Package de.learnlib.algorithm.dhc.mealy

Class MealyDHC<I,O>

java.lang.Object

de.learnlib.algorithm.dhc.mealy.MealyDHC<I,O>

All Implemented Interfaces:

AccessSequenceTransformer<I>, GlobalSuffixLearner<MealyMachine<?,I,?,O>,I,Word<O>>, GlobalSuffixLearner.GlobalSuffixLearnerMealy<I,O>, LearningAlgorithm<MealyMachine<?,I,?,O>,I,Word<O>>, LearningAlgorithm.MealyLearner<I,O>, Resumable<MealyDHCState<I,O>>, SupportsGrowingAlphabet<I>

public class MealyDHC<I,O>
extends Object
implements LearningAlgorithm.MealyLearner<I,O>, AccessSequenceTransformer<I>, GlobalSuffixLearner.GlobalSuffixLearnerMealy<I,O>, SupportsGrowingAlphabet<I>, Resumable<MealyDHCState<I,O>>

Nested Class Summary

Nested classes/interfaces inherited from interface de.learnlib.algorithm.GlobalSuffixLearner

GlobalSuffixLearner.GlobalSuffixLearnerDFA<I>, GlobalSuffixLearner.GlobalSuffixLearnerMealy<I,O>

Nested classes/interfaces inherited from interface de.learnlib.algorithm.LearningAlgorithm

LearningAlgorithm.DFALearner<I>, LearningAlgorithm.MealyLearner<I,O>, LearningAlgorithm.MooreLearner<I,O>, LearningAlgorithm.NFALearner<I>

Constructor Summary

Constructors

Constructor	Description
MealyDHC(Alphabet<I> alphabet, MembershipOracle<I,Word<O>> oracle)	Constructor, provided for backwards compatibility reasons.
MealyDHC(Alphabet<I> alphabet, MembershipOracle<I,Word<O>> oracle, GlobalSuffixFinder<? super I,? super Word<O>> suffixFinder, Collection<? extends Word<I>> initialSplitters)	Constructor.

Method Summary

Modifier and Type	Method	Description
void	addAlphabetSymbol(I symbol)
boolean	addGlobalSuffixes(Collection<? extends Word<I>> newGlobalSuffixes)	Add the provided suffixes to the collection of global suffixes.
protected boolean	addSuffixesUnchecked(Collection<? extends Word<I>> newSuffixes)
Collection<Word<I>>	getGlobalSuffixes()	Retrieves the global suffixes of this learner.
CompactMealy<I,O>	getHypothesisModel()	Returns the current hypothesis model.
boolean	refineHypothesis(DefaultQuery<I,Word<O>> ceQuery)	Triggers a refinement of the model by providing a counterexample.
void	resume(MealyDHCState<I,O> state)	Resume the datastructure from a previously suspended point in time.
void	startLearning()	Starts the model inference process, creating an initial hypothesis in the provided model object.
MealyDHCState<I,O>	suspend()	Expose the state object.
Word<I>	transformAccessSequence(Word<I> word)

Methods inherited from class java.lang.Object

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

Methods inherited from interface de.learnlib.AccessSequenceTransformer

isAccessSequence, longestASPrefix

Constructor Detail

MealyDHC

public MealyDHC(Alphabet<I> alphabet,
                MembershipOracle<I,Word<O>> oracle)

Constructor, provided for backwards compatibility reasons.

Parameters:

alphabet - the learning alphabet

oracle - the learning membership oracle

MealyDHC

public MealyDHC(Alphabet<I> alphabet,
                MembershipOracle<I,Word<O>> oracle,
                GlobalSuffixFinder<? super I,? super Word<O>> suffixFinder,
                Collection<? extends Word<I>> initialSplitters)

Constructor.

Parameters:

alphabet - the learning alphabet

oracle - the learning membership oracle

suffixFinder - the suffix finder to use for analyzing counterexamples

initialSplitters - the initial set of splitters, null or an empty collection will result in the set of splitters being initialized as the set of alphabet symbols (interpreted as Words)

Method Detail

getGlobalSuffixes

public Collection<Word<I>> getGlobalSuffixes()

Description copied from interface: GlobalSuffixLearner

Retrieves the global suffixes of this learner. Calling this method before LearningAlgorithm.startLearning() should return an empty collection.

The return value should not be modified; attempting to do so may result in an UnsupportedOperationException. It is the implementation's responsibility to ensure attempted modifications do not corrupt the learner's internal state.

Specified by:

getGlobalSuffixes in interface GlobalSuffixLearner<MealyMachine<?,I,?,O>,I,Word<O>>

Returns:

the global suffixes used by this algorithm

addGlobalSuffixes

public boolean addGlobalSuffixes(Collection<? extends Word<I>> newGlobalSuffixes)

Description copied from interface: GlobalSuffixLearner

Add the provided suffixes to the collection of global suffixes. As this method is designed to possibly trigger a refinement, it is illegal to invoke it before LearningAlgorithm.startLearning() has been called.

The implementation may choose to (but is not required to) omit suffixes which are already present (that is, manage the global suffixes as a proper set).

Specified by:

addGlobalSuffixes in interface GlobalSuffixLearner<MealyMachine<?,I,?,O>,I,Word<O>>

Parameters:

newGlobalSuffixes - the global suffixes to add

Returns:

true if a refinement was triggered by adding the global suffixes, false otherwise.

addSuffixesUnchecked

protected boolean addSuffixesUnchecked(Collection<? extends Word<I>> newSuffixes)

startLearning

public void startLearning()

Description copied from interface: LearningAlgorithm

Starts the model inference process, creating an initial hypothesis in the provided model object. Please note that it should be illegal to invoke this method twice.

Specified by:

startLearning in interface LearningAlgorithm<MealyMachine<?,I,?,O>,I,Word<O>>

refineHypothesis

public boolean refineHypothesis(DefaultQuery<I,Word<O>> ceQuery)

Description copied from interface: LearningAlgorithm

Triggers a refinement of the model by providing a counterexample. A counterexample is a query which exposes different behavior of the real SUL compared to the hypothesis. Please note that invoking this method before an initial invocation of LearningAlgorithm.startLearning() should be illegal.

Specified by:

refineHypothesis in interface LearningAlgorithm<MealyMachine<?,I,?,O>,I,Word<O>>

Parameters:

ceQuery - the query which exposes diverging behavior, as posed to the real SUL (i.e. with the SULs output).

Returns:

true if the counterexample triggered a refinement of the hypothesis, false otherwise (i.e., it was no counterexample).

getHypothesisModel

public CompactMealy<I,O> getHypothesisModel()

Description copied from interface: LearningAlgorithm

Returns the current hypothesis model.

N.B.: By the contract of this interface, the model returned by this method may not be modified (i.e., M generally should refer to an immutable interface), and its validity is retained only until the next invocation of LearningAlgorithm.refineHypothesis(DefaultQuery). If older hypotheses have to be maintained, a copy of the returned model must be made.

Please note that it should be illegal to invoke this method before an initial invocation of LearningAlgorithm.startLearning().

Specified by:

getHypothesisModel in interface LearningAlgorithm<MealyMachine<?,I,?,O>,I,Word<O>>

Returns:

the current hypothesis model.

addAlphabetSymbol

public void addAlphabetSymbol(I symbol)

Specified by:

addAlphabetSymbol in interface SupportsGrowingAlphabet<I>

suspend

public MealyDHCState<I,O> suspend()

Description copied from interface: Resumable

Expose the state object.

Specified by:

suspend in interface Resumable<I>

Returns:

The state.

resume

public void resume(MealyDHCState<I,O> state)

Description copied from interface: Resumable

Resume the datastructure from a previously suspended point in time.

Specified by:

resume in interface Resumable<I>

Parameters:

state - The learner state.

transformAccessSequence

public Word<I> transformAccessSequence(Word<I> word)

Specified by:

transformAccessSequence in interface AccessSequenceTransformer<I>