org.jrdf.graph.mem
Class GraphImpl

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

All Implemented Interfaces:

Graph, Serializable

public class GraphImpl

extends Object

implements Graph, Serializable

A memory based RDF Graph.

Version:

$Revision: 1.1 $

Author:

Paul Gearon, Andrew Newman

See Also:

Serialized Form

Constructor Summary

GraphImpl()
Default constructor.

Method Summary

void	add(Iterator triples) Adds an iterator containing triples into the graph.
void	add(SubjectNode subject, PredicateNode predicate, ObjectNode object) Adds a triple to the graph.
void	add(Triple triple) Adds a triple to the graph.
void	close() Closes any underlying resources used by 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	find(SubjectNode subject, PredicateNode predicate, ObjectNode object) Returns an iterator to a set of statements that match a given subject, predicate and object.
ClosableIterator	find(Triple triple) Returns an iterator to a set of statements that match a given subject, predicate and object.
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 triples) Removes an iterator containing triples from the graph.
void	remove(SubjectNode subject, PredicateNode predicate, ObjectNode object) Removes a triple from the graph.
void	remove(Triple triple) Removes a triple from the graph.

Methods inherited from class java.lang.Object

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

Constructor Detail

GraphImpl

public GraphImpl()
          throws GraphException

Default constructor.

Throws:

GraphException - There was an error creating the factory.

Method Detail

contains

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

Test the graph for the occurrence of a statement. A null 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 null to indicate any subject.

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

object - The object to find or null 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.

contains

public boolean contains(Triple triple)
                 throws GraphException

Test the graph for the occurrence of the triple. A null 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.

find

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

Returns an iterator to a set of statements that match a given subject, predicate and object. A null 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 null to indicate any subject.

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

object - ObjectNode The object to find or null to indicate any object.

Returns:

an iterator containing the matching statements.

Throws:

GraphException - If there was an error accessing the graph.

find

public ClosableIterator find(Triple triple)
                      throws GraphException

Returns an iterator to a set of statements that match a given subject, predicate and object. A null 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.

add

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

Adds a triple to the graph.

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.

add

public void add(Triple triple)
         throws GraphException

Adds a triple to the graph.

Specified by:

add in interface Graph

Parameters:

triple - The triple.

Throws:

GraphException - If the statement can't be made.

add

public void add(Iterator triples)
         throws GraphException

Adds an iterator containing triples into the graph.

Specified by:

add in interface Graph

Parameters:

triples - The triple iterator.

Throws:

GraphException - If the statements can't be made.

remove

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

Removes a triple from the graph.

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.

remove

public void remove(Triple triple)
            throws GraphException

Removes a triple from the graph.

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(Iterator triples)
            throws GraphException

Removes an iterator containing triples from the graph.

Specified by:

remove in interface Graph

Parameters:

triples - The triple iterator.

Throws:

GraphException - If the statements can't be revoked.

getElementFactory

public GraphElementFactory getElementFactory()

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()

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

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

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.

close

public void close()

Closes any underlying resources used by this graph.

Specified by:

close in interface Graph