ModelDataSource Class Reference

A data source backed by a Jena model. More...

Inheritance diagram for ModelDataSource:

Collaboration diagram for ModelDataSource:

Public Member Functions
	ModelDataSource (Model model)
boolean	canDescribe (String absoluteIRI)
	Indicates whether this data source may have some information about a given IRI. More...
Model	describeResource (String resourceURI)
	Returns a subgraph of the data source describing one resource. More...
Map< Property, Integer >	getHighIndegreeProperties (String resourceURI)
	If describeResource(String) omits properties of high indegree, then those properties must be returned here with the count of arcs. More...
Map< Property, Integer >	getHighOutdegreeProperties (String resourceURI)
	If describeResource(String) omits properties of high outdegree, then those properties must be returned here with the count of arcs. More...
Model	listPropertyValues (String resourceURI, Property property, boolean isInverse)
	Returns a subgraph of the data source. More...
List< Resource >	getIndex ()
	A list of IRI resources described in this data source. More...
de.fuberlin.wiwiss.pubby.util.AutocompleteEngine< SearchRecord >	getLabelIndex ()
Model	describeResource (String absoluteIRI, String language)
	Returns a subgraph of the data source describing one resource. More...

Static Public Attributes
static final int	MAX_INDEX_SIZE = 1000000

Private Attributes
Model	model
AutocompleteEngine< SearchRecord >	engine

Detailed Description

A data source backed by a Jena model.

Constructor & Destructor Documentation

ModelDataSource()

ModelDataSource

(

Model

model

)

                                            {
                this.model = model;
        }

References ModelDataSource.model.

Member Function Documentation

canDescribe()

boolean canDescribe

(

String

absoluteIRI

)

Indicates whether this data source may have some information about a given IRI.

If this is false, a client should not bother to call describeResource(String). This method is to allow for optimizations and should respond very fast.

It is also used by the UI to decide whether a click on a resource should go to a Pubby page (if true) or out to the Web (if false).

Parameters

absoluteIRI

The IRI of a resource to be described

Returns

true if this data source might have something about it

Implements DataSource.

                                                       {
                return true;
        }

describeResource() [1/2]

Model describeResource	(	String	absoluteIRI,
		String	language
	)

Returns a subgraph of the data source describing one resource.

This should include both incoming and outgoing triples. However, it should exclude outgoing arcs where the property is a high-outdegree property, and it should exclude incoming arcs where the property is a high-indegree property. If labels for other resources are included in the result, then they will be used.

Parameters

absoluteIRI

The IRI of the resource to be described

Returns

A subgraph of the data source describing the resource.

Implements DataSource.

                                                                           {
                // TODO Auto-generated method stub
                return null;
        }

describeResource() [2/2]

Model describeResource

(

String

absoluteIRI

)

Returns a subgraph of the data source describing one resource.

This should include both incoming and outgoing triples. However, it should exclude outgoing arcs where the property is a high-outdegree property, and it should exclude incoming arcs where the property is a high-indegree property. If labels for other resources are included in the result, then they will be used.

Parameters

absoluteIRI

The IRI of the resource to be described

Returns

A subgraph of the data source describing the resource.

Implements DataSource.

                                                          {
                Resource r = ResourceFactory.createResource(resourceURI);
                if (model.contains(r, null, (RDFNode) null) || model.contains(null, null, r)) {
                        return model;
                }
                return ModelUtil.EMPTY_MODEL;
        }

References ModelUtil.EMPTY_MODEL, and ModelDataSource.model.

getHighIndegreeProperties()

Map<Property, Integer> getHighIndegreeProperties

(

String

resourceIRI

)

If describeResource(String) omits properties of high indegree, then those properties must be returned here with the count of arcs.

If high-indegree properties are not omitted, or the resource doesn't have any, then an empty map or null may be returned. Entries with value 0 will be ignored.

Parameters

resourceIRI

The IRI of the resource to be described

Returns

A map containing high-indegree properties with number of arcs for the resource

Implements DataSource.

                                                                                    {
                return null;
        }

getHighOutdegreeProperties()

Map<Property, Integer> getHighOutdegreeProperties

(

String

resourceIRI

)

If describeResource(String) omits properties of high outdegree, then those properties must be returned here with the count of arcs.

If high-outdegree properties are not omitted, or the resource doesn't have any, then an empty map or null may be returned. Entries with value 0 will be ignored.

Parameters

resourceIRI

The IRI of the resource to be described

Returns

A map containing high-outdegree properties with number of arcs for the resource

Implements DataSource.

                                                                                     {
                return null;
        }

getIndex()

List<Resource> getIndex

(

)

A list of IRI resources described in this data source.

Ordering is implementation-defined. Usually a reasonable limit should be applied to the number of resources returned.

Implements DataSource.

                                         {
                List<Resource> result = new ArrayList<Resource>();
                ResIterator subjects = model.listSubjects();
                while (subjects.hasNext() && result.size() < DataSource.MAX_INDEX_SIZE) {
                        Resource r = subjects.next();
                        if (r.isAnon()) continue;
                        result.add(r);
                }
                NodeIterator objects = model.listObjects();
                while (objects.hasNext() && result.size() < DataSource.MAX_INDEX_SIZE) {
                        RDFNode o = objects.next();
                        if (!o.isURIResource()) continue;
                        result.add(o.asResource());
                }
                return result;
        }

References DataSource.MAX_INDEX_SIZE, and ModelDataSource.model.

getLabelIndex()

de.fuberlin.wiwiss.pubby.util.AutocompleteEngine<SearchRecord> getLabelIndex

(

)

Implements DataSource.

                                                                                              {
                System.out.println("ModelDataSource: Get Label Index!!!!");
                if(engine==null) {
                        engine=SearchIndexInstance.getInstance();
                        System.out.println("Building Label Index....");
                        List<Resource> result = new ArrayList<Resource>();
                        ResIterator subjects = model.listSubjects();
                        int i=0;
                        while (subjects.hasNext() && result.size() < DataSource.MAX_INDEX_SIZE) {
                                Resource r = subjects.next();
                                if (r.isAnon()) continue;
                                StmtIterator st = r.listProperties(RDFS.label);
                                while(st.hasNext()) {
                                        Literal lit=st.next().getObject().asLiteral();
                                        String label=lit.getString();
                                        engine.add(new SearchRecord(label,r));
                                }
                                i++;
                        }
                        System.out.println("Added "+i+" Labels to Index");
                }
                return engine;
        }

References ModelDataSource.engine, SearchIndexInstance.getInstance(), DataSource.MAX_INDEX_SIZE, and ModelDataSource.model.

listPropertyValues()

Model listPropertyValues	(	String	resourceIRI,
		Property	property,
		boolean	isInverse
	)

Returns a subgraph of the data source.

It lists the values of a particular property of a particular resource. Where values are blank nodes, a complete description of these anonymous resources must be included.

Parameters

resourceIRI	The resource to be examined
property	The property we're interested in
isInverse	Are we interested in outgoing arcs (false) or incoming (true)?

Returns

A subgraph of the data source.

Implements DataSource.

                                           {
                return model;
        }

References ModelDataSource.model.

Member Data Documentation

engine

AutocompleteEngine<SearchRecord> engine

private

Referenced by ModelDataSource.getLabelIndex().

MAX_INDEX_SIZE

final int MAX_INDEX_SIZE = 1000000

staticinherited

Referenced by ModelDataSource.getIndex(), RemoteSPARQLDataSource.getIndex(), ModelDataSource.getLabelIndex(), and RemoteSPARQLDataSource.getLabelIndex().

model

Model model

private

Referenced by ModelDataSource.describeResource(), ModelDataSource.getIndex(), ModelDataSource.getLabelIndex(), ModelDataSource.listPropertyValues(), and ModelDataSource.ModelDataSource().