de.learnlib.eqtests.basic

Class WMethodEQOracle<A extends UniversalDeterministicAutomaton<?,I,?,?,?> & Output<I,O>,I,O>

java.lang.Object

de.learnlib.eqtests.basic.WMethodEQOracle<A,I,O>

Type Parameters:

A - automaton class

I - input symbol class

O - output class

All Implemented Interfaces:

EquivalenceOracle<A,I,O>

Direct Known Subclasses:

WMethodEQOracle.DFAWMethodEQOracle, WMethodEQOracle.MealyWMethodEQOracle

public class WMethodEQOracle<A extends UniversalDeterministicAutomaton<?,I,?,?,?> & Output<I,O>,I,O>
extends Object
implements EquivalenceOracle<A,I,O>

Implements an equivalence test by applying the W-method test on the given hypothesis automaton, as described in "Testing software design modelled by finite state machines" by T.S. Chow.

Author:

Malte Isberner

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	WMethodEQOracle.DFAWMethodEQOracle<I>
static class	WMethodEQOracle.MealyWMethodEQOracle<I,O>

Nested classes/interfaces inherited from interface de.learnlib.api.EquivalenceOracle

EquivalenceOracle.DFAEquivalenceOracle<I>, EquivalenceOracle.MealyEquivalenceOracle<I,O>

Constructor Summary

Constructors

Constructor and Description
WMethodEQOracle(int maxDepth, MembershipOracle<I,O> sulOracle) Constructor.

Method Summary

Methods

Modifier and Type	Method and Description
DefaultQuery<I,O>	findCounterExample(A hypothesis, Collection<? extends I> inputs) Searches for a counterexample disproving the subjected hypothesis.

Methods inherited from class java.lang.Object

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

Constructor Detail

WMethodEQOracle

public WMethodEQOracle(int maxDepth,
               MembershipOracle<I,O> sulOracle)

Constructor.

Parameters:

maxDepth - the maximum length of the "middle" part of the test cases

sulOracle - interface to the system under learning

Method Detail

findCounterExample

public DefaultQuery<I,O> findCounterExample(A hypothesis,
                                   Collection<? extends I> inputs)

Description copied from interface: EquivalenceOracle

Searches for a counterexample disproving the subjected hypothesis. A counterexample is query which, when performed on the SUL, yields a different output than what was predicted by the hypothesis. If no counterexample could be found (this does not necessarily mean that none exists), null is returned.

Specified by:

findCounterExample in interface EquivalenceOracle<A extends UniversalDeterministicAutomaton<?,I,?,?,?> & Output<I,O>,I,O>

Parameters:

hypothesis - the conjecture

inputs - the set of inputs to consider

Returns:

a query exposing different behavior, or null if no counterexample could be found. In case a non-null value is returned, the output field in the DefaultQuery contains the SUL output for the respective query.