/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.apache.jena.ontapi.model;

import org.apache.jena.graph.Graph;
import org.apache.jena.graph.Triple;
import org.apache.jena.ontapi.OntJenaException;
import org.apache.jena.ontapi.common.OntPersonality;
import org.apache.jena.ontapi.utils.Graphs;
import org.apache.jena.rdf.model.InfModel;
import org.apache.jena.rdf.model.Literal;
import org.apache.jena.rdf.model.Model;
import org.apache.jena.rdf.model.Property;
import org.apache.jena.rdf.model.RDFList;
import org.apache.jena.rdf.model.RDFNode;
import org.apache.jena.rdf.model.Resource;
import org.apache.jena.rdf.model.Statement;
import org.apache.jena.vocabulary.OWL2;
import org.apache.jena.vocabulary.RDF;
import org.apache.jena.vocabulary.RDFS;
import org.apache.jena.vocabulary.XSD;

import java.util.Collection;
import java.util.Objects;
import java.util.Optional;
import java.util.stream.Stream;

/**
 * An enhanced view of a {@link Model Jena Model} about which is known
 * to contain <b>OWL</b> or <b>RDFS</b> ontology data.
 * The view supports OWL2 DL specification,
 * and is an analogue of {@link org.apache.jena.ontology.OntModel Apache Jena OntModel},
 * which only covers the OWL1 syntax.
 * <p>
 * In addition to the standard {@link Resource Jena Resource}s and {@link Statement Jena Statement}s
 * this model provides access to different ontological components in the form of {@link OntObject Object}s
 * and {@link OntStatement Ontology Statement}s that support OWL Annotations.
 * Some of the {@link OntObject}s can be constructed using another kind of resource -
 * {@link OntList}, which is an extended analogue of the standard {@link RDFList Jena RDFList}.
 * <p>
 * The model also has a component-level support of Semantic Web Rule Language (SWRL).
 * <p>
 * In additional to native Jena {@link org.apache.jena.util.iterator.ExtendedIterator Extended Iterator}s,
 * this model also provides access to RDF in the form of {@link Stream}s, that obey the same rules:
 * both {@code Stream} and {@code ExtendedIterator} must be closed explicitly
 * if they are no longer needed but not yet exhausted, see {@link org.apache.jena.util.iterator.ClosableIterator}.
 * <p>
 * Impl note: this model does not support {@link org.apache.jena.ontology.Profile Jena Profile}s mechanism,
 * and model configuration is delegated directly to the extended {@link OntPersonality Personality}.
 * <p>
 * The interface does not extend {@link InfModel},
 * but the inference model can be accessed via {@link OntModel#asInferenceModel()}.
 * If implementation does not provide inference support, the method will throw an exception.
 *
 * @see org.apache.jena.ontology.OntModel
 * @see <a href="https://www.w3.org/TR/owl2-mapping-to-rdf">OWL2 RDF mapping</a>
 * @see <a href="https://www.w3.org/TR/owl2-quick-reference/">A Quick Guide</a>
 * @see <a href="https://www.w3.org/TR/owl2-syntax/">OWL 2 Web Ontology Language Structural Specification and Functional-Style Syntax (Second Edition)</a>
 * @see <a href="https://www.w3.org/Submission/SWRL/">SWRL: A Semantic Web Rule Language Combining OWL and RuleML</a>
 */
public interface OntModel extends Model,
        MutableModel<OntModel>, PrefixedModel<OntModel>, IOModel<OntModel>,
        CreateClasses, CreateRanges, CreateDisjoint, CreateSWRL {

    /**
     * Returns the base {@code Graph},
     * i.e., the primary ontological {@code Graph} that does not contain any subgraph hierarchy.
     * Only the base graph can be edited from this interface view.
     * To get the whole union graph use the method {@link #getGraph()}.
     *
     * @return {@link Graph}
     * @see #getGraph()
     */
    Graph getBaseGraph();

    /**
     * Finds an Ontology ID object.
     * <p>
     * Since OWL2 graph requires only one {@code @uri rdf:type owl:Ontology} triple,
     * the method returns {@code Optional#empty} in other cases.
     * No changes in the {@code Graph} is made.
     * The method works only with the {@link #getBaseGraph() base graph}.
     *
     * @return an {@code Optional} that contains the {@link OntID}
     * @see #setID(String)
     * @see Graphs#ontologyNode
     */
    Optional<OntID> id();

    /**
     * Creates a new {@code @uri rdf:type owl:Ontology} statement for the specified {@code uri}
     * and wraps it as Ontology ID Resource.
     * Removes all extra ontology objects if they are present and moves their content to the new one,
     * to have a single Ontology header as it is required by OWL2 specification.
     *
     * @param uri String, can be {@code null} to make this ontology to be anonymous
     * @return the new {@link OntID} instance
     * @throws OntJenaException if ontology can't be added (e.g. due to collision with imports)
     * @see #getID()
     */
    OntID setID(String uri);

    /**
     * Adds a sub-model both to the {@code owl:import} section and to the graph hierarchy.
     *
     * @param m {@link OntModel ont jena model} to add, not {@code null}
     * @return this model to allow cascading calls
     * @throws OntJenaException if specified, ontology is anonymous
     *                          or already present in the imports (both as graph and in owl-declaration)
     * @see OntID#addImport(String)
     */
    OntModel addImport(OntModel m) throws OntJenaException;

    /**
     * Removes a sub-model from {@code owl:import} and from the graph hierarchy.
     * Does nothing if the specified model does not belong to this ontology.
     * Matching is performed by graph, not uri (see {@link #hasImport(OntModel)} description).
     *
     * @param m {@link OntModel ont jena model} to remove, not {@code null}
     * @return <b>this</b> model to allow cascading calls
     * @see OntID#removeImport(String)
     * @see #hasImport(OntModel)
     */
    OntModel removeImport(OntModel m);

    /**
     * Removes the import (both {@code owl:import} declaration and the corresponding graph)
     * by the given uri if it is found.
     *
     * @param uri String, an iri of ontology to find, not {@code null}
     * @return <b>this</b> model to allow cascading calls
     * @see OntID#getImportsIRI()
     * @see #hasImport(String)
     */
    OntModel removeImport(String uri);

    /**
     * Lists all sub-models
     * that belong to the top-level hierarchy and have {@code owl:import} reference inside the base graph.
     * Caution: since recursive hierarchies are not prohibited,
     * the rectilinear usage of this method may cause a StackOverflow Error.
     *
     * @return {@code Stream} of {@link OntModel}s
     * @see OntID#imports()
     */
    Stream<OntModel> imports();

    /**
     * Answers {@code true} if the given model is present in the {@link OWL2#imports owl:imports} of this model.
     * This means that at the top-level of the import hierarchy there is a base graph of the given {@code other} model.
     * Please note: the model may contain the same uri as that of the specified model, but a different (base) graph,
     * i.e. if the method {@link #hasImport(String)} returns {@code true},
     * it does not mean this method also returns {@code true}.
     *
     * @param other {@link OntModel} to test, not {@code null}
     * @return {@code true} if the model is in imports
     */
    boolean hasImport(OntModel other);

    /**
     * Answers {@code true} if the model has a graph with the given uri both in {@code owl:imports} and graph-hierarchy.
     *
     * @param uri String, not {@code null}
     * @return boolean
     * @see OntID#getImportsIRI()
     */
    boolean hasImport(String uri);

    /**
     * Lists all ont-objects of the specified type.
     * Note: this method may return non-distinct results, it is implementation dependent.
     *
     * @param type {@link Class} the concrete type of {@link OntObject}, not {@code null}
     * @param <O>  any ont-object subtype
     * @return {@code Stream} of {@link OntObject}s of the type {@code O}
     * @see #ontEntities()
     */
    <O extends OntObject> Stream<O> ontObjects(Class<? extends O> type);

    /**
     * Lists all entities declared in the model.
     * Built-ins are not included.
     * The retrieved entities can belong to the underlying graphs also.
     * Note: this method returns non-distinct stream.
     * The duplicate elements (by {@code equals} and {@code hasCode}, not by real class-type)
     * means that there is so-called punning.
     *
     * @return {@code Stream} of {@link OntEntity}
     * @see #ontObjects(Class)
     * @see #ontEntities(Class)
     */
    Stream<OntEntity> ontEntities();

    /**
     * Lists all class-asserted individuals.
     * <p>
     * A class assertion axiom is a statement {@code a rdf:type C},
     * where {@code a} is a retrieving individual (named or anonymous) and {@code C} is any class expression.
     * Notice, that the method {@link OntModel#ontObjects(Class)}
     * called with the parameter {@code OntIndividual.class}
     * (i.e. {@code model.ontObject(OntIndividual.class)}) must return all individuals from a model,
     * even those which have no explicit declarations (e.g. any part of {@code owl:sameAs} is an individual),
     * while this method returns only class-asserted individuals.
     * Also notice: the method {@link #namedIndividuals()} must return only explicitly declared named individuals,
     * while this method does not require the declaration {@link OWL2#NamedIndividual owl:NamedIndividual}
     * to be present for an individual: according to the specification, it is optional; for more details see
     * <a href="https://www.w3.org/TR/owl2-syntax/#Typing_Constraints_of_OWL_2_DL">5.8.1 Typing Constraints of OWL 2 DL</a>.
     * Also note: in case of valid distinct {@link #getGraph() RDF graph}
     * the returned {@code Stream} is also distinct,
     * which means an individual that has more than one class assertions, must appear in the stream only once.
     *
     * @return {@code Stream} of {@link OntIndividual}s
     * @see OntModel#namedIndividuals()
     */
    Stream<OntIndividual> individuals();

    /**
     * Returns an ont-entity for the specified type and uri.
     * This method can also be used to wrap builtin entities, which, in fact, do not belong to the RDF graph,
     * but can be considered as belonged to the OWL model.
     * An IRI for such a built-in entity must be in
     * the {@link OntPersonality.Builtins Builtins Vocabulary},
     * otherwise the method returns {@code null}.
     *
     * @param type {@link Class}, the type of {@link OntEntity}, not {@code null}.
     * @param uri String, not {@code null}.
     * @param <E>  type of ont-entity
     * @return {@link OntEntity} or {@code null}
     * @see #fetchOntEntity(Class, String)
     */
    @SuppressWarnings("javadoc")
    <E extends OntEntity> E getOntEntity(Class<E> type, String uri);

    /**
     * Lists all ont-statements.
     *
     * @return {@code Stream} of {@link OntStatement}
     * @see Model#listStatements()
     */
    Stream<OntStatement> statements();

    /**
     * Lists all statements for the specified subject, predicate and object (SPO).
     *
     * @param s {@link Resource}, the subject
     * @param p {@link Property}, the predicate
     * @param o {@link RDFNode}, the object
     * @return {@code Stream} of {@link OntStatement}
     * @see Model#listStatements(Resource, Property, RDFNode)
     */
    Stream<OntStatement> statements(Resource s, Property p, RDFNode o);

    /**
     * Lists all statements from the {@link OntModel#getBaseGraph() base graph}
     * for the specified subject, predicate and object.
     * Effectively equivalent to the {@code model.statements(s, p, o).filter(OntStatement::isLocal)} expression.
     *
     * @param s {@link Resource}, the subject
     * @param p {@link Property}, the predicate
     * @param o {@link RDFNode}, the object
     * @return {@code Stream} of {@link OntStatement}
     * @see OntModel#statements(Resource, Property, RDFNode)
     * @see OntStatement#isLocal()
     */
    Stream<OntStatement> localStatements(Resource s, Property p, RDFNode o);

    /**
     * Answers an {@link OntStatement Ontology Statement} in this model who's SPO is that of the {@code triple}.
     *
     * @param triple {@link Triple}, not {@code null}
     * @return {@link OntStatement}
     */
    @Override
    OntStatement asStatement(Triple triple);

    /**
     * Removes the given {@link OntObject Ontology Object} from the graph-model
     * including its {@link OntObject#content() content} and annotations.
     * This operation does not guarantee the removal of all references to objects:
     * it takes into account only statements where the given object in a subject position.
     * For example, in case of deleting an OWL class
     * that is on the right side in a statement with the predicate {@code rdfs:subClassOf},
     * that statement remains unchanged in the graph, but becomes meaningless:
     * its right side will no longer be a class, but just uri.
     * But if a class is on the left side of the statement with the {@code rdfs:subClassOf} predicate,
     * that statement is being removed from the graph along with its annotations,
     * because it belongs to the class content.
     *
     * @param obj {@link OntObject}
     * @return <b>this</b> model
     * @see OntObject#content()
     */
    OntModel removeOntObject(OntObject obj);

    /**
     * Removes the statement from the graph-model including its annotations with sub-annotations hierarchy.
     *
     * @param statement {@link OntStatement}
     * @return <b>this</b> model
     * @see #remove(Statement)
     */
    OntModel removeOntStatement(OntStatement statement);

    /**
     * Creates an owl-entity by the {@code type} and {@code iri}.
     *
     * @param type {@link Class}, the type of {@link OntEntity}, not {@code null}
     * @param iri  String, not {@code null}
     * @param <E>  type of ont-entity
     * @return {@link OntEntity}
     * @throws OntJenaException.Creation in case something is wrong
     *                                   (e.g. configuration does not support creation of the specified type)
     * @see #getOntEntity(Class, String)
     */
    <E extends OntEntity> E createOntEntity(Class<E> type, String iri);

    /**
     * Creates a facet restriction by the given type and literal value.
     * Each call to this method creates a fresh b-node within the graph.
     *
     * @param type    {@link Class}, the type of {@link OntFacetRestriction}, not {@code null}
     * @param literal {@link Literal}, not {@code null}
     * @param <F>     type of ont-facet-restriction
     * @return {@link OntFacetRestriction}
     * @see OntDataRange.Restriction
     * @see OntModel#createDataRestriction(OntDataRange.Named, Collection)
     */
    <F extends OntFacetRestriction> F createFacetRestriction(Class<F> type, Literal literal);

    /**
     * Returns the {@link Model standard jena model} that corresponds to the {@link #getBaseGraph() base graph}.
     * Note: there is the {@link org.apache.jena.enhanced.BuiltinPersonalities#model Jena Builtin Personality}
     * within the returned model.
     *
     * @return {@link Model}
     * @see #getBaseGraph()
     */
    Model getBaseModel();

    /*
     * ================
     * Default methods:
     * ================
     */

    /**
     * Returns a view of this model that supports inference, if possible.
     *
     * @return {@link InfModel}, not {@code null}
     * @throws OntJenaException.Unsupported if implementation does not support inference,
     *                                      or there is no reasoner attached to the model
     */
    default InfModel asInferenceModel() {
        throw new OntJenaException.Unsupported("Inference is not supported");
    }

    /**
     * Gets the Ontology ID object.
     * <p>
     * Since OWL2 graph can only contain the one {@code @uri rdf:type owl:Ontology} triple inside,
     * this method creates such a statement if it absent;
     * in case there are more than one {@code Resource} with the type equaled to {@link OWL2#Ontology owl:Ontology},
     * it chooses the most bulky one (i.e. those that contains the largest number of associated statements)
     * and all the others leave intact.
     *
     * @return {@link OntID} an existing or fresh {@link Resource},
     * that is subject in the {@code _:x rdf:type owl:Ontology} statement
     */
    default OntID getID() {
        return id().orElseGet(() -> setID(null));
    }

    /**
     * Creates named class (owl-entity)
     *
     * @param uri IRI of class
     * @return named class
     */
    default OntClass.Named createOntClass(String uri) {
        return createOntEntity(OntClass.Named.class, Objects.requireNonNull(uri));
    }

    /**
     * Creates named datatype (owl-entity), only for OWL2
     *
     * @param uri IRI of datarange
     * @return named datarange
     */
    default OntDataRange.Named createDatatype(String uri) {
        return createOntEntity(OntDataRange.Named.class, Objects.requireNonNull(uri));
    }

    /**
     * Creates named individual (owl-entity), only for OWL2 if {@code owl:NamedIndividual} is enabled.
     *
     * @param uri IRI of individual
     * @return named individual
     */
    default OntIndividual.Named createIndividual(String uri) {
        return createOntEntity(OntIndividual.Named.class, Objects.requireNonNull(uri));
    }

    /**
     * Creates named {@code rdf:Property}.
     *
     * @param uri {@code <uri> a rdf:Property}
     * @return {@link OntProperty}
     */
    default OntProperty createRDFProperty(String uri) {
        return createResource(Objects.requireNonNull(uri)).addProperty(RDF.type, RDF.Property).as(OntProperty.class);
    }

    /**
     * Creates annotation property (owl-entity).
     * @param uri IRI of annotation property
     * @return annotation property
     */
    default OntAnnotationProperty createAnnotationProperty(String uri) {
        return createOntEntity(OntAnnotationProperty.class, Objects.requireNonNull(uri));
    }

    /**
     * Creates datatype property (owl-entity).
     * @param uri IRI of datatype property
     * @return datatype property
     */
    default OntDataProperty createDataProperty(String uri) {
        return createOntEntity(OntDataProperty.class, Objects.requireNonNull(uri));
    }

    /**
     * Creates named object property (owl-entity).
     * @param uri IRI of object property
     * @return named object property
     */
    default OntObjectProperty.Named createObjectProperty(String uri) {
        return createOntEntity(OntObjectProperty.Named.class, Objects.requireNonNull(uri));
    }

    /**
     * Creates individual (named or anonymous) of the specified type.
     *
     * @param uri  String, or {@code null} for anonymous individual
     * @param type {@link OntClass}
     * @return {@link OntIndividual}
     */
    default OntIndividual createIndividual(String uri, OntClass type) {
        OntIndividual res;
        if (uri == null) {
            res = createResource().addProperty(RDF.type, type).as(OntIndividual.class);
        } else {
            res = createIndividual(uri).attachClass(type);
        }
        return res;
    }

    default OntClass.Named getOntClass(String uri) {
        return getOntEntity(OntClass.Named.class, uri);
    }

    default OntDataRange.Named getDatatype(String uri) {
        return getOntEntity(OntDataRange.Named.class, uri);
    }

    default OntIndividual.Named getIndividual(String uri) {
        return getOntEntity(OntIndividual.Named.class, uri);
    }

    default OntAnnotationProperty getAnnotationProperty(String uri) {
        return getOntEntity(OntAnnotationProperty.class, uri);
    }

    default OntDataProperty getDataProperty(String uri) {
        return getOntEntity(OntDataProperty.class, uri);
    }

    default OntObjectProperty.Named getObjectProperty(String uri) {
        return getOntEntity(OntObjectProperty.Named.class, uri);
    }

    default OntClass.Named getOntClass(Resource uri) {
        return getOntClass(uri.getURI());
    }

    default OntDataRange.Named getDatatype(Resource uri) {
        return getDatatype(uri.getURI());
    }

    default OntIndividual.Named getIndividual(Resource uri) {
        return getIndividual(Objects.requireNonNull(uri.getURI()));
    }

    default OntAnnotationProperty getAnnotationProperty(Resource uri) {
        return getAnnotationProperty(uri.getURI());
    }

    default OntDataProperty getDataProperty(Resource uri) {
        return getDataProperty(uri.getURI());
    }

    default OntObjectProperty.Named getObjectProperty(Resource uri) {
        return getObjectProperty(uri.getURI());
    }

    default Stream<OntStatement> localStatements() {
        return localStatements(null, null, null);
    }

    default <E extends OntEntity> Stream<E> ontEntities(Class<E> type) {
        return ontObjects(type);
    }

    /**
     * Retrieves a {@link OntDataRange.Named datatype} from the given literal.
     *
     * @param literal {@link Literal}, not {@code null}
     * @return {@link OntDataRange.Named}
     */
    default OntDataRange.Named getDatatype(Literal literal) {
        String uri = literal.getDatatypeURI();
        if (uri != null) {
            return getDatatype(uri);
        }
        String lang = literal.getLanguage();
        if (lang != null && !lang.isEmpty()) {
            return getDatatype(RDF.langString);
        }
        return getDatatype(XSD.xstring);
    }

    /**
     * Returns an entity of the given type and with the specified URI, creating it if needed.
     *
     * @param type a class-type of entity
     * @param uri  String uri, not {@code null}
     * @param <E>  any subtype of {@link OntEntity}
     * @return {@code E}
     */
    default <E extends OntEntity> E fetchOntEntity(Class<E> type, String uri) {
        E res = getOntEntity(type, uri);
        return res == null ? createOntEntity(type, uri) : res;
    }

    /**
     * Lists all named class expressions (OWL classes).
     *
     * @return {@code Stream} of {@link OntClass.Named Ontology Class}es
     */
    default Stream<OntClass.Named> classes() {
        return ontEntities(OntClass.Named.class);
    }

    /**
     * Answers a {@code Stream} over the classes in this ontology model
     * that represent the uppermost nodes of the class hierarchy.
     * Built-ins are not included.
     *
     * @return a {@code Stream} of the root {@link OntClass classes} in the local class hierarchy
     */
    default Stream<OntClass> hierarchyRoots() {
        return ontObjects(OntClass.class)
                .filter(c -> !c.isURIResource() || !c.asNamed().isBuiltIn())
                .filter(OntClass::isHierarchyRoot);
    }

    /**
     * Lists all OntProperties.
     * The result includes not only OWL properties
     * (Named and Inverse ObjectProperties, DatatypeProperties, AnnotationProperties),
     * but also RDF-properties ({@code <uri> rdf:type rdf:Property}).
     * <p>
     * For getting only OWL Properties, use
     * {@code
     * Stream.of(m.objectProperties(), m.dataProperties(), m.annotationProperties()).flatMap(it -> it)
     * }.
     * If you need all named properties, use {@code this.ontEntities(OntNamedProperty.class)}
     * <p>
     * This is analogous of {@link org.apache.jena.ontology.OntModel#listAllOntProperties()}.
     * Note that this method does not care about punnings: it will return property
     * even if it has both {@code owl:ObjectProperty} and {@code owl:DatatypeProperty} declarations
     * and such punning is prohibited in the model settings.
     *
     * @return <b>distinct</b> {@code Stream} of {@link OntProperty OntProperty}s
     */
    default Stream<OntProperty> properties() {
        return ontObjects(OntProperty.class);
    }

    /**
     * Lists all annotation properties.
     *
     * @return {@code Stream} of {@link OntAnnotationProperty Annotation Property}s
     */
    default Stream<OntAnnotationProperty> annotationProperties() {
        return ontEntities(OntAnnotationProperty.class);
    }

    /**
     * Lists all data properties.
     *
     * @return {@code Stream} of {@link OntDataProperty Data Property}s
     */
    default Stream<OntDataProperty> dataProperties() {
        return ontEntities(OntDataProperty.class);
    }

    /**
     * Lists all named object property expressions (object properties in short).
     *
     * @return {@code Stream} of {@link OntObjectProperty.Named Named Object Property}s
     */
    default Stream<OntObjectProperty.Named> objectProperties() {
        return ontEntities(OntObjectProperty.Named.class);
    }

    /**
     * Lists all datatypes (named data range expressions).
     *
     * @return {@code Stream} of {@link OntDataRange.Named Ontology Datatype}s
     */
    default Stream<OntDataRange.Named> datatypes() {
        return ontEntities(OntDataRange.Named.class);
    }

    /**
     * Lists all named individuals,
     * i.e. all those individuals which have explicitly {@link OWL2#NamedIndividual owl:NamedIndividual} declaration.
     *
     * @return {@code Stream} of {@link OntIndividual.Named Named Individual}s
     * @see #individuals()
     * @see OntClass#individuals()
     */
    default Stream<OntIndividual.Named> namedIndividuals() {
        return ontEntities(OntIndividual.Named.class);
    }

    /**
     * Returns {@link OntEntity OWL Entity} with the specified class-type and {@code uri}.
     *
     * @param type {@code Class}, not {@code null}
     * @param uri  {@link Resource}, must be URI, not {@code null}
     * @param <E>  any {@link OntEntity} subtype, not {@code null}
     * @return a {@code E} instance
     */
    default <E extends OntEntity> E getOntEntity(Class<E> type, Resource uri) {
        return getOntEntity(type, uri.getURI());
    }

    /*
     * ===================================
     * Some common built-in OWL2 entities:
     * ===================================
     */

    default OntAnnotationProperty getRDFSComment() {
        return getAnnotationProperty(RDFS.comment);
    }

    default OntAnnotationProperty getRDFSLabel() {
        return getAnnotationProperty(RDFS.label);
    }

    default OntAnnotationProperty getRDFSSeeAlso() {
        return getAnnotationProperty(RDFS.seeAlso);
    }

    default OntAnnotationProperty getRDFSIsDefinedBy() {
        return getAnnotationProperty(RDFS.isDefinedBy);
    }

    default OntAnnotationProperty getOWLDeprecated() {
        return getAnnotationProperty(OWL2.deprecated);
    }

    default OntAnnotationProperty getOWLVersionInfo() {
        return getAnnotationProperty(OWL2.versionInfo);
    }

    default OntAnnotationProperty getOWLPriorVersion() {
        return getAnnotationProperty(OWL2.priorVersion);
    }

    default OntAnnotationProperty getOWLBackwardCompatibleWith() {
        return getAnnotationProperty(OWL2.backwardCompatibleWith);
    }

    default OntAnnotationProperty getOWLIncompatibleWith() {
        return getAnnotationProperty(OWL2.incompatibleWith);
    }

    default OntClass.Named getOWLThing() {
        return getOntClass(OWL2.Thing);
    }

    default OntClass.Named getOWLNothing() {
        return getOntClass(OWL2.Nothing);
    }

    default OntDataRange.Named getRDFSLiteral() {
        return getDatatype(RDFS.Literal);
    }

    default OntObjectProperty.Named getOWLTopObjectProperty() {
        return getObjectProperty(OWL2.topObjectProperty);
    }

    default OntObjectProperty.Named getOWLBottomObjectProperty() {
        return getObjectProperty(OWL2.bottomObjectProperty);
    }

    default OntDataProperty getOWLTopDataProperty() {
        return getDataProperty(OWL2.topDataProperty);
    }

    default OntDataProperty getOWLBottomDataProperty() {
        return getDataProperty(OWL2.bottomDataProperty);
    }
}
