Package de.learnlib.filter.cache.mealy

Class MealyCacheOracle<I,O>

java.lang.Object

de.learnlib.filter.cache.mealy.MealyCacheOracle<I,O>

Type Parameters:

I - input symbol class

O - output symbol class

All Implemented Interfaces:

LearningCache<MealyMachine<?,I,?,O>,I,Word<O>>, LearningCache.MealyLearningCache<I,O>, LearningCacheOracle<MealyMachine<?,I,?,O>,I,Word<O>>, LearningCacheOracle.MealyLearningCacheOracle<I,O>, MembershipOracle<I,Word<O>>, MembershipOracle.MealyMembershipOracle<I,O>, BatchProcessor<Query<I,Word<O>>>, QueryAnswerer<I,Word<O>>, Resumable<MealyCacheOracle.MealyCacheOracleState<I,O>>, SupportsGrowingAlphabet<I>

Direct Known Subclasses:

ThreadSafeMealyCacheOracle

public class MealyCacheOracle<I,O>
extends Object
implements LearningCacheOracle.MealyLearningCacheOracle<I,O>, SupportsGrowingAlphabet<I>, Resumable<MealyCacheOracle.MealyCacheOracleState<I,O>>

Mealy cache. This cache is implemented as a membership oracle: upon construction, it is provided with a delegate oracle. Queries that can be answered from the cache are answered directly, others are forwarded to the delegate oracle. When the delegate oracle has finished processing these remaining queries, the results are incorporated into the cache.

This oracle additionally enables the user to define a Mealy-style prefix-closure filter: a Mapping from output symbols to output symbols may be provided, with the following semantics: If in an output word a symbol for which the given mapping has a non-null value is encountered, all symbols after this symbol are replaced by the respective value. The rationale behind this is that the concrete error message (key in the mapping) is still reflected in the learned model, it is forced to result in a sink state with only a single repeating output symbol (value in the mapping).

Note: this implementation is not thread-safe. If you require a cache that is usable in a parallel environment. use the ThreadSafeMealyCacheOracle (or rather the ThreadSafeMealyCaches factory) from the learnlib-parallelism artifact.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	MealyCacheOracle.MealyCacheOracleState<I,O>

Nested classes/interfaces inherited from interface de.learnlib.filter.cache.LearningCache

LearningCache.DFALearningCache<I>, LearningCache.MealyLearningCache<I,O>, LearningCache.MooreLearningCache<I,O>

Nested classes/interfaces inherited from interface de.learnlib.filter.cache.LearningCacheOracle

LearningCacheOracle.DFALearningCacheOracle<I>, LearningCacheOracle.MealyLearningCacheOracle<I,O>, LearningCacheOracle.MooreLearningCacheOracle<I,O>

Nested classes/interfaces inherited from interface de.learnlib.oracle.MembershipOracle

MembershipOracle.DFAMembershipOracle<I>, MembershipOracle.MealyMembershipOracle<I,O>, MembershipOracle.MooreMembershipOracle<I,O>

Method Summary

Modifier and Type	Method	Description
void	addAlphabetSymbol(I symbol)
EquivalenceOracle.MealyEquivalenceOracle<I,O>	createCacheConsistencyTest()	Creates a cache consistency test.
void	processQueries(Collection<? extends Query<I,Word<O>>> queries)	Processes the specified collection of queries.
void	resume(MealyCacheOracle.MealyCacheOracleState<I,O> state)	Resume the datastructure from a previously suspended point in time.
MealyCacheOracle.MealyCacheOracleState<I,O>	suspend()	Expose the state object.

Methods inherited from class java.lang.Object

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

Methods inherited from interface de.learnlib.oracle.MembershipOracle

answerQuery, answerQuery, asOracle, processBatch, processQuery

Method Detail

createCacheConsistencyTest

public EquivalenceOracle.MealyEquivalenceOracle<I,O> createCacheConsistencyTest()

Description copied from interface: LearningCache

Creates a cache consistency test. A cache consistency test is an equivalence oracle which checks a given hypothesis against the current contents of the cache. Hence, no queries are posed to the underlying system.

The created cache consistency test is backed by the cache contents. This method does not need to be invoked repeatedly when the cache contents change.

Specified by:

createCacheConsistencyTest in interface LearningCache<MealyMachine<?,I,?,O>,I,Word<O>>

Returns:

a cache consistency test for the contents of this cache

processQueries

public void processQueries(Collection<? extends Query<I,Word<O>>> queries)

Description copied from interface: MembershipOracle

Processes the specified collection of queries. When this method returns, each of the contained queries Query.answer(Object) method should have been called with an argument reflecting the SUL response to the respective query.

Specified by:

processQueries in interface MembershipOracle<I,O>

Parameters:

queries - the queries to process

See Also:

Query.answer(Object)

addAlphabetSymbol

public void addAlphabetSymbol(I symbol)

Specified by:

addAlphabetSymbol in interface SupportsGrowingAlphabet<I>

suspend

public MealyCacheOracle.MealyCacheOracleState<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(MealyCacheOracle.MealyCacheOracleState<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.