Module org.apache.jena.core
Package org.apache.jena.ontology

Interface OntClass

All Superinterfaces:
FrontsNode, OntResource, RDFNode, Resource
All Known Subinterfaces:
AllValuesFromRestriction, BooleanClassDescription, CardinalityQRestriction, CardinalityRestriction, ComplementClass, EnumeratedClass, HasValueRestriction, IntersectionClass, MaxCardinalityQRestriction, MaxCardinalityRestriction, MinCardinalityQRestriction, MinCardinalityRestriction, QualifiedRestriction, Restriction, SomeValuesFromRestriction, UnionClass
All Known Implementing Classes:
AllValuesFromRestrictionImpl, BooleanClassDescriptionImpl, CardinalityQRestrictionImpl, CardinalityRestrictionImpl, ComplementClassImpl, EnumeratedClassImpl, HasValueRestrictionImpl, IntersectionClassImpl, MaxCardinalityQRestrictionImpl, MaxCardinalityRestrictionImpl, MinCardinalityQRestrictionImpl, MinCardinalityRestrictionImpl, OntClassImpl, QualifiedRestrictionImpl, RestrictionImpl, SomeValuesFromRestrictionImpl, UnionClassImpl
public interface OntClass extends OntResource

Interface that represents an ontology node characterising a class description.

  • Method Details

    • setSuperClass

      void setSuperClass(Resource cls)

      Assert that this class is sub-class of the given class. Any existing statements for subClassOf will be removed.

      Parameters:
      cls - The class that this class is a sub-class of
      Throws:
      ProfileException - If the Profile.SUB_CLASS_OF() property is not supported in the current language profile.

    • addSuperClass

      void addSuperClass(Resource cls)

      Add a super-class of this class.

      Parameters:
      cls - A class that is a super-class of this class.
      Throws:
      ProfileException - If the Profile.SUB_CLASS_OF() property is not supported in the current language profile.

    • getSuperClass

      OntClass getSuperClass()

      Answer a class that is the super-class of this class. If there is more than one such class, an arbitrary selection is made. If there is no such super-class, return null.

      Returns:
      A super-class of this class or null
      Throws:
      ProfileException - If the Profile.SUB_CLASS_OF() property is not supported in the current language profile.

    • listSuperClasses

      ExtendedIterator<OntClass> listSuperClasses()

      Answer an iterator over all of the classes that are super-classes of this class. Each element of the iterator will be an OntClass.

      Returns:
      An iterator over the super-classes of this class.
      Throws:
      ProfileException - If the Profile.SUB_CLASS_OF() property is not supported in the current language profile.

    • listSuperClasses

      ExtendedIterator<OntClass> listSuperClasses(boolean direct)

      Answer an iterator over all of the classes that are super-classes of this class. Each element of the iterator will be an OntClass. See listSubClasses(boolean) for a full explanation of the direct parameter.

      Parameters:
      direct - If true, only answer the directly adjacent classes in the super-class relation: i.e. eliminate any class for which there is a longer route to reach that child under the super-class relation.
      Returns:
      an iterator over the resources representing this class's sub-classes.
      Throws:
      ProfileException - If the Profile.SUB_CLASS_OF() property is not supported in the current language profile.

    • hasSuperClass

      boolean hasSuperClass(Resource cls)

      Answer true if the given class is a super-class of this class.

      Parameters:
      cls - A class to test.
      Returns:
      True if the given class is a super-class of this class.
      Throws:
      ProfileException - If the Profile.SUB_CLASS_OF() property is not supported in the current language profile.

    • hasSuperClass

      boolean hasSuperClass()

      Answer true if this class has any super-class in the model. Note that when using a reasoner, all OWL classes have owl:Thing as a super-class.

      Returns:
      True if this class has any known super-class.
      Throws:
      ProfileException - If the Profile.SUB_CLASS_OF() property is not supported in the current language profile.

    • hasSuperClass

      boolean hasSuperClass(Resource cls, boolean direct)

      Answer true if the given class is a super-class of this class. See listSubClasses(boolean) for a full explanation of the direct parameter.

      Parameters:
      cls - A class to test.
      direct - If true, only search the classes that are directly adjacent to this class in the class hierarchy.
      Returns:
      True if the given class is a super-class of this class.
      Throws:
      ProfileException - If the Profile.SUB_CLASS_OF() property is not supported in the current language profile.

    • removeSuperClass

      void removeSuperClass(Resource cls)

      Remove the given class from the super-classes of this class. If this statement is not true of the current model, nothing happens.

      Parameters:
      cls - A class to be removed from the super-classes of this class
      Throws:
      ProfileException - If the Profile.SUB_CLASS_OF() class is not supported in the current language profile.

    • setSubClass

      void setSubClass(Resource cls)

      Assert that this class is super-class of the given class. Any existing statements for subClassOf on prop will be removed.

      Parameters:
      cls - The class that is a sub-class of this class
      Throws:
      ProfileException - If the Profile.SUB_CLASS_OF() property is not supported in the current language profile.

    • addSubClass

      void addSubClass(Resource cls)

      Add a sub-class of this class.

      Parameters:
      cls - A class that is a sub-class of this class.
      Throws:
      ProfileException - If the Profile.SUB_CLASS_OF() property is not supported in the current language profile.

    • getSubClass

      OntClass getSubClass()

      Answer a class that is the sub-class of this class. If there is more than one such class, an arbitrary selection is made. If there is no such class, return null.

      Returns:
      A sub-class of this class or null
      Throws:
      ProfileException - If the Profile.SUB_CLASS_OF() property is not supported in the current language profile.

    • listSubClasses

      ExtendedIterator<OntClass> listSubClasses()

      Answer an iterator over all of the classes that are declared to be sub-classes of this class. Each element of the iterator will be an OntClass.

      Returns:
      An iterator over the sub-classes of this class.
      Throws:
      ProfileException - If the Profile.SUB_CLASS_OF() property is not supported in the current language profile.

    • listSubClasses

      ExtendedIterator<OntClass> listSubClasses(boolean direct)

      Answer an iterator over the classes that are declared to be sub-classes of this class. Each element of the iterator will be an OntClass. The distinguishing extra parameter for this method is the flag direct that allows some selectivity over the classes that appear in the iterator. Consider the following scenario: 

         :B rdfs:subClassOf :A.
   :C rdfs:subClassOf :A.
   :D rdfs:subClassof :C.
      (so A has two sub-classes, B and C, and C has sub-class D). In a raw model, with no inference support, listing the sub-classes of A will answer B and C. In an inferencing model, rdfs:subClassOf is known to be transitive, so the sub-classes iterator will include D. The direct sub-classes are those members of the closure of the subClassOf relation, restricted to classes that cannot be reached by a longer route, i.e. the ones that are directly adjacent to the given root. Thus, the direct sub-classes of A are B and C only, and not D - even in an inferencing graph. Note that this is not the same as the entailments from the raw graph. Suppose we add to this example: 
         :D rdfs:subClassof :A.
      Now, in the raw graph, A has sub-class C. But the direct sub-classes of A remain B and C, since there is a longer path A-C-D that means that D is not a direct sub-class of A. The assertion in the raw graph that A has sub-class D is essentially redundant, since this can be inferred from the closure of the graph.

      Note: This is a change from the behaviour of Jena 1, which took a parameter closed to compute the closure over transitivity and equivalence of sub-classes. The closure capability in Jena2 is determined by the inference engine that is wrapped with the ontology model. The direct parameter is provided to allow, for example, a level-by-level traversal of the class hierarchy, starting at some given root. Observe that in Jena 1, passing true will tend to increase the number of results returned; in Jena 2 passing true will tend to reduce the number of results.

      Parameters:
      direct - If true, only answer the directly adjacent classes in the sub-class relation: i.e. eliminate any class for which there is a longer route to reach that child under the sub-class relation.
      Returns:
      an iterator over the resources representing this class's sub-classes
      Throws:
      ProfileException - If the Profile.SUB_CLASS_OF() property is not supported in the current language profile.

    • hasSubClass

      boolean hasSubClass(Resource cls)

      Answer true if the given class is a sub-class of this class.

      Parameters:
      cls - A class to test.
      Returns:
      True if the given class is a sub-class of this class.
      Throws:
      ProfileException - If the Profile.SUB_CLASS_OF() property is not supported in the current language profile.

    • hasSubClass

      boolean hasSubClass()

      Answer true if this class has any sub-class in the model. Note that when using a reasoner, all OWL classes have owl:Nothing as a sub-class.

      Returns:
      True if this class has any known sub-class.
      Throws:
      ProfileException - If the Profile.SUB_CLASS_OF() property is not supported in the current language profile.

    • hasSubClass

      boolean hasSubClass(Resource cls, boolean direct)

      Answer true if the given class is a sub-class of this class. See listSubClasses(boolean) for a full explanation of the direct parameter.

      Parameters:
      cls - A class to test.
      direct - If true, only search the classes that are directly adjacent to this class in the class hierarchy.
      Returns:
      True if the given class is a sub-class of this class.
      Throws:
      ProfileException - If the Profile.SUB_CLASS_OF() property is not supported in the current language profile.

    • removeSubClass

      void removeSubClass(Resource cls)

      Remove the given class from the sub-classes of this class. If this statement is not true of the current model, nothing happens.

      Parameters:
      cls - A class to be removed from the sub-classes of this class
      Throws:
      ProfileException - If the Profile.SUB_CLASS_OF() class is not supported in the current language profile.

    • setEquivalentClass

      void setEquivalentClass(Resource cls)

      Assert that the given class is equivalent to this class. Any existing statements for equivalentClass will be removed.

      Parameters:
      cls - The class that this class is a equivalent to.
      Throws:
      ProfileException - If the Profile.EQUIVALENT_CLASS() property is not supported in the current language profile.

    • addEquivalentClass

      void addEquivalentClass(Resource cls)

      Add a class that is equivalent to this class.

      Parameters:
      cls - A class that is equivalent to this class.
      Throws:
      ProfileException - If the Profile.EQUIVALENT_CLASS() property is not supported in the current language profile.

    • getEquivalentClass

      OntClass getEquivalentClass()

      Answer a class that is equivalent to this class. If there is more than one such class, an arbitrary selection is made. See listEquivalentClasses() for a note on equivalent classes when using a reasoner.

      Returns:
      A class equivalent to this class
      Throws:
      ProfileException - If the Profile.EQUIVALENT_CLASS() property is not supported in the current language profile.

    • listEquivalentClasses

      ExtendedIterator<OntClass> listEquivalentClasses()

      Answer an iterator over all of the classes that are known to be equivalent to this class. Equivalence may be asserted in the model (using, for example, owl:equivalentClass, or may be inferred by the reasoner attached to the model. Note that the OWL semantics entails that every class is equivalent to itself, so when using a reasoning model clients should expect that this class will appear as a member of its own equivalent classes.

      Each element of the returned iterator will be an OntClass.

      Returns:
      An iterator over the classes equivalent to this class.
      Throws:
      ProfileException - If the Profile.EQUIVALENT_CLASS() property is not supported in the current language profile.

    • hasEquivalentClass

      boolean hasEquivalentClass(Resource cls)

      Answer true if the given class is equivalent to this class.

      Parameters:
      cls - A class to test for
      Returns:
      True if the given property is equivalent to this class.
      Throws:
      ProfileException - If the Profile.EQUIVALENT_CLASS() property is not supported in the current language profile.

    • removeEquivalentClass

      void removeEquivalentClass(Resource cls)

      Remove the statement that this class and the given class are equivalent. If this statement is not true of the current model, nothing happens.

      Parameters:
      cls - A class that may be declared to be equivalent to this class, and which is no longer equivalent
      Throws:
      ProfileException - If the Profile.EQUIVALENT_CLASS() property is not supported in the current language profile.

    • setDisjointWith

      void setDisjointWith(Resource cls)

      Assert that this class is disjoint with the given class. Any existing statements for disjointWith will be removed.

      Parameters:
      cls - The property that this class is disjoint with.
      Throws:
      ProfileException - If the Profile.DISJOINT_WITH() property is not supported in the current language profile.

    • addDisjointWith

      void addDisjointWith(Resource cls)

      Add a class that this class is disjoint with.

      Parameters:
      cls - A class that has no instances in common with this class.
      Throws:
      ProfileException - If the Profile.DISJOINT_WITH() property is not supported in the current language profile.

    • getDisjointWith

      OntClass getDisjointWith()

      Answer a class with which this class is disjoint. If there is more than one such class, an arbitrary selection is made.

      Returns:
      A class disjoint with this class
      Throws:
      ProfileException - If the Profile.DISJOINT_WITH() property is not supported in the current language profile.

    • listDisjointWith

      ExtendedIterator<OntClass> listDisjointWith()

      Answer an iterator over all of the classes that this class is declared to be disjoint with. Each element of the iterator will be an OntClass.

      Returns:
      An iterator over the classes disjoint with this class.
      Throws:
      ProfileException - If the Profile.DISJOINT_WITH() property is not supported in the current language profile.

    • isDisjointWith

      boolean isDisjointWith(Resource cls)

      Answer true if this class is disjoint with the given class.

      Parameters:
      cls - A class to test
      Returns:
      True if the this class is disjoint with the the given class.
      Throws:
      ProfileException - If the Profile.DISJOINT_WITH() property is not supported in the current language profile.

    • removeDisjointWith

      void removeDisjointWith(Resource cls)

      Remove the statement that this class and the given class are disjoint. If this statement is not true of the current model, nothing happens.

      Parameters:
      cls - A class that may be declared to be disjoint with this class, and which is no longer disjoint
      Throws:
      ProfileException - If the Profile.DISJOINT_WITH() property is not supported in the current language profile.

    • listDeclaredProperties

      ExtendedIterator<OntProperty> listDeclaredProperties()
      Equivalent to calling listDeclaredProperties(boolean) with default value direct = false.

    • listDeclaredProperties

      ExtendedIterator<OntProperty> listDeclaredProperties(boolean direct)

      Return an iterator over the properties associated with a frame-like view of this class. This captures an intuitive notion of the properties of a class. This can be useful in presenting an ontology class in a user interface, for example by automatically constructing a form to instantiate instances of the class. The properties in the frame-like view of the class are determined by comparing the domain of properties in this class's OntModel with the class itself. See: Presenting RDF as frames for more details.

      Note that many cases of determining whether a property is associated with a class depends on RDFS or OWL reasoning. This method may therefore return complete results only in models that have an attached reasoner.

      Parameters:
      direct - If true, restrict the properties returned to those directly associated with this class. If false, the properties of super-classes of this class will not be listed among the declared properties of this class.
      Returns:
      An iteration of the properties that are associated with this class by their domain.

    • hasDeclaredProperty

      boolean hasDeclaredProperty(Property p, boolean direct)

      Return an iteration of the properties associated with a frame-like view of this class. This captures an informal notion of the properties of a class, by looking at the domains of the properties in this class's model, and matching them to this class. A full description of the frame-like view of a class may be found in: RDF frames how-to for full details.

      Note that many cases of determining whether a property is associated with a class depends on RDFS or OWL reasoning. This method may therefore return complete results only in models that have an attached reasoner. See the

      Returns:
      An iteration of the properties that are associated with this class by their domain.

    • listInstances

      ExtendedIterator<? extends OntResource> listInstances()

      Answer an iterator over the individuals in the model that have this class among their types. Equivalent to listInstances(boolean) with an argument false.

      Returns:
      An iterator over those instances that have this class as one of the classes to which they belong

    • listInstances

      ExtendedIterator<? extends OntResource> listInstances(boolean direct)

      Answer an iterator over the individuals in the model that have this class among their types, optionally excluding sub-classes of this class.

      Parameters:
      direct - If true, only direct instances are counted (i.e. not instances of sub-classes of this class)
      Returns:
      An iterator over those instances that have this class as one of the classes to which they belong

    • createIndividual

      Individual createIndividual()

      Answer a new individual that has this class as its rdf:type

      Returns:
      A new anonymous individual that is an instance of this class

    • createIndividual

      Individual createIndividual(String uri)

      Answer a new individual that has this class as its rdf:type

      Parameters:
      uri - The URI of the new individual
      Returns:
      A new named individual that is an instance of this class

    • dropIndividual

      void dropIndividual(Resource individual)

      Remove the given individual from the set of instances that are members of this class. This is effectively equivalent to the Individual.removeOntClass(org.apache.jena.rdf.model.Resource) method, but invoked via the class resource rather than via the individual resource.

      Parameters:
      individual - A resource denoting an individual that is no longer to be a member of this class

    • isHierarchyRoot

      boolean isHierarchyRoot()

      Answer true if this class is one of the roots of the local class hierarchy. This will be true if either (i) this class has owl:Thing as a direct super-class, or (ii) it has no declared super-classes (including anonymous class expressions).

      Returns:
      True if this class is the root of the class hierarchy in the model it is attached to

    • asEnumeratedClass

      EnumeratedClass asEnumeratedClass()

      Answer a view of this class as an enumerated class

      Returns:
      This class, but viewed as an EnumeratedClass facet
      Throws:
      ConversionException - if the class cannot be converted to an enumerated class given the language profile and the current state of the underlying model.

    • asUnionClass

      UnionClass asUnionClass()

      Answer a view of this class as a union class

      Returns:
      This class, but viewed as a UnionClass facet
      Throws:
      ConversionException - if the class cannot be converted to a union class given the language profile and the current state of the underlying model.

    • asIntersectionClass

      IntersectionClass asIntersectionClass()

      Answer a view of this class as an intersection class

      Returns:
      This class, but viewed as an IntersectionClass facet
      Throws:
      ConversionException - if the class cannot be converted to an intersection class given the language profile and the current state of the underlying model.

    • asComplementClass

      ComplementClass asComplementClass()

      Answer a view of this class as a complement class

      Returns:
      This class, but viewed as a ComplementClass facet
      Throws:
      ConversionException - if the class cannot be converted to a complement class given the language profile and the current state of the underlying model.

    • asRestriction

      Restriction asRestriction()

      Answer a view of this class as a restriction class expression

      Returns:
      This class, but viewed as a Restriction facet
      Throws:
      ConversionException - if the class cannot be converted to a restriction given the language profile and the current state of the underlying model.

    • isEnumeratedClass

      boolean isEnumeratedClass()

      Answer true if this class is an enumerated class expression

      Returns:
      True if this is an enumerated class expression

    • isUnionClass

      boolean isUnionClass()

      Answer true if this class is a union class expression

      Returns:
      True if this is a union class expression

    • isIntersectionClass

      boolean isIntersectionClass()

      Answer true if this class is an intersection class expression

      Returns:
      True if this is an intersection class expression

    • isComplementClass

      boolean isComplementClass()

      Answer true if this class is a complement class expression

      Returns:
      True if this is a complement class expression

    • isRestriction

      boolean isRestriction()

      Answer true if this class is a property restriction

      Returns:
      True if this is a restriction

    • convertToEnumeratedClass

      EnumeratedClass convertToEnumeratedClass(RDFList individuals)

      Answer a view of this class as an enumeration of the given individuals.

      Parameters:
      individuals - A list of the individuals that will comprise the permitted values of this class converted to an enumeration
      Returns:
      This ontology class, converted to an enumeration of the given individuals

    • convertToIntersectionClass

      IntersectionClass convertToIntersectionClass(RDFList classes)

      Answer a view of this class as an intersection of the given classes.

      Parameters:
      classes - A list of the classes that will comprise the operands of the intersection
      Returns:
      This ontology class, converted to an intersection of the given classes

    • convertToUnionClass

      UnionClass convertToUnionClass(RDFList classes)

      Answer a view of this class as a union of the given classes.

      Parameters:
      classes - A list of the classes that will comprise the operands of the union
      Returns:
      This ontology class, converted to an union of the given classes

    • convertToComplementClass

      ComplementClass convertToComplementClass(Resource cls)

      Answer a view of this class as an complement of the given class.

      Parameters:
      cls - An ontology class that will be operand of the complement
      Returns:
      This ontology class, converted to an complement of the given class

    • convertToRestriction

      Restriction convertToRestriction(Property prop)

      Answer a view of this class as an restriction on the given property.

      Parameters:
      prop - A property this is the subject of a property restriction class expression
      Returns:
      This ontology class, converted to a restriction on the given property