com.hp.hpl.jena.reasoner.rulesys
Class FBRuleReasoner

java.lang.Object
  com.hp.hpl.jena.reasoner.rulesys.FBRuleReasoner

All Implemented Interfaces:

Reasoner, RuleReasoner

Direct Known Subclasses:

GenericRuleReasoner, OWLFBRuleReasoner, RDFSFBRuleReasoner

public class FBRuleReasoner
extends Object
implements RuleReasoner

Rule-based reasoner interface. This is the default rule reasoner to use. It supports both forward reasoning and backward reasoning, including use of forward rules to generate and instantiate backward rules.

Version:

$Revision: 1.1 $ on $Date: 2009-06-29 08:55:38 $

Author:

Dave Reynolds

Constructor Summary

FBRuleReasoner(List<Rule> rules)
Constructor.

FBRuleReasoner(List<Rule> rules, ReasonerFactory factory)
Constructor

FBRuleReasoner(ReasonerFactory factory)
Constructor

FBRuleReasoner(ReasonerFactory factory, Resource configuration)
Constructor

Method Summary

void	addDescription(Model configSpec, Resource base) Add a configuration description for this reasoner into a partial configuration specification model.
FBRuleReasoner	addRules(List<Rule> rules) Add the given rules to the current set and answer this Reasoner.
InfGraph	bind(Graph data) Attach the reasoner to a set of RDF data to process.
Reasoner	bindSchema(Graph tbox) Precompute the implications of a schema graph.
Reasoner	bindSchema(Model tbox) Precompute the implications of a schema Model.
Graph	getBoundSchema() Answer the schema graph bound into this reasoner, or null if there isn't one.
Capabilities	getGraphCapabilities() Return the Jena Graph Capabilties that the inference graphs generated by this reasoner are expected to conform to.
Model	getReasonerCapabilities() Return a description of the capabilities of this reasoner encoded in RDF.
List<Rule>	getRules() Return the list of Rules used by this reasoner
boolean	isTraceOn() Return the state of the trace flag.If set to true then rule firings are logged out to the Log at "INFO" level.
static List<Rule>	loadRules(String fileName) Answer the list of rules loaded from the given filename.
void	setDerivationLogging(boolean logOn) Switch on/off drivation logging.
void	setParameter(Property parameter, Object value) Set a configuration parameter for the reasoner.
void	setRules(List<Rule> rules) Set (or change) the rule set that this reasoner should execute.
void	setTraceOn(boolean state) Set the state of the trace flag.
boolean	supportsProperty(Property property) Determine whether the given property is recognized and treated specially by this reasoner.
void	tablePredicate(Node predicate) Register an RDF predicate as one whose presence in a goal should force the goal to be tabled.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

FBRuleReasoner

public FBRuleReasoner(List<Rule> rules)

Constructor. This is the raw version that does not reference a ReasonerFactory and so has no capabilities description.

Parameters:

rules - a list of Rule instances which defines the ruleset to process

FBRuleReasoner

public FBRuleReasoner(ReasonerFactory factory)

Constructor

Parameters:

factory - the parent reasoner factory which is consulted to answer capability questions

FBRuleReasoner

public FBRuleReasoner(ReasonerFactory factory,
                      Resource configuration)

Constructor

Parameters:

factory - the parent reasoner factory which is consulted to answer capability questions

configuration - RDF node to configure the rule set and mode, can be null

FBRuleReasoner

public FBRuleReasoner(List<Rule> rules,
                      ReasonerFactory factory)

Constructor

Parameters:

rules - a list of Rule instances which defines the ruleset to process

factory - the parent reasoner factory which is consulted to answer capability questions

Method Detail

addRules

public FBRuleReasoner addRules(List<Rule> rules)

Add the given rules to the current set and answer this Reasoner. Provided so that the Factory can deal out reasoners with specified rulesets. There may well be a better way to arrange this. TODO review & revise

getReasonerCapabilities

public Model getReasonerCapabilities()

Return a description of the capabilities of this reasoner encoded in RDF. These capabilities may be static or may depend on configuration information supplied at construction time. May be null if there are no useful capabilities registered.

Specified by:

getReasonerCapabilities in interface Reasoner

getBoundSchema

public Graph getBoundSchema()

Answer the schema graph bound into this reasoner, or null if there isn't one. (Added mainly for testing purposes, which is why it isn't part of the Reasoner API.)

addDescription

public void addDescription(Model configSpec,
                           Resource base)

Add a configuration description for this reasoner into a partial configuration specification model.

Specified by:

addDescription in interface Reasoner

Parameters:

configSpec - a Model into which the configuration information should be placed

base - the Resource to which the configuration parameters should be added.

supportsProperty

public boolean supportsProperty(Property property)

Determine whether the given property is recognized and treated specially by this reasoner. This is a convenience packaging of a special case of getCapabilities.

Specified by:

supportsProperty in interface Reasoner

Parameters:

property - the property which we want to ask the reasoner about, given as a Node since this is part of the SPI rather than API

Returns:

true if the given property is handled specially by the reasoner.

bindSchema

public Reasoner bindSchema(Graph tbox)
                    throws ReasonerException

Precompute the implications of a schema graph. The statements in the graph will be combined with the data when the final InfGraph is created.

Specified by:

bindSchema in interface Reasoner

Parameters:

tbox - the ontology axioms or rule set encoded in RDF

Returns:

a reasoner instace which can be used to process a data graph

Throws:

ReasonerException - if the reasoner cannot be bound to a rule set in this way, for example if the underlying engine can only accept a single rule set in this way and one rule set has already been bound in of if the ruleset is illformed.

bindSchema

public Reasoner bindSchema(Model tbox)
                    throws ReasonerException

Precompute the implications of a schema Model. The statements in the graph will be combined with the data when the final InfGraph is created.

Specified by:

bindSchema in interface Reasoner

Parameters:

tbox - the ontology axioms or rule set encoded in RDF

Returns:

a reasoner instace which can be used to process a data graph

Throws:

ReasonerException - if the reasoner cannot be bound to a rule set in this way, for example if the underlying engine can only accept a single rule set in this way and one rule set has already been bound in of if the ruleset is illformed.

bind

public InfGraph bind(Graph data)
              throws ReasonerException

Attach the reasoner to a set of RDF data to process. The reasoner may already have been bound to specific rules or ontology axioms (encoded in RDF) through earlier bindRuleset calls.

Specified by:

bind in interface Reasoner

Parameters:

data - the RDF data to be processed, some reasoners may restrict the range of RDF which is legal here (e.g. syntactic restrictions in OWL).

Returns:

an inference graph through which the data+reasoner can be queried.

Throws:

ReasonerException - if the data is ill-formed according to the constraints imposed by this reasoner.

setRules

public void setRules(List<Rule> rules)

Set (or change) the rule set that this reasoner should execute.

Specified by:

setRules in interface RuleReasoner

Parameters:

rules - a list of Rule objects

getRules

public List<Rule> getRules()

Return the list of Rules used by this reasoner

Specified by:

getRules in interface RuleReasoner

Returns:

a List of Rule objects

loadRules

public static List<Rule> loadRules(String fileName)

Answer the list of rules loaded from the given filename. May throw a ReasonerException wrapping an IOException.

tablePredicate

public void tablePredicate(Node predicate)

Register an RDF predicate as one whose presence in a goal should force the goal to be tabled. This is better done directly in the rule set.

setDerivationLogging

public void setDerivationLogging(boolean logOn)

Switch on/off drivation logging. If set to true then the InfGraph created from the bind operation will start life with recording of derivations switched on. This is currently only of relevance to rule-based reasoners.

Default - false.

Specified by:

setDerivationLogging in interface Reasoner

setTraceOn

public void setTraceOn(boolean state)

Set the state of the trace flag. If set to true then rule firings are logged out to the Logger at "INFO" level.

isTraceOn

public boolean isTraceOn()

Return the state of the trace flag.If set to true then rule firings are logged out to the Log at "INFO" level.

setParameter

public void setParameter(Property parameter,
                         Object value)

Set a configuration parameter for the reasoner. The supported parameters are:

• PROPderivationLogging - set to true to enable recording all rule derivations
• PROPtraceOn - set to true to enable verbose trace information to be sent to the logger INFO channel

Specified by:

setParameter in interface Reasoner

Parameters:

parameter - the property identifying the parameter to be changed

value - the new value for the parameter, typically this is a wrapped java object like Boolean or Integer.

Throws:

IllegalParameterException - if the parameter is unknown

getGraphCapabilities

public Capabilities getGraphCapabilities()

Return the Jena Graph Capabilties that the inference graphs generated by this reasoner are expected to conform to.

Specified by:

getGraphCapabilities in interface Reasoner