org.jrdf.graph
Class AbstractTriple

java.lang.Object
  org.jrdf.graph.AbstractTriple

All Implemented Interfaces:

Serializable, Triple

Direct Known Subclasses:

TripleImpl

public class AbstractTriple
extends Object
implements Triple, Serializable

A base implementation of an RDF Triple.

Version:

$Revision: 2963 $

Author:

Andrew Newman

See Also:

Serialized Form

Field Summary

protected ObjectNode	objectNode The internal representation of the triple - object node.
protected PredicateNode	predicateNode The internal representation of the triple - predicate node.
protected SubjectNode	subjectNode The internal representation of the triple - subject node.

Constructor Summary

AbstractTriple()

Method Summary

boolean	equals(Object obj) Indicates whether some other object is "equal to" this one.
ObjectNode	getObject() Obtains the object of this statement.
PredicateNode	getPredicate() Obtains the predicate of this statement.
SubjectNode	getSubject() Obtains the subject of this statement.
int	hashCode() Returns a hash-code value for this triple.
boolean	isGrounded() Returns true if the subject and object nodes are not blank nodes.
String	toString() Provide a legible representation of a triple.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

subjectNode

protected SubjectNode subjectNode

The internal representation of the triple - subject node.

predicateNode

protected PredicateNode predicateNode

The internal representation of the triple - predicate node.

objectNode

protected ObjectNode objectNode

The internal representation of the triple - object node.

Constructor Detail

AbstractTriple

public AbstractTriple()

Method Detail

getSubject

public SubjectNode getSubject()

Description copied from interface: Triple

Obtains the subject of this statement.

Specified by:

getSubject in interface Triple

Returns:

an SubjectNode which is either a BlankNode or URIReference

getPredicate

public PredicateNode getPredicate()

Description copied from interface: Triple

Obtains the predicate of this statement.

Specified by:

getPredicate in interface Triple

Returns:

a PredicateNode which is a URIReference

getObject

public ObjectNode getObject()

Description copied from interface: Triple

Obtains the object of this statement.

Specified by:

getObject in interface Triple

Returns:

a ObjectNode which is either a BlankNode, URIReference or Literal

isGrounded

public boolean isGrounded()

Description copied from interface: Triple

Returns true if the subject and object nodes are not blank nodes.

Specified by:

isGrounded in interface Triple

Returns:

true if the subject and object nodes are not blank nodes.

equals

public boolean equals(Object obj)

Indicates whether some other object is "equal to" this one.

A triple is equal to another triple if the subject, predicate and object are all equal.

Specified by:

equals in interface Triple

Overrides:

equals in class Object

Parameters:

obj - the reference object with which to compare.

Returns:

true if this object is the same as the obj argument; false otherwise.

hashCode

public int hashCode()

Returns a hash-code value for this triple. The hash code is based upon XORing all of the components of a triple i.e. the subject, predicate and object.

Specified by:

hashCode in interface Triple

Overrides:

hashCode in class Object

Returns:

a hash-code value for this triple.

toString

public String toString()

Provide a legible representation of a triple.

Currently, square brackets with toString values of the parts of the triple.

Overrides:

toString in class Object

Returns:

the string value of the subject, predicate and object in square brackets.