Module de.learnlib.oracle.equivalence
Package de.learnlib.oracle.equivalence

Class CExFirstOracle<A extends Output<I,D>,I,D>

java.lang.Object
de.learnlib.oracle.equivalence.CExFirstOracle<A,I,D>
Type Parameters:
A - automaton type
I - input symbol type
D - output domain type
All Implemented Interfaces:
BlackBoxOracle<A,I,D>, EquivalenceOracle<A,I,D>, InclusionOracle<A,I,D>
Direct Known Subclasses:
DFACExFirstOracle, MealyCExFirstOracle
public class CExFirstOracle<A extends Output<I,D>,I,D> extends Object implements BlackBoxOracle<A,I,D>
The strategy of this black-box oracle is to first try out a property, to see if it can be disproved. If it can not be disproved it tries the same property to find a counter example to the hypothesis, before continuing with the next property.

This implementation may be used when refining a hypothesis is inexpensive compared to disproving propertyOracles.

See Also:

  • Constructor Details

    • CExFirstOracle

      public CExFirstOracle()

    • CExFirstOracle

      public CExFirstOracle(PropertyOracle<I,? super A,?,D> propertyOracle)

    • CExFirstOracle

      public CExFirstOracle(Collection<? extends PropertyOracle<I,? super A,?,D>> propertyOracles)

  • Method Details

    • getPropertyOracles

      public List<PropertyOracle<I,? super A,?,D>> getPropertyOracles()
      Description copied from interface: BlackBoxOracle
      Returns the property oracles that this black-box oracle uses to evaluate properties.
      Specified by:
      getPropertyOracles in interface BlackBoxOracle<A extends Output<I,D>,I,D>
      Returns:
      the property oracles.

    • findCounterExample

      public @Nullable DefaultQuery<I,D> 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 Output<I,D>,I,D>
      Parameters:
      hypothesis - the conjecture
      inputs - the set of inputs to consider, this should be a subset of the input alphabet of the provided hypothesis
      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.