/* This file is part of the OWL API.
 * The contents of this file are subject to the LGPL License, Version 3.0.
 * Copyright 2014, The University of Manchester
 * 
 * This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
 * You should have received a copy of the GNU General Public License along with this program.  If not, see http://www.gnu.org/licenses/.
 *
 * Alternatively, the contents of this file may be used under the terms of the Apache License, Version 2.0 in which case, the provisions of the Apache License Version 2.0 are applicable instead of those above.
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at
 * http://www.apache.org/licenses/LICENSE-2.0
 * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. */
package org.semanticweb.owlapi.model;

import java.util.Collection;

/**
 * Represents an <a href="http://www.w3.org/TR/owl2-syntax/#Inverse_Object_Properties_2" >
 * InverseObjectProperties</a> axiom in the OWL 2 Specification. <br>
 * Represents a statement that two properties are the inverse of each other. This property axiom
 * contains a set of two properties. inverseOf(P, Q) is considered to be equal to inverseOf(Q, P) -
 * i.e. the order in which the properties are specified isn't important.
 *
 * @author Matthew Horridge, The University Of Manchester, Bio-Health Informatics Group
 * @since 2.0.0
 */
public interface OWLInverseObjectPropertiesAxiom
    extends OWLNaryPropertyAxiom<OWLObjectPropertyExpression>, OWLObjectPropertyAxiom {

    @Override
    @SuppressWarnings("unchecked")
    OWLInverseObjectPropertiesAxiom getAxiomWithoutAnnotations();

    @Override
    default OWLObjectType type() {
        return OWLObjectType.INVERSE;
    }

    @Override
    Collection<OWLInverseObjectPropertiesAxiom> asPairwiseAxioms();

    @Override
    Collection<OWLInverseObjectPropertiesAxiom> splitToAnnotatedPairs();

    /**
     * @return the first of the two object properties.
     */
    OWLObjectPropertyExpression getFirstProperty();

    /**
     * @return the second of the two object properties.
     */
    OWLObjectPropertyExpression getSecondProperty();

    /**
     * @return the set of subproperty axioms equivalent
     */
    Collection<OWLSubObjectPropertyOfAxiom> asSubObjectPropertyOfAxioms();

    @Override
    default void accept(OWLObjectVisitor visitor) {
        visitor.visit(this);
    }

    @Override
    default <O> O accept(OWLObjectVisitorEx<O> visitor) {
        return visitor.visit(this);
    }

    @Override
    default AxiomType<?> getAxiomType() {
        return AxiomType.INVERSE_OBJECT_PROPERTIES;
    }
}