de.uka.ilkd.key.strategy.feature

Class BinaryFeature

java.lang.Object

de.uka.ilkd.key.strategy.feature.BinaryFeature

All Implemented Interfaces:

Feature

Direct Known Subclasses:

AllowedCutPositionFeature, BinaryTacletAppFeature, CompareCostsFeature, ContainsLabelFeature, ContainsLabelNameFeature, CutHeapObjectsFeature, DependencyContractFeature, DirectlyBelowFeature, FocusInAntecFeature, FormulaAddedByRuleFeature, ImplicitCastNecessary, NotBelowBinderFeature, NotBelowQuantifierFeature, NotInScopeOfModalityFeature, SeqContainsExecutableCodeFeature, SortComparisonFeature, SplittableQuantifiedFormulaFeature, ThrownExceptionFeature

public abstract class BinaryFeature
extends java.lang.Object
implements Feature

Abstract superclass for features that have either zero cost or top cost.

Field Summary

Fields

Modifier and Type	Field and Description
static RuleAppCost	TOP_COST Constant that represents the boolean value false
static RuleAppCost	ZERO_COST Constant that represents the boolean value true

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	BinaryFeature()

Method Summary

Modifier and Type	Method and Description
RuleAppCost	computeCost(RuleApp app, PosInOccurrence pos, Goal goal) Evaluate the cost of a RuleApp.
protected abstract boolean	filter(RuleApp app, PosInOccurrence pos, Goal goal) Compute whether the result of the feature is zero (true) or infinity (false)

Methods inherited from class java.lang.Object

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

Field Detail

ZERO_COST

public static final RuleAppCost ZERO_COST

Constant that represents the boolean value true

TOP_COST

public static final RuleAppCost TOP_COST

Constant that represents the boolean value false

Constructor Detail

BinaryFeature

protected BinaryFeature()

Method Detail

computeCost

public RuleAppCost computeCost(RuleApp app,
                               PosInOccurrence pos,
                               Goal goal)

Description copied from interface: Feature

Evaluate the cost of a RuleApp.

Specified by:

computeCost in interface Feature

Parameters:

app - the RuleApp

pos - position where app is to be applied

goal - the goal on which app is to be applied

Returns:

the cost of the rule application expressed as a RuleAppCost object. TopRuleAppCost.INSTANCE indicates that the rule shall not be applied at all (it is discarded by the strategy).

filter

protected abstract boolean filter(RuleApp app,
                                  PosInOccurrence pos,
                                  Goal goal)

Compute whether the result of the feature is zero (true) or infinity (false)

Parameters:

app - the RuleApp

pos - position where app is to be applied

goal - the goal on which app is to be applied

Returns:

true iff the the result of the feature is supposed to be zero.