org.deri.iris.evaluation.topdown.sldnf
Class SLDNFEvaluationStrategy

java.lang.Object
  org.deri.iris.evaluation.topdown.sldnf.SLDNFEvaluationStrategy

All Implemented Interfaces:

IEvaluationStrategy

public class SLDNFEvaluationStrategy
extends Object
implements IEvaluationStrategy

Implementation of the SLDNF evaluation strategy. For details see 'Deduktive Datenbanken' by Cremers, Griefahn and Hinze (ISBN 978-3528047009).

Author:

gigi

Field Summary

protected Configuration	mConfiguration
protected IFacts	mFacts
protected List<IRule>	mRules

Constructor Summary

SLDNFEvaluationStrategy(IFacts facts, List<IRule> rules, Configuration configuration)
Constructor

Method Summary

IRelation

evaluateQuery(IQuery query, List<IVariable> outputVariables) Evaluate the query

Methods inherited from class java.lang.Object

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

Field Detail

mFacts

protected final IFacts mFacts

mRules

protected final List<IRule> mRules

mConfiguration

protected final Configuration mConfiguration

Constructor Detail

SLDNFEvaluationStrategy

public SLDNFEvaluationStrategy(IFacts facts,
                               List<IRule> rules,
                               Configuration configuration)
                        throws EvaluationException

Constructor

Parameters:

facts - Given facts.

rules - Given rules.

configuration - Configuration

Throws:

EvaluationException

Method Detail

evaluateQuery

public IRelation evaluateQuery(IQuery query,
                               List<IVariable> outputVariables)
                        throws ProgramNotStratifiedException,
                               RuleUnsafeException,
                               EvaluationException

Evaluate the query

Specified by:

evaluateQuery in interface IEvaluationStrategy

Parameters:

query - The query to evaluate.

outputVariables - If this is not null, it will be filled with the variable bindings of the result relation, i.e. there will be one variable instance for each term (in one row) of the results set

Returns:

The relation of results.

Throws:

ProgramNotStratifiedException - If the program (knowledge-base)can not be stratified

RuleUnsafeException - If the program (knowledge-base) contains an unsafe rule.

EvaluationException - If the evaluation fails for any other reason.