package org.apache.commons.rdf;

/**
 * An <a href= "http://www.w3.org/TR/rdf11-concepts/#dfn-rdf-triple" >RDF-1.1
 * Triple</a>, as defined by <a href= "http://www.w3.org/TR/rdf11-concepts/"
 * >RDF-1.1 Concepts and Abstract Syntax</a>, a W3C Recommendation published on
 * 25 February 2014.<br>
 *
 * @see <a href= "http://www.w3.org/TR/rdf11-concepts/#dfn-rdf-triple" >RDF-1.1
 * Triple</a>
 */
public interface Triple {

    /**
     * The subject of this triple, which may be either a {@link BlankNode} or an
     * {@link IRI}, which are represented in Commons RDF by the interface
     * {@link BlankNodeOrIRI}.
     *
     * @return The subject {@link BlankNodeOrIRI} of this triple.
     * @see <a href="http://www.w3.org/TR/rdf11-concepts/#dfn-subject">RDF-1.1
     * Triple subject</a>
     */
    BlankNodeOrIRI getSubject();

    /**
     * The predicate {@link IRI} of this triple.
     *
     * @return The predicate {@link IRI} of this triple.
     * @see <a href="http://www.w3.org/TR/rdf11-concepts/#dfn-predicate">RDF-1.1
     * Triple predicate</a>
     */
    IRI getPredicate();

    /**
     * The object of this triple, which may be either a {@link BlankNode}, an
     * {@link IRI}, or a {@link Literal}, which are represented in Commons RDF
     * by the interface {@link RDFTerm}.
     *
     * @return The object {@link RDFTerm} of this triple.
     * @see <a href="http://www.w3.org/TR/rdf11-concepts/#dfn-object">RDF-1.1
     * Triple object</a>
     */
    RDFTerm getObject();

}