Class OpenRobotsOntology

  • All Implemented Interfaces:
    IOntologyBackend, IServiceProvider

    public class OpenRobotsOntology
    extends java.lang.Object
    implements IOntologyBackend
    The OpenRobotsOntology class is the main storage backend for oro-server.
    It maps useful methods for knowledge access in a robotic context to a Jena-baked ontology.

    Amongst other feature, it offers an easy way to query the ontology with standard SPARQL requests, it can try to find resources matching a set of statements or check the consistency of the knowledge storage.

    Examples covering the various aspects of the API can be found in the Unit Tests.
    • Constructor Summary

      Constructors 
      Constructor Description
      OpenRobotsOntology()
      Constructors *
      OpenRobotsOntology​(com.hp.hpl.jena.ontology.OntModel onto)
      Constructor which takes a Jena OntModel as parameter.
      OpenRobotsOntology​(com.hp.hpl.jena.ontology.OntModel onto, java.util.Properties parameters)  
      OpenRobotsOntology​(java.util.Properties parameters)
      Constructor which takes a config file as parameter.
      The constructor first opens the ontology, then loads it into memory and eventually bounds it to Jena internal reasoner.
    • Method Summary

      All Methods Instance Methods Concrete Methods Deprecated Methods 
      Modifier and Type Method Description
      boolean add​(com.hp.hpl.jena.rdf.model.Statement statement, MemoryProfile memProfile, boolean safe)
      Adds a new statement (assertion) to the ontology.
      boolean add​(java.util.Set<com.hp.hpl.jena.rdf.model.Statement> statements, MemoryProfile memProfile, boolean safe)
      Adds a set of new statements (assertion) to the ontology.
      boolean check​(com.hp.hpl.jena.rdf.model.Statement statement)
      Checks if a statement is asserted or can be inferred from the ontology.
      boolean check​(PartialStatement statement)
      Checks if a pattern represented as a partial statement matches at least one asserted of inferred statement.
      For instance: A pattern like [?object rdf:type Bottle] would match all instances of the class Bottle. [anAgent sees ?something] would match all objects seen by instance "anAgent".
      boolean checkConsistency()
      Performs a consistency validation against the ontology.
      boolean checkConsistency​(java.util.Set<com.hp.hpl.jena.rdf.model.Statement> statements)
      Checks a set of statements (or partial statements) are not inconsistent with the current model.
      void classify()
      Classify the underlying model.
      void clear​(PartialStatement partialStmt)
      Remove all statements matching the partial statement.
      void clearEvent​(IWatcher watcher)
      Removes one specific event watcher.
      void clearEvents()
      Removes all registered event watchers for this model.
      void close()
      Closes the model
      PartialStatement createPartialStatement​(java.lang.String statement)
      This static method acts as a PartialStatement factory.
      com.hp.hpl.jena.ontology.OntProperty createProperty​(java.lang.String lex_property)
      Accessors and helpers *
      com.hp.hpl.jena.ontology.OntResource createResource​(java.lang.String lex_resource)
      Helper to create a resource attached at the current OpenRobotOntology by mapping the method to the underlying ontology model.
      This is a shortcut for OpenRobotOntology.getModel().createResource(Namespaces.format(lex_resource)).
      com.hp.hpl.jena.rdf.model.Statement createStatement​(java.lang.String statement)
      This static method acts as a Statement factory.
      java.util.Set<com.hp.hpl.jena.rdf.model.RDFNode> find​(java.lang.String varName, java.util.Set<PartialStatement> statements, java.util.Set<java.lang.String> filters)
      Tries to identify a resource given a set of partially defined statements (plus optional restrictions) about this resource.
      java.util.Set<com.hp.hpl.jena.ontology.OntClass> getClassesOf​(com.hp.hpl.jena.ontology.OntResource resource, boolean onlyDirect)  
      java.util.Set<com.hp.hpl.jena.ontology.OntResource> getInstancesOf​(com.hp.hpl.jena.ontology.OntClass type, boolean onlyDirect)  
      com.hp.hpl.jena.ontology.OntModel getModel()
      Returns the underlying Jena ontology model.
      java.util.Properties getParameters()
      Returns the current set of parameters.
      com.hp.hpl.jena.ontology.OntResource getResource​(java.lang.String lex_resource)
      Try to retrieve a resource from the ontology, based on its lexical form.
      java.util.Set<com.hp.hpl.jena.ontology.OntClass> getSubclassesOf​(com.hp.hpl.jena.ontology.OntClass type, boolean onlyDirect)  
      com.hp.hpl.jena.rdf.model.Model getSubmodel​(com.hp.hpl.jena.rdf.model.Resource node)
      Returns the set of inferred and asserted statement involving a resource as a Jena Model..
      java.util.Set<com.hp.hpl.jena.ontology.OntClass> getSuperclassesOf​(com.hp.hpl.jena.ontology.OntClass type, boolean onlyDirect)  
      java.util.Set<IWatcher.EventType> getSupportedEvents()
      Return the list of event types implemented (hence usable) by this backend.
      void list​(java.lang.String pattern)  
      java.util.Set<java.util.List<java.lang.String>> lookup​(java.lang.String id)
      Returns the set of all [id, type, label] (with type one of INSTANCE, CLASS, OBJECT_PROPERTY, DATATYPE_PROPERTY, UNDEFINED) of concepts whose labels or id match the given parameter.
      java.util.Set<java.lang.String> lookup​(java.lang.String id, ResourceType type)
      Returns the set of all id of concepts whose labels or ids match the given parameter and of the given type.
      protected void onModelChange​(java.lang.String rsName)
      This protected method is called every time the ontology model changes (ie upon addition or removal of statements in the ontology).
      java.util.Set<com.hp.hpl.jena.rdf.model.RDFNode> query​(java.lang.String key, java.lang.String query)
      Performs a SPARQL query on the OpenRobots ontology.
      For instance:
      void registerEvent​(IWatcher watcher)
      Allows to register several events providers (typically, one by underlying middleware) which in turn provide access to watchers.
      void remove​(com.hp.hpl.jena.rdf.model.Statement stmt)
      Deprecated.
      void remove​(java.util.Set<com.hp.hpl.jena.rdf.model.Statement> stmts)
      Removes a set of statements from the ontology.
      void save()  
      void save​(java.lang.String path)
      Saves the in-memory ontology model to a RDF/XML file.
      long size()
      Returns the number of statements in the model.
      void step()
      'Step' the model.
      void update​(java.util.Set<com.hp.hpl.jena.rdf.model.Statement> stmts)
      Update the value of a property.
      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    • Constructor Detail

      • OpenRobotsOntology

        public OpenRobotsOntology()
        Constructors *
      • OpenRobotsOntology

        public OpenRobotsOntology​(java.util.Properties parameters)
        Constructor which takes a config file as parameter.
        The constructor first opens the ontology, then loads it into memory and eventually bounds it to Jena internal reasoner. Thus, the instanciation of OpenRobotsOntology may take some time (several seconds, depending on the size on the ontology).

        Available options:
        • verbose = [true|false]: set it to true to get more infos from the engine.
        • ontology = PATH: the path to the OWL (or RDF) ontology to be loaded.
        • default_namespace = NAMESPACE: set the default namespace. Don't forget the trailing #!
        • short_namespaces = [true|false] (default: true): if true, the ontology engine will return resource with prefix instead of full URI, or nothing if the resource is in the default namespace.
        The file may contain other options, related to the server configuration. See OroServer. Have a look as well at the config file itself for more details.
        Parameters:
        parameters - The set of parameters, read from the server configuration file.
      • OpenRobotsOntology

        public OpenRobotsOntology​(com.hp.hpl.jena.ontology.OntModel onto)
        Constructor which takes a Jena OntModel as parameter.
        Parameters:
        onto - An already built ontology model. The OpenRobotsOntology will wrap it.
      • OpenRobotsOntology

        public OpenRobotsOntology​(com.hp.hpl.jena.ontology.OntModel onto,
                                  java.util.Properties parameters)
    • Method Detail

      • createProperty

        public com.hp.hpl.jena.ontology.OntProperty createProperty​(java.lang.String lex_property)
        Accessors and helpers *
        Specified by:
        createProperty in interface IOntologyBackend
        Parameters:
        lex_property - the lexical form of the property (eg "rdf:type").
        Returns:
        the corresponding Jena property.
        See Also:
        com.hp.hpl.jena.rdf.model.OntModel#createOntProperty(String)
      • createResource

        public com.hp.hpl.jena.ontology.OntResource createResource​(java.lang.String lex_resource)
        Description copied from interface: IOntologyBackend
        Helper to create a resource attached at the current OpenRobotOntology by mapping the method to the underlying ontology model.
        This is a shortcut for OpenRobotOntology.getModel().createResource(Namespaces.format(lex_resource)). If a resource with the same lexical form already exist, it is reused. The IOntologyBackend.getResource(String) method can be used to retrieve resource without creating a new one if it doesn't exist.
        Specified by:
        createResource in interface IOntologyBackend
        Parameters:
        lex_resource - the lexical form of the resource.
        Returns:
        the corresponding Jena resource.
        See Also:
        IOntologyBackend.getResource(String), com.hp.hpl.jena.rdf.model.OntModel#createOntResource(String)
      • createStatement

        public com.hp.hpl.jena.rdf.model.Statement createStatement​(java.lang.String statement)
                                                            throws IllegalStatementException
        Description copied from interface: IOntologyBackend
        This static method acts as a Statement factory. It does some pre-processing to convert a string to a valid statement relative to the given ontology.
        Formatting follows roughly the SPARQL syntax :
        • Literals follows the "value"^^type rule for the general case. Simple or double quotes can be used. Cf examples below.
        • Resources can be either isolated ("individual1"). It will then use the default namespace as defined in the configuration file.
        • Or prefixed with the namespace prefix ("rdf:type"),
        • Or complete URIs ("<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>"). In this case, the URI must be enclosed between < and >.

        Literals examples:
        • The boolean true can be represented either as "true"^^xsd:boolean or as true,
        • The integer 123 can be represented either as 123^^xsd:int or as 123. "123"^^xsd:int is also acceptable.
        • The double 1.23 can be represented either as 1.23^^xsd:double or as 1.23. "1.23"^^xsd:double is also acceptable.
        • User-defined dataypes can be represented with "xyz"^^<http://example.org/ns/userDatatype> or "xyz"^^oro:userDatatype.
        The unit test laas.openrobots.ontology.tests.OpenRobotsOntologyTest#testLiterals() extensively tests the various literal representation possibilities.
        Specified by:
        createStatement in interface IOntologyBackend
        Parameters:
        statement - a string containing a statement. For example, "oro:individual rdf:type oro:Class1" or "oro:individual <> oro:Class1"
        Returns:
        a new Jena statement
        Throws:
        IllegalStatementException
        See Also:
        Partial statements for partially unbound statements (like "?subject rdf:type oro:Class1")., #add(String), List of known namespace prefixes.
      • getModel

        public com.hp.hpl.jena.ontology.OntModel getModel()
        Description copied from interface: IOntologyBackend
        Returns the underlying Jena ontology model.
        Specified by:
        getModel in interface IOntologyBackend
        Returns:
        the current underlying Jena ontology model.
      • classify

        public void classify()
        Classify the underlying model. Note that this method modifies the underlying model.
      • add

        public boolean add​(java.util.Set<com.hp.hpl.jena.rdf.model.Statement> statements,
                           MemoryProfile memProfile,
                           boolean safe)
                    throws IllegalStatementException
        Description copied from interface: IOntologyBackend
        Adds a set of new statements (assertion) to the ontology. If one of the statements already exists, it won't be inserted.
        A memory profile is associated to all the statements: statements associated to MemoryProfile.LONGTERM or MemoryProfile.DEFAULT are stored and never removed from the ontology while other memory profiles allow the ontology to "forget" about certain facts after a given amount of time.
        Specified by:
        add in interface IOntologyBackend
        Parameters:
        statements - A set of statements to be inserted in the model.
        memProfile - The memory profile associated to this statement.
        safe - If true, the statement is added only if it does not
        Returns:
        True if all the statements have been actually added to the model (actually useful only in conjunction with the safe parameter enabled).
        Throws:
        IllegalStatementException - Currently only thrown if a concept is asserted to be both an instance and a class.
      • check

        public boolean check​(com.hp.hpl.jena.rdf.model.Statement statement)
        Description copied from interface: IOntologyBackend
        Checks if a statement is asserted or can be inferred from the ontology. The check is done in an open world (everything is true except if it's explicitely false). For instance, if only the following statement is asserted:
         bottle hasColor green
         
        check("bottle hasColor orange") would return true. If the two following statements are added to the ontology:
         green owl:isDifferentFrom orange
         hasColor rdf:type owl:functionalProperty
         
        then check("bottle hasColor orange") would return false.
        Specified by:
        check in interface IOntologyBackend
        Parameters:
        statement - the statement to be evaluated
        Returns:
        true if the statement is asserted in or can be inferred from the ontology
      • check

        public boolean check​(PartialStatement statement)
        Description copied from interface: IOntologyBackend
        Checks if a pattern represented as a partial statement matches at least one asserted of inferred statement.
        For instance:
        • A pattern like [?object rdf:type Bottle] would match all instances of the class Bottle.
        • [anAgent sees ?something] would match all objects seen by instance "anAgent".
        Specified by:
        check in interface IOntologyBackend
        Parameters:
        statement - the partial pattern to be evaluated
        Returns:
        true if the pattern matches at least one asserted or inferred statement of the ontology.
        See Also:
        #find(String, Vector)
      • checkConsistency

        public boolean checkConsistency()
        Description copied from interface: IOntologyBackend
        Performs a consistency validation against the ontology. Returns false if the check fails.
        Specified by:
        checkConsistency in interface IOntologyBackend
      • query

        public java.util.Set<com.hp.hpl.jena.rdf.model.RDFNode> query​(java.lang.String key,
                                                                      java.lang.String query)
                                                               throws InvalidQueryException
        Description copied from interface: IOntologyBackend
        Performs a SPARQL query on the OpenRobots ontology.
        For instance:
                IOntologyServer myOntology = new OpenRobotsOntology();
                ResultSet result =      myOntology.query(
                                                        "PREFIX rdf:  \n" +
                                                        "PREFIX owl:  \n" +
                                                        "SELECT ?instances \n" +
                                                        "WHERE { \n" +
                                                        "?instances rdf:type owl:Thing}\n");
        
         for ( ; result.hasNext() ; )
                {
                        System.out.println(result.nextSolution().toString());
                }
         
        This example would print all the instances existing in the ontology.
        Attention! Unlike other methods which take string representation of statements or resource, namespaces or namespace prefixes CAN NOT be omitted: SELECT ?instance WHERE {?instance eats bananas} won't match the same things as SELECT ?instance WHERE {?instance oro:eats oro:bananas} even if oro is the prefix of the default namespace.
        Specified by:
        query in interface IOntologyBackend
        query - A well-formed SPARQL query to perform on the ontology. PREFIX statements may be omitted if they are the standard ones (namely, owl, rdf, rdfs) or the LAAS OpenRobots ontology (oro) one.
        Returns:
        The result of the query as a set of RDFNode (either resources or literals).
        Throws:
        InvalidQueryException
        See Also:
        #queryAsXML(String)
      • find

        public java.util.Set<com.hp.hpl.jena.rdf.model.RDFNode> find​(java.lang.String varName,
                                                                     java.util.Set<PartialStatement> statements,
                                                                     java.util.Set<java.lang.String> filters)
                                                              throws InvalidQueryException
        Description copied from interface: IOntologyBackend
        Tries to identify a resource given a set of partially defined statements (plus optional restrictions) about this resource.
        Specified by:
        find in interface IOntologyBackend
        Parameters:
        varName - The name of the variable to bind, as used in the partial statements.
        statements - A set of partial statements that globaly define a search pattern
        filters - a vector of string containing the various filters to be appended to the search. The syntax is the SPARQL one (as defined here: http://www.w3.org/TR/rdf-sparql-query/#tests).
        Returns:
        a set of resources or literal (RDFNode) that match the statements.
        Throws:
        InvalidQueryException
        See Also:
        Examples of use
      • getResource

        public com.hp.hpl.jena.ontology.OntResource getResource​(java.lang.String lex_resource)
                                                         throws com.hp.hpl.jena.shared.NotFoundException
        Description copied from interface: IOntologyBackend
        Try to retrieve a resource from the ontology, based on its lexical form.
        Specified by:
        getResource in interface IOntologyBackend
        Parameters:
        lex_resource - The URI of a resource in the ontology.
        Returns:
        a RDF model containing all the statements related the the given resource.
        Throws:
        com.hp.hpl.jena.shared.NotFoundException - thrown if the resource doesn't exist in the ontology.
        See Also:
        #getSubmodel(OntResource), IOntologyBackend.createResource(String)
      • getSubmodel

        public com.hp.hpl.jena.rdf.model.Model getSubmodel​(com.hp.hpl.jena.rdf.model.Resource node)
                                                    throws com.hp.hpl.jena.shared.NotFoundException
        Description copied from interface: IOntologyBackend
        Returns the set of inferred and asserted statement involving a resource as a Jena Model..
        Specified by:
        getSubmodel in interface IOntologyBackend
        Returns:
        a RDF model containing all the statements related the the given resource.
        Throws:
        com.hp.hpl.jena.shared.NotFoundException - thrown if the resource doesn't exist in the ontology.
        See Also:
        #getSubmodel(String)
      • getSuperclassesOf

        public java.util.Set<com.hp.hpl.jena.ontology.OntClass> getSuperclassesOf​(com.hp.hpl.jena.ontology.OntClass type,
                                                                                  boolean onlyDirect)
                                                                           throws com.hp.hpl.jena.shared.NotFoundException
        Specified by:
        getSuperclassesOf in interface IOntologyBackend
        Throws:
        com.hp.hpl.jena.shared.NotFoundException
      • getSubclassesOf

        public java.util.Set<com.hp.hpl.jena.ontology.OntClass> getSubclassesOf​(com.hp.hpl.jena.ontology.OntClass type,
                                                                                boolean onlyDirect)
                                                                         throws com.hp.hpl.jena.shared.NotFoundException
        Specified by:
        getSubclassesOf in interface IOntologyBackend
        Throws:
        com.hp.hpl.jena.shared.NotFoundException
      • getInstancesOf

        public java.util.Set<com.hp.hpl.jena.ontology.OntResource> getInstancesOf​(com.hp.hpl.jena.ontology.OntClass type,
                                                                                  boolean onlyDirect)
                                                                           throws com.hp.hpl.jena.shared.NotFoundException
        Specified by:
        getInstancesOf in interface IOntologyBackend
        Throws:
        com.hp.hpl.jena.shared.NotFoundException
      • getClassesOf

        public java.util.Set<com.hp.hpl.jena.ontology.OntClass> getClassesOf​(com.hp.hpl.jena.ontology.OntResource resource,
                                                                             boolean onlyDirect)
                                                                      throws com.hp.hpl.jena.shared.NotFoundException
        Specified by:
        getClassesOf in interface IOntologyBackend
        Throws:
        com.hp.hpl.jena.shared.NotFoundException
      • getParameters

        public java.util.Properties getParameters()
        Returns the current set of parameters.
        Returns:
        the current set of parameters, reflecting the content of the configuration file.
      • clear

        public void clear​(PartialStatement partialStmt)
                   throws OntologyServerException
        Description copied from interface: IOntologyBackend
        Remove all statements matching the partial statement. Usage example:
         IOntologyServer myOntology = new OpenRobotsOntology();
         Model results = myOntology.getInfos("ns:individual1");
         
         NodeIterator types = results.listObjectsOfProperty(myOntology.createProperty("rdf:type"));
        
         for ( ; types.hasNext() ; )
         {
                System.out.println(types.nextNode().toString());
         }
         
        Specified by:
        clear in interface IOntologyBackend
        Parameters:
        partialStmt - The partial statement representing a "mask" of statements to delete.
        Throws:
        OntologyServerException
      • remove

        @Deprecated
        public void remove​(com.hp.hpl.jena.rdf.model.Statement stmt)
                    throws OntologyServerException
        Deprecated.
        Description copied from interface: IOntologyBackend
        Removes a given statement from the ontology. Does nothing if the statement doesn't exist.
        Specified by:
        remove in interface IOntologyBackend
        Parameters:
        stmt - The statement to remove from the ontology.
        Throws:
        OntologyServerException
        See Also:
        #add(Statement)
      • remove

        public void remove​(java.util.Set<com.hp.hpl.jena.rdf.model.Statement> stmts)
                    throws OntologyServerException
        Description copied from interface: IOntologyBackend
        Removes a set of statements from the ontology. It ignores statements that do not exist.
        Specified by:
        remove in interface IOntologyBackend
        Parameters:
        stmts - The statements to remove from the ontology.
        Throws:
        OntologyServerException
        See Also:
        #add(Set)
      • step

        public void step()
        Description copied from interface: IOntologyBackend
        'Step' the model. At each server main loop iteration, the 'step' method is called for each model. The model can do here its own internal homeworks.
        Specified by:
        step in interface IOntologyBackend
      • onModelChange

        protected void onModelChange​(java.lang.String rsName)
        This protected method is called every time the ontology model changes (ie upon addition or removal of statements in the ontology). It is mainly responsible for testing the various watchPatterns as provided by the set of active IWatcher against the ontology. onModelChange() relies on a caching mechanism of requests to improve performances. It remains however a serious performance bottleneck.
        Parameters:
        rsName - the name of the reified statements whose creation triggered the update. Can be null if it does not apply.
        See Also:
        onModelChange()
      • size

        public long size()
        Description copied from interface: IOntologyBackend
        Returns the number of statements in the model.
        Specified by:
        size in interface IOntologyBackend
        Returns:
        the number of statements in the model.