org.eclipse.xtext.xbase.typesystem.computation

Class CollectionLiteralsTypeComputer

java.lang.Object

org.eclipse.xtext.xbase.typesystem.computation.AbstractTypeComputer

org.eclipse.xtext.xbase.typesystem.computation.CollectionLiteralsTypeComputer

public class CollectionLiteralsTypeComputer
extends AbstractTypeComputer

Utility that helps to compute the type for collection literals.

Since:

2.8

Author:

Sebastian Zarnekow - Initial contribution and API

Constructor Summary

Constructors

Constructor and Description
CollectionLiteralsTypeComputer()

Method Summary

Methods

Modifier and Type	Method and Description
protected void	computeArrayLiteralType(XListLiteral literal, LightweightTypeReference expectedArrayType, ITypeExpectation expectation, ITypeComputationState state)
protected List<LightweightTypeReference>	computeCollectionTypeCandidates(XCollectionLiteral literal, JvmGenericType collectionType, LightweightTypeReference elementTypeExpectation, ITypeComputationState state) Creates a list of collection type references from the element types of a collection literal.
void	computeType(XListLiteral literal, ITypeComputationState state) Entry point from the XbaseTypeComputer.
protected void	computeType(XListLiteral literal, JvmGenericType listType, ITypeExpectation expectation, ITypeComputationState state)
void	computeType(XSetLiteral literal, ITypeComputationState state) Entry point from the XbaseTypeComputer.
protected void	computeType(XSetLiteral literal, JvmGenericType setType, JvmGenericType mapType, ITypeExpectation expectation, ITypeComputationState state)
protected ITypeComputationResult	computeTypes(XExpression element, LightweightTypeReference expectation, ITypeComputationState state)
protected LightweightTypeReference	createCollectionTypeReference(JvmGenericType collectionType, LightweightTypeReference elementType, LightweightTypeReference expectedType, ITypeReferenceOwner owner) Creates a collection type reference that comes as close as possible / necessary to its expected type.
protected LightweightTypeReference	createMapTypeReference(JvmGenericType mapType, LightweightTypeReference pairType, LightweightTypeReference expectation, ITypeReferenceOwner owner) Creates a map type reference that comes as close as possible / necessary to its expected type.
protected LightweightTypeReference	createNormalizedPairType(LightweightTypeReference pairType, LightweightTypeReference mapType, ITypeReferenceOwner owner) The map type may be constructed from different pairs, e.g. the pair's type arguments don't need to be as strict as the map suggests.
protected LightweightTypeReference	doNormalizeElementType(LightweightTypeReference actual, LightweightTypeReference expected) If the expected type is not a wildcard, it may supersede the actual element type.
protected LightweightTypeReference	getCommonSuperType(List<LightweightTypeReference> types, ITypeComputationState state) Specializes the super implementation such that is allows an empty list of types.
protected LightweightTypeReference	getElementOrComponentType(LightweightTypeReference iterableOrArray, ITypeComputationState state)
protected LightweightTypeReference	getElementOrComponentType(LightweightTypeReference iterableOrArray, ITypeReferenceOwner owner) Delegates to ElementOrComponentTypeComputer.compute(LightweightTypeReference, ITypeReferenceOwner).
protected LightweightTypeReference	getMapExpectation(LightweightTypeReference expectation) If the expected type is a subtype of Map, the resolved super type is returned.
protected void	handleCollectionTypeNotAvailable(XCollectionLiteral literal, ITypeComputationState state, Class<?> clazz) Process all children and assign an unknown type to the literal.
protected boolean	isExpectedType(LightweightTypeReference expectation, Class<?> clazz)
protected boolean	isIterableExpectation(LightweightTypeReference expectation)
protected boolean	isMapExpectation(LightweightTypeReference expectation)
protected boolean	isMapLiteral(LightweightTypeReference expectation, LightweightTypeReference elementType)
protected boolean	isSubtypeButNotSynonym(LightweightTypeReference expectation, Class<?> clazz) Same as LightweightTypeReference.isSubtypeOf(Class) but does not accept synonym types as subtypes.
protected boolean	matchesExpectation(LightweightTypeReference elementType, LightweightTypeReference expectation) Implements fall-back strategy.
protected LightweightTypeReference	normalizeElementType(LightweightTypeReference collectionElementType, LightweightTypeReference expectedCollectionType, ITypeReferenceOwner owner) The expected collection type may drive the type of the elements in the collection if the type is used as an invariant type.
protected LightweightTypeReference	normalizeFunctionTypeReference(LightweightTypeReference type) A function type reference may be known to have the type argument Number but still use a more specific return type Integer.
protected void	refineElementTypeExpectation(XCollectionLiteral literal, LightweightTypeReference expectation, ITypeComputationState state)
protected void	setUnboundCollectionType(XCollectionLiteral literal, JvmGenericType collectionType, ITypeExpectation expectation, LightweightTypeReference elementTypeExpectation, ITypeComputationState state)

Methods inherited from class org.eclipse.xtext.xbase.typesystem.computation.AbstractTypeComputer

deferredBindTypeArgument, findDeclaredType, findDeclaredType, getCommonSuperType, getPrimitiveVoid, getRawTypeForName, getRawTypeForName, getTypeForName

Methods inherited from class java.lang.Object

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

Constructor Detail

CollectionLiteralsTypeComputer

public CollectionLiteralsTypeComputer()

Method Detail

computeType

public void computeType(XSetLiteral literal,
               ITypeComputationState state)

Entry point from the XbaseTypeComputer.

computeType

public void computeType(XListLiteral literal,
               ITypeComputationState state)

Entry point from the XbaseTypeComputer.

getCommonSuperType

protected LightweightTypeReference getCommonSuperType(List<LightweightTypeReference> types,
                                          ITypeComputationState state)

Specializes the super implementation such that is allows an empty list of types. Returns null for those. Computes the common super type for the given list of types. The list may not be empty.

Overrides:

getCommonSuperType in class AbstractTypeComputer

computeType

protected void computeType(XSetLiteral literal,
               JvmGenericType setType,
               JvmGenericType mapType,
               ITypeExpectation expectation,
               ITypeComputationState state)

setUnboundCollectionType

protected void setUnboundCollectionType(XCollectionLiteral literal,
                            JvmGenericType collectionType,
                            ITypeExpectation expectation,
                            LightweightTypeReference elementTypeExpectation,
                            ITypeComputationState state)

refineElementTypeExpectation

protected void refineElementTypeExpectation(XCollectionLiteral literal,
                                LightweightTypeReference expectation,
                                ITypeComputationState state)

isMapLiteral

protected boolean isMapLiteral(LightweightTypeReference expectation,
                   LightweightTypeReference elementType)

isMapExpectation

protected boolean isMapExpectation(LightweightTypeReference expectation)

computeType

protected void computeType(XListLiteral literal,
               JvmGenericType listType,
               ITypeExpectation expectation,
               ITypeComputationState state)

computeArrayLiteralType

protected void computeArrayLiteralType(XListLiteral literal,
                           LightweightTypeReference expectedArrayType,
                           ITypeExpectation expectation,
                           ITypeComputationState state)

computeTypes

protected ITypeComputationResult computeTypes(XExpression element,
                                  LightweightTypeReference expectation,
                                  ITypeComputationState state)

handleCollectionTypeNotAvailable

protected void handleCollectionTypeNotAvailable(XCollectionLiteral literal,
                                    ITypeComputationState state,
                                    Class<?> clazz)

Process all children and assign an unknown type to the literal.

createNormalizedPairType

protected LightweightTypeReference createNormalizedPairType(LightweightTypeReference pairType,
                                                LightweightTypeReference mapType,
                                                ITypeReferenceOwner owner)

The map type may be constructed from different pairs, e.g. the pair's type arguments don't need to be as strict as the map suggests. The pair's expectation is adjusted accordingly.

createCollectionTypeReference

protected LightweightTypeReference createCollectionTypeReference(JvmGenericType collectionType,
                                                     LightweightTypeReference elementType,
                                                     LightweightTypeReference expectedType,
                                                     ITypeReferenceOwner owner)

Creates a collection type reference that comes as close as possible / necessary to its expected type.

createMapTypeReference

protected LightweightTypeReference createMapTypeReference(JvmGenericType mapType,
                                              LightweightTypeReference pairType,
                                              LightweightTypeReference expectation,
                                              ITypeReferenceOwner owner)

Creates a map type reference that comes as close as possible / necessary to its expected type.

matchesExpectation

protected boolean matchesExpectation(LightweightTypeReference elementType,
                         LightweightTypeReference expectation)

Implements fall-back strategy. If the expected type of a collection literal does not match the actual type, but the expected element types would match the actual element type, the collection literal will be successfully typed according to the expectation.

getMapExpectation

protected LightweightTypeReference getMapExpectation(LightweightTypeReference expectation)

If the expected type is a subtype of Map, the resolved super type is returned. This allows to query for the type arguments that are available on the expectation.

normalizeElementType

protected LightweightTypeReference normalizeElementType(LightweightTypeReference collectionElementType,
                                            LightweightTypeReference expectedCollectionType,
                                            ITypeReferenceOwner owner)

The expected collection type may drive the type of the elements in the collection if the type is used as an invariant type. In other word, an expectation of the form Collection<CharSequence> may yield a type List<CharSequence> for the literal ['a'] even though it would be List<? extends String> if no expectation was given.

isIterableExpectation

protected boolean isIterableExpectation(LightweightTypeReference expectation)

isExpectedType

protected boolean isExpectedType(LightweightTypeReference expectation,
                     Class<?> clazz)

isSubtypeButNotSynonym

protected boolean isSubtypeButNotSynonym(LightweightTypeReference expectation,
                             Class<?> clazz)

Same as LightweightTypeReference.isSubtypeOf(Class) but does not accept synonym types as subtypes.

normalizeFunctionTypeReference

protected LightweightTypeReference normalizeFunctionTypeReference(LightweightTypeReference type)

A function type reference may be known to have the type argument Number but still use a more specific return type Integer. Normalization converts such a reference to the return type Number.

doNormalizeElementType

protected LightweightTypeReference doNormalizeElementType(LightweightTypeReference actual,
                                              LightweightTypeReference expected)

If the expected type is not a wildcard, it may supersede the actual element type.

computeCollectionTypeCandidates

protected List<LightweightTypeReference> computeCollectionTypeCandidates(XCollectionLiteral literal,
                                                             JvmGenericType collectionType,
                                                             LightweightTypeReference elementTypeExpectation,
                                                             ITypeComputationState state)

Creates a list of collection type references from the element types of a collection literal.

getElementOrComponentType

protected LightweightTypeReference getElementOrComponentType(LightweightTypeReference iterableOrArray,
                                                 ITypeComputationState state)

getElementOrComponentType

protected LightweightTypeReference getElementOrComponentType(LightweightTypeReference iterableOrArray,
                                                 ITypeReferenceOwner owner)

Delegates to ElementOrComponentTypeComputer.compute(LightweightTypeReference, ITypeReferenceOwner). Clients may override.