org.eclipse.rdf4j.model.Triple Maven / Gradle / Ivy
/*******************************************************************************
* Copyright (c) 2020 Eclipse RDF4J contributors.
*
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Distribution License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/org/documents/edl-v10.php.
*
* SPDX-License-Identifier: BSD-3-Clause
*******************************************************************************/
package org.eclipse.rdf4j.model;
import org.eclipse.rdf4j.common.annotation.Experimental;
/**
* An RDF-star embedded triple. Embedded triples have a subject, predicate and object. Unlike {@link Statement}, a
* triple never has an associated context.
*
* Additional utility functionality for working with {@code Triple} objects is available in the
* {@link org.eclipse.rdf4j.model.util.Statements} and {@link org.eclipse.rdf4j.model.util.Values} utility classes.
*
* @author Pavel Mihaylov
* @implNote In order to ensure interoperability of concrete classes implementing this interface,
* {@link #equals(Object)} and {@link #hashCode()} methods must be implemented exactly as described in their
* specs.
* @see RDF-star and SPARQL-star Draft Community Group Report
*/
@Experimental
public interface Triple extends Resource {
@Override
default boolean isTriple() {
return true;
}
/**
* Gets the subject of this triple.
*
* @return The triple's subject.
*/
Resource getSubject();
/**
* Gets the predicate of this triple.
*
* @return The triple's predicate.
*/
IRI getPredicate();
/**
* Gets the object of this triple.
*
* @return The triple's object.
*/
Value getObject();
/**
* Compares this triple to another object.
*
* @param other the object to compare this triple to
* @return {@code true} if the {@code other} object is an instance of {@code Triple} and if their
* {@linkplain #getSubject() subjects}, {@linkplain #getPredicate() predicates} and {@linkplain #getObject()
* objects} are equal; {@code false} otherwise
*/
@Override
boolean equals(Object other);
/**
* Computes the hash code of this triple.
*
* @return a hash code for this triple computed as {@link java.util.Objects#hash Objects.hash}(
* {@link #getSubject()}, {@link #getPredicate()}, {@link #getObject()})
*/
@Override
int hashCode();
}