org.eclipse.incquery.runtime.matchers.planning.helpers

Class TypeHelper

java.lang.Object

org.eclipse.incquery.runtime.matchers.planning.helpers.TypeHelper

public class TypeHelper
extends java.lang.Object

Author:

Gabor Bergmann

Constructor Summary

Constructors

Constructor and Description
TypeHelper()

Method Summary

Modifier and Type	Method and Description
static java.util.Set<TypeJudgement>	getDirectJudgements(java.util.Set<PConstraint> constraints, IQueryMetaContext context) Gets direct judgements reported by constraints.
static java.util.Map<PVariable,java.util.Set<TypeJudgement>>	inferUnaryTypes(java.util.Set<PConstraint> constraints, IQueryMetaContext context) Infers unary type information for variables, based on the given constraints.
static java.util.Set<TypeJudgement>	subsumeTypes(java.util.Set<TypeJudgement> subsumableTypes, java.util.Set<TypeJudgement> subsumingTypes, IQueryMetaContext context) Calculates a remainder set of types from a larger set, that are not subsumed by a given set of subsuming types.
static java.util.Set<TypeJudgement>	typeClosure(java.util.Set<TypeJudgement> typesToClose, IQueryMetaContext context) Calculates the closure of a set of type judgements, with respect to supertyping.

Methods inherited from class java.lang.Object

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

Constructor Detail

TypeHelper

public TypeHelper()

Method Detail

inferUnaryTypes

public static java.util.Map<PVariable,java.util.Set<TypeJudgement>> inferUnaryTypes(java.util.Set<PConstraint> constraints,
                                                                                    IQueryMetaContext context)

Infers unary type information for variables, based on the given constraints. Subsumptions are not taken into account.

Parameters:

constraints - the set of constraints to extract type info from

getDirectJudgements

public static java.util.Set<TypeJudgement> getDirectJudgements(java.util.Set<PConstraint> constraints,
                                                               IQueryMetaContext context)

Gets direct judgements reported by constraints. No closure is applied yet.

typeClosure

public static java.util.Set<TypeJudgement> typeClosure(java.util.Set<TypeJudgement> typesToClose,
                                                       IQueryMetaContext context)

Calculates the closure of a set of type judgements, with respect to supertyping.

Returns:

the set of all type judgements in typesToClose and all their direct and indirect supertypes

subsumeTypes

public static java.util.Set<TypeJudgement> subsumeTypes(java.util.Set<TypeJudgement> subsumableTypes,
                                                        java.util.Set<TypeJudgement> subsumingTypes,
                                                        IQueryMetaContext context)

Calculates a remainder set of types from a larger set, that are not subsumed by a given set of subsuming types.

Parameters:

subsumableTypes - a set of types from which some may be implied by the subsuming types

subsumingTypes - a set of types that may imply some of the subsuming types

Returns:

the collection of types in subsumableTypes that are NOT identical to or supertypes of any type in subsumingTypes.