/*
* $Id: VirtInfGraph.java,v 1.1.4.4 2012/03/08 12:55:00 source Exp $
*
* This file is part of the OpenLink Software Virtuoso Open-Source (VOS)
* project.
*
* Copyright (C) 1998-2014 OpenLink Software
*
* This project 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; only version 2 of the License, dated June 1991.
*
* 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, write to the Free Software Foundation, Inc.,
* 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
*/
package virtuoso.jena.driver;
//import java.sql.*;
import java.util.*;
import com.hp.hpl.jena.graph.*;
import com.hp.hpl.jena.graph.compose.MultiUnion;
import com.hp.hpl.jena.graph.impl.*;
import com.hp.hpl.jena.shared.*;
import com.hp.hpl.jena.util.iterator.*;
import com.hp.hpl.jena.datatypes.*;
import com.hp.hpl.jena.rdf.model.*;
import com.hp.hpl.jena.reasoner.*;
public class VirtInfGraph extends VirtGraph implements InfGraph
{
protected boolean recordDerivations;
public VirtInfGraph(String _ruleSet, boolean useSameAs, String graphName)
{
super(graphName);
setRuleSet(_ruleSet);
setSameAs(useSameAs);
}
public VirtInfGraph(String _ruleSet, boolean useSameAs, String graphName,
String url_hostlist, String user, String password)
{
super(graphName, url_hostlist, user, password);
setRuleSet(_ruleSet);
setSameAs(useSameAs);
}
public VirtInfGraph(String _ruleSet, boolean useSameAs, String graphName,
String url_hostlist, String user, String password,
boolean roundrobin)
{
super(graphName, url_hostlist, user, password, roundrobin);
setRuleSet(_ruleSet);
setSameAs(useSameAs);
}
/**
* Return the raw RDF data Graph being processed (i.e. the argument
* to the Reasonder.bind call that created this InfGraph).
*/
public Graph getRawGraph()
{
VirtGraph g = new VirtGraph(getGraphName(), getGraphUrl(), getGraphUser(),
getGraphPassword(), roundrobin);
return g;
}
/**
* Return the Reasoner which is being used to answer queries to this graph.
*/
public Reasoner getReasoner()
{
return null; //??TODO
}
/**
* Replace the underlying data graph for this inference graph and start any
* inferences over again. This is primarily using in setting up ontology imports
* processing to allow an imports multiunion graph to be inserted between the
* inference graph and the raw data, before processing.
* @param data the new raw data graph
*/
public void rebind(Graph data)
{
}
/**
* Cause the inference graph to reconsult the underlying graph to take
* into account changes. Normally changes are made through the InfGraph's add and
* remove calls are will be handled appropriately. However, in some cases changes
* are made "behind the InfGraph's back" and this forces a full reconsult of
* the changed data.
*/
public void rebind()
{
}
/**
* Perform any initial processing and caching. This call is optional. Most
* engines either have negligable set up work or will perform an implicit
* "prepare" if necessary. The call is provided for those occasions where
* substantial preparation work is possible (e.g. running a forward chaining
* rule system) and where an application might wish greater control over when
* this prepration is done.
*/
public void prepare()
{
}
/**
* Reset any internal caches. Some systems, such as the tabled backchainer,
* retain information after each query. A reset will wipe this information preventing
* unbounded memory use at the expense of more expensive future queries. A reset
* does not cause the raw data to be reconsulted and so is less expensive than a rebind.
*/
public void reset()
{
}
/**
* Test a global boolean property of the graph. This might included
* properties like consistency, OWLSyntacticValidity etc.
* It remains to be seen what level of generality is needed here. We could
* replace this by a small number of specific tests for common concepts.
* @param property the URI of the property to be tested
* @return a Node giving the value of the global property, this may
* be a boolean literal, some other literal value (e.g. a size).
*/
public Node getGlobalProperty(Node property)
{
throw new ReasonerException("Global property not implemented: " + property);
}
/**
* A convenience version of getGlobalProperty which can only return
* a boolean result.
*/
public boolean testGlobalProperty(Node property)
{
Node resultNode = getGlobalProperty(property);
if (resultNode.isLiteral()) {
Object result = resultNode.getLiteralValue();
if (result instanceof Boolean) {
return ((Boolean)result).booleanValue();
}
}
throw new ReasonerException("Global property test returned non-boolean value" +
"\nTest was: " + property +
"\nResult was: " + resultNode);
}
/**
* Test the consistency of the bound data. This normally tests
* the validity of the bound instance data against the bound
* schema data.
* @return a ValidityReport structure
*/
public ValidityReport validate()
{
checkOpen();
return new StandardValidityReport();
}
/**
* An extension of the Graph.find interface which allows the caller to
* encode complex expressions in RDF and then refer to those expressions
* within the query triple. For example, one might encode a class expression
* and then ask if there are any instances of this class expression in the
* InfGraph.
* @param subject the subject Node of the query triple, may be a Node in
* the graph or a node in the parameter micro-graph or null
* @param property the property to be retrieved or null
* @param object the object Node of the query triple, may be a Node in
* the graph or a node in the parameter micro-graph.
* @param param a small graph encoding an expression which the subject and/or
* object nodes refer.
*/
public ExtendedIterator<Triple> find(Node subject, Node property, Node object, Graph param)
{
return cloneWithPremises(param).find(subject, property, object);
}
/**
* Return a new inference graph which is a clone of the current graph
* together with an additional set of data premises. The default
* implementation loses ALL partial deductions so far. Some subclasses
* may be able to a more efficient job.
*/
public Graph cloneWithPremises(Graph premises) {
MultiUnion union = new MultiUnion();
union.addGraph( this );
union.setBaseGraph( this );
union.addGraph( premises );
return union;
}
/**
* Switch on/off drivation logging
*/
public void setDerivationLogging(boolean logOn)
{
recordDerivations = logOn;
}
/**
* Return the derivation of the given triple (which is the result of
* some previous find operation).
* Not all reasoneers will support derivations.
* @return an iterator over Derivation records or null if there is no derivation information
* available for this triple.
*/
public Iterator<Derivation> getDerivation(Triple triple) {
return null;
}
/**
* Returns a derivations graph. The rule reasoners typically create a
* graph containing those triples added to the base graph due to rule firings.
* In some applications it can useful to be able to access those deductions
* directly, without seeing the raw data which triggered them. In particular,
* this allows the forward rules to be used as if they were rewrite transformation
* rules.
* @return the deductions graph, if relevant for this class of inference
* engine or null if not.
*/
public Graph getDeductionsGraph()
{
return null;
}
}