org.deri.iris.evaluation
Interface IEvaluationStrategy

All Known Implementing Classes:

OLDTEvaluationStrategy, OptimisedProgramStrategyAdaptor, SLDNFEvaluationStrategy, StratifiedBottomUpEvaluationStrategy, WellFoundedEvaluationStrategy

public interface IEvaluationStrategy

Interface for all evaluation strategy implementations.

Method Summary

IRelation

evaluateQuery(IQuery query, List<IVariable> outputVariables) Evaluate a query and optionally return the variable bindings.

Method Detail

evaluateQuery

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

Evaluate a query and optionally return the variable bindings.

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.