Package de.learnlib.filter.cache.sul

Class SULCache<I,O>

java.lang.Object

de.learnlib.filter.cache.sul.SULCache<I,O>

Type Parameters:

I - input symbol type

O - output symbol type

All Implemented Interfaces:

LearningCache<net.automatalib.automaton.transducer.MealyMachine<?,I,?,O>,I,net.automatalib.word.Word<O>>, LearningCache.MealyLearningCache<I,O>, Resumable<de.learnlib.filter.cache.sul.AbstractSULCache.SULCacheState<I,O>>, SUL<I,O>, net.automatalib.alphabet.SupportsGrowingAlphabet<I>

Direct Known Subclasses:

ThreadSafeSULCache

public class SULCache<I,O>
extends Object

A cache to be used with a SUL.

Because on a SUL, a query is executed step-by-step, it is impossible to determine in advance whether the cached information is sufficient to answer the complete query. However, in general it is undesired to execute any actions on the underlying SUL as long as the requested information can be provided from the cache.

This class therefore defers any real execution to the point where the cached information is definitely insufficient; if such a point is not reached before a call to SUL.post() is made, the underlying SUL is not queried.

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

Nested Class Summary

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

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

Method Summary

Modifier and Type	Method	Description
void	addAlphabetSymbol(I symbol)
boolean	canFork()
EquivalenceOracle.MealyEquivalenceOracle<I,O>	createCacheConsistencyTest()	Creates a cache consistency test.
SUL<I,O>	fork()
void	post()
void	pre()
void	resume(C state)
int	size()
O	step(I in)
C	suspend()

Methods inherited from class java.lang.Object

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

Method Detail

pre

public void pre()

Specified by:

pre in interface SUL<I,O>

post

public void post()

Specified by:

post in interface SUL<I,O>

step

public O step(I in)

Specified by:

step in interface SUL<I,O>

canFork

public boolean canFork()

Specified by:

canFork in interface SUL<I,O>

fork

public SUL<I,O> fork()

Specified by:

fork in interface SUL<I,O>

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<I,O,C extends de.learnlib.filter.cache.sul.AbstractSULCache.SULCacheState<I,O>>

Returns:

a cache consistency test for the contents of this cache

addAlphabetSymbol

public void addAlphabetSymbol(I symbol)

Specified by:

addAlphabetSymbol in interface net.automatalib.alphabet.SupportsGrowingAlphabet<I>

suspend

public C suspend()

Specified by:

suspend in interface Resumable<I>

resume

public void resume(C state)

Specified by:

resume in interface Resumable<I>

size

public int size()