Package org.apache.commons.rdf.api

Interface Triple

All Superinterfaces:

TripleLike

All Known Subinterfaces:

JsonLdTriple, RDF4JTriple

All Known Implementing Classes:

JsonLdTripleImpl, TripleImpl, TripleImpl

public interface Triple
extends TripleLike

An RDF-1.1 Triple, as defined by RDF-1.1 Concepts and Abstract Syntax, a W3C Recommendation published on 25 February 2014.

A Triple object in Commons RDF is considered immutable, that is, over its life time it will have consistent behaviour for its equals(Object), and the RDFTerm instances returned from getSubject(), getPredicate() and getObject() will have consistent RDFTerm.equals(Object) behaviour.

Note that Triple methods are not required to return object identical (==) instances as long as they are equivalent according to RDFTerm.equals(Object). Specialisations of Triple may provide additional methods that are documented to be mutable.

Triple methods are thread-safe, however specialisations may provide additional methods that are documented to not be thread-safe.

Triples can be safely used in hashing collections like HashSet and HashMap.

Any Triple can be used interchangeably across Commons RDF implementations.

See Also:

Quad, RDF.createTriple(BlankNodeOrIRI,IRI,RDFTerm), RDF-1.1 Triple

Method Summary

Modifier and Type	Method	Description
boolean	equals(java.lang.Object other)	Check it this Triple is equal to another Triple.
RDFTerm	getObject()	The object of this triple, which may be either a BlankNode, an IRI, or a Literal, which are represented in Commons RDF by the interface RDFTerm.
IRI	getPredicate()	The predicate IRI of this triple.
BlankNodeOrIRI	getSubject()	The subject of this triple, which may be either a BlankNode or an IRI, which are represented in Commons RDF by the interface BlankNodeOrIRI.
int	hashCode()	Calculate a hash code for this Triple.

Method Detail

getSubject

BlankNodeOrIRI getSubject()

The subject of this triple, which may be either a BlankNode or an IRI, which are represented in Commons RDF by the interface BlankNodeOrIRI.

Specified by:

getSubject in interface TripleLike

Returns:

The subject BlankNodeOrIRI of this triple.

See Also:

RDF-1.1 Triple subject

getPredicate

IRI getPredicate()

The predicate IRI of this triple.

Specified by:

getPredicate in interface TripleLike

Returns:

The predicate IRI of this triple.

See Also:

RDF-1.1 Triple predicate

getObject

RDFTerm getObject()

The object of this triple, which may be either a BlankNode, an IRI, or a Literal, which are represented in Commons RDF by the interface RDFTerm.

Specified by:

getObject in interface TripleLike

Returns:

The object RDFTerm of this triple.

See Also:

RDF-1.1 Triple object

equals

boolean equals(java.lang.Object other)

Check it this Triple is equal to another Triple.

Two Triples are equal if and only if their getSubject(), getPredicate() and getObject() are equal.

Implementations MUST also override hashCode() so that two equal Triples produce the same hash code.

Overrides:

equals in class java.lang.Object

Parameters:

other - Another object

Returns:

true if other is a Triple and is equal to this

See Also:

Object.equals(Object)

hashCode

int hashCode()

Calculate a hash code for this Triple.

The returned hash code MUST be equal to the result of Objects.hash(Object...) with the arguments getSubject(), getPredicate(), getObject().

This method MUST be implemented in conjunction with equals(Object) so that two equal Triples produce the same hash code.

Overrides:

hashCode in class java.lang.Object

Returns:

a hash code value for this Triple.

See Also:

Object.hashCode(), Objects.hash(Object...)