description copied from interface: Graph

Removes all statements and resource related to those statements from the graph.

Specified by:

clear in interface Graph

close

public void close()

Description copied from interface: Graph

Closes any resources associated with this graph.

Specified by:

close in interface Graph

toString

public String toString()

Overrides:

toString in class Object