public static boolean isReceiverType(
PsiType functionalInterfaceType,
PsiClass containingClass,
@Nullable PsiMethod referencedMethod) {
final PsiClassType.ClassResolveResult resolveResult =
PsiUtil.resolveGenericsClassInType(functionalInterfaceType);
final MethodSignature function = LambdaUtil.getFunction(resolveResult.getElement());
if (function != null) {
final int interfaceMethodParamsLength = function.getParameterTypes().length;
if (interfaceMethodParamsLength > 0) {
final PsiType firstParamType =
resolveResult.getSubstitutor().substitute(function.getParameterTypes()[0]);
boolean isReceiver =
isReceiverType(
firstParamType,
containingClass,
PsiUtil.resolveGenericsClassInType(firstParamType).getSubstitutor());
if (isReceiver) {
if (referencedMethod == null) {
if (interfaceMethodParamsLength == 1) return true;
return false;
}
if (referencedMethod.getParameterList().getParametersCount()
!= interfaceMethodParamsLength - 1) {
return false;
}
return true;
}
}
}
return false;
}
@Nullable
public static PsiType getFunctionalInterfaceReturnType(
@Nullable PsiType functionalInterfaceType) {
final PsiClassType.ClassResolveResult resolveResult =
PsiUtil.resolveGenericsClassInType(functionalInterfaceType);
final PsiClass psiClass = resolveResult.getElement();
if (psiClass != null) {
final MethodSignature methodSignature = getFunction(psiClass);
if (methodSignature != null) {
final PsiType returnType = getReturnType(psiClass, methodSignature);
return resolveResult.getSubstitutor().substitute(returnType);
}
}
return null;
}
@NotNull
public static QualifierResolveResult getQualifierResolveResult(
@NotNull PsiMethodReferenceExpression methodReferenceExpression) {
PsiClass containingClass = null;
PsiSubstitutor substitutor = PsiSubstitutor.EMPTY;
final PsiExpression expression = methodReferenceExpression.getQualifierExpression();
if (expression != null) {
final PsiType expressionType = getExpandedType(expression.getType(), expression);
PsiClassType.ClassResolveResult result = PsiUtil.resolveGenericsClassInType(expressionType);
containingClass = result.getElement();
if (containingClass != null) {
substitutor = result.getSubstitutor();
}
if (containingClass == null && expression instanceof PsiReferenceExpression) {
final JavaResolveResult resolveResult =
((PsiReferenceExpression) expression).advancedResolve(false);
final PsiElement resolve = resolveResult.getElement();
if (resolve instanceof PsiClass) {
containingClass = (PsiClass) resolve;
substitutor = resolveResult.getSubstitutor();
return new QualifierResolveResult(containingClass, substitutor, true);
}
}
} else {
final PsiTypeElement typeElement = methodReferenceExpression.getQualifierType();
if (typeElement != null) {
PsiType type = getExpandedType(typeElement.getType(), typeElement);
PsiClassType.ClassResolveResult result = PsiUtil.resolveGenericsClassInType(type);
containingClass = result.getElement();
if (containingClass != null) {
return new QualifierResolveResult(containingClass, result.getSubstitutor(), true);
}
}
}
return new QualifierResolveResult(containingClass, substitutor, false);
}
private static PsiType getLambdaParameterFromType(
int parameterIndex, PsiLambdaExpression lambdaExpression, PsiType conjunct) {
final PsiClassType.ClassResolveResult resolveResult =
PsiUtil.resolveGenericsClassInType(conjunct);
if (resolveResult != null) {
final PsiMethod method = getFunctionalInterfaceMethod(conjunct);
if (method != null) {
final PsiParameter[] parameters = method.getParameterList().getParameters();
if (parameterIndex < parameters.length) {
final PsiType psiType =
getSubstitutor(method, resolveResult)
.substitute(parameters[parameterIndex].getType());
if (!dependsOnTypeParams(psiType, conjunct, lambdaExpression)) {
return GenericsUtil.eliminateWildcards(psiType);
}
}
}
}
return null;
}
public static boolean isReceiverType(
PsiType receiverType, @Nullable PsiClass containingClass, PsiSubstitutor psiSubstitutor) {
if (containingClass != null) {
receiverType = getExpandedType(receiverType, containingClass);
}
final PsiClassType.ClassResolveResult resolveResult =
PsiUtil.resolveGenericsClassInType(receiverType);
final PsiClass receiverClass = resolveResult.getElement();
if (receiverClass != null && isReceiverType(receiverClass, containingClass)) {
if (emptyOrRaw(containingClass, psiSubstitutor)) {
return true;
}
final PsiSubstitutor derivedSubstitutor =
TypeConversionUtil.getClassSubstitutor(containingClass, receiverClass, psiSubstitutor);
return derivedSubstitutor != null
&& TypeConversionUtil.isAssignable(
JavaPsiFacade.getElementFactory(containingClass.getProject())
.createType(containingClass, derivedSubstitutor),
receiverType);
}
return false;
}
private static boolean hasReceiver(
@NotNull PsiMethodReferenceExpression methodRef,
@NotNull PsiMethod method,
PsiType functionalInterfaceType) {
final PsiClassType.ClassResolveResult resolveResult =
PsiUtil.resolveGenericsClassInType(functionalInterfaceType);
final PsiMethod interfaceMethod = LambdaUtil.getFunctionalInterfaceMethod(resolveResult);
final MethodSignature signature =
interfaceMethod != null
? interfaceMethod.getSignature(
LambdaUtil.getSubstitutor(interfaceMethod, resolveResult))
: null;
if (signature == null) {
return false;
}
final PsiType[] parameterTypes = signature.getParameterTypes();
final QualifierResolveResult qualifierResolveResult = getQualifierResolveResult(methodRef);
return (method.getParameterList().getParametersCount() + 1 == parameterTypes.length
|| method.isVarArgs()
&& parameterTypes.length > 0
&& !method.hasModifierProperty(PsiModifier.STATIC))
&& hasReceiver(parameterTypes, qualifierResolveResult, methodRef);
}
private static boolean provablyDistinct(PsiType type1, PsiType type2, int level) {
if (type1 instanceof PsiClassType
&& ((PsiClassType) type1).resolve() instanceof PsiTypeParameter) return false;
if (type2 instanceof PsiClassType
&& ((PsiClassType) type2).resolve() instanceof PsiTypeParameter) return false;
if (type1 instanceof PsiWildcardType) {
if (type2 instanceof PsiWildcardType) {
return provablyDistinct((PsiWildcardType) type1, (PsiWildcardType) type2);
}
if (type2 instanceof PsiCapturedWildcardType) {
return ((PsiWildcardType) type1).isExtends() && level > 0
|| provablyDistinct(
(PsiWildcardType) type1, ((PsiCapturedWildcardType) type2).getWildcard());
}
if (type2 instanceof PsiClassType) {
final PsiClass psiClass2 = PsiUtil.resolveClassInType(type2);
if (psiClass2 == null) return false;
if (((PsiWildcardType) type1).isExtends()) {
final PsiType extendsBound = ((PsiWildcardType) type1).getExtendsBound();
if (extendsBound instanceof PsiArrayType
&& proveArrayTypeDistinct(
((PsiWildcardType) type1).getManager().getProject(),
(PsiArrayType) extendsBound,
type2)) return true;
final PsiClass boundClass1 = PsiUtil.resolveClassInType(extendsBound);
if (boundClass1 == null) return false;
return proveExtendsBoundsDistinct(type1, type2, boundClass1, psiClass2);
}
if (((PsiWildcardType) type1).isSuper()) {
final PsiType superBound = ((PsiWildcardType) type1).getSuperBound();
if (superBound instanceof PsiArrayType
&& proveArrayTypeDistinct(
((PsiWildcardType) type1).getManager().getProject(),
(PsiArrayType) superBound,
type2)) return true;
final PsiClass boundClass1 = PsiUtil.resolveClassInType(superBound);
if (boundClass1 == null || boundClass1 instanceof PsiTypeParameter) return false;
return !InheritanceUtil.isInheritorOrSelf(boundClass1, psiClass2, true);
}
final PsiType bound = ((PsiWildcardType) type1).getBound();
return bound != null && !bound.equals(psiClass2);
}
if (type2 instanceof PsiArrayType) {
return proveArrayTypeDistinct(
((PsiWildcardType) type1).getManager().getProject(), (PsiArrayType) type2, type1);
}
}
if (type1 instanceof PsiCapturedWildcardType)
return provablyDistinct(((PsiCapturedWildcardType) type1).getWildcard(), type2, level);
if (type2 instanceof PsiWildcardType || type2 instanceof PsiCapturedWildcardType)
return provablyDistinct(type2, type1, level);
final PsiClassType.ClassResolveResult classResolveResult1 =
PsiUtil.resolveGenericsClassInType(type1);
final PsiClassType.ClassResolveResult classResolveResult2 =
PsiUtil.resolveGenericsClassInType(type2);
if (Comparing.equal(TypeConversionUtil.erasure(type1), TypeConversionUtil.erasure(type2))) {
final PsiSubstitutor substitutor1 = classResolveResult1.getSubstitutor();
final PsiSubstitutor substitutor2 = classResolveResult2.getSubstitutor();
for (PsiTypeParameter parameter : substitutor1.getSubstitutionMap().keySet()) {
final PsiType substitutedType1 = substitutor1.substitute(parameter);
final PsiType substitutedType2 = substitutor2.substitute(parameter);
if (substitutedType1 == null && substitutedType2 == null) return false;
if (substitutedType1 == null || substitutedType2 == null) {
return true;
} else {
if (provablyDistinct(substitutedType1, substitutedType2, level + 1)) return true;
if (substitutedType1 instanceof PsiWildcardType
&& !((PsiWildcardType) substitutedType1).isBounded()) return true;
}
}
return false;
}
final PsiClass boundClass1 = classResolveResult1.getElement();
final PsiClass boundClass2 = classResolveResult2.getElement();
return type2 != null
&& type1 != null
&& !type1.equals(type2)
&& (!InheritanceUtil.isInheritorOrSelf(boundClass1, boundClass2, true)
|| !InheritanceUtil.isInheritorOrSelf(boundClass2, boundClass1, true));
}
public TypeParamsChecker(PsiElement expression) {
this(
expression,
PsiUtil.resolveGenericsClassInType(getFunctionalInterfaceType(expression, false))
.getElement());
}
@Nullable
public static PsiMethod getFunctionalInterfaceMethod(@Nullable PsiType functionalInterfaceType) {
return getFunctionalInterfaceMethod(
PsiUtil.resolveGenericsClassInType(functionalInterfaceType));
}
@Nullable
public static PsiType getFunctionalInterfaceType(
PsiElement expression, final boolean tryToSubstitute, int paramIdx) {
PsiElement parent = expression.getParent();
PsiElement element = expression;
while (parent instanceof PsiParenthesizedExpression
|| parent instanceof PsiConditionalExpression) {
if (parent instanceof PsiConditionalExpression
&& ((PsiConditionalExpression) parent).getThenExpression() != element
&& ((PsiConditionalExpression) parent).getElseExpression() != element) break;
element = parent;
parent = parent.getParent();
}
if (parent instanceof PsiArrayInitializerExpression) {
final PsiType psiType = ((PsiArrayInitializerExpression) parent).getType();
if (psiType instanceof PsiArrayType) {
return ((PsiArrayType) psiType).getComponentType();
}
} else if (parent instanceof PsiTypeCastExpression) {
final PsiType castType = ((PsiTypeCastExpression) parent).getType();
if (castType instanceof PsiIntersectionType) {
for (PsiType conjunctType : ((PsiIntersectionType) castType).getConjuncts()) {
if (getFunctionalInterfaceMethod(conjunctType) != null) return conjunctType;
}
}
return castType;
} else if (parent instanceof PsiVariable) {
return ((PsiVariable) parent).getType();
} else if (parent instanceof PsiAssignmentExpression
&& expression instanceof PsiExpression
&& !PsiUtil.isOnAssignmentLeftHand((PsiExpression) expression)) {
final PsiExpression lExpression = ((PsiAssignmentExpression) parent).getLExpression();
return lExpression.getType();
} else if (parent instanceof PsiExpressionList) {
final PsiExpressionList expressionList = (PsiExpressionList) parent;
final int lambdaIdx = getLambdaIdx(expressionList, expression);
if (lambdaIdx > -1) {
PsiType cachedType = null;
final Pair<PsiMethod, PsiSubstitutor> method = MethodCandidateInfo.getCurrentMethod(parent);
if (method != null) {
final PsiParameter[] parameters = method.first.getParameterList().getParameters();
cachedType =
lambdaIdx < parameters.length
? method.second.substitute(
getNormalizedType(
parameters[adjustLambdaIdx(lambdaIdx, method.first, parameters)]))
: null;
if (!tryToSubstitute) return cachedType;
}
PsiElement gParent = expressionList.getParent();
if (gParent instanceof PsiAnonymousClass) {
gParent = gParent.getParent();
}
if (gParent instanceof PsiCall) {
final PsiCall contextCall = (PsiCall) gParent;
final JavaResolveResult resolveResult = contextCall.resolveMethodGenerics();
final PsiElement resolve = resolveResult.getElement();
if (resolve instanceof PsiMethod) {
final PsiParameter[] parameters =
((PsiMethod) resolve).getParameterList().getParameters();
final int finalLambdaIdx = adjustLambdaIdx(lambdaIdx, (PsiMethod) resolve, parameters);
if (finalLambdaIdx < parameters.length) {
if (!tryToSubstitute) return getNormalizedType(parameters[finalLambdaIdx]);
if (cachedType != null && paramIdx > -1) {
final PsiMethod interfaceMethod = getFunctionalInterfaceMethod(cachedType);
if (interfaceMethod != null) {
final PsiClassType.ClassResolveResult cachedResult =
PsiUtil.resolveGenericsClassInType(cachedType);
final PsiType interfaceMethodParameterType =
interfaceMethod.getParameterList().getParameters()[paramIdx].getType();
if (!dependsOnTypeParams(
cachedResult.getSubstitutor().substitute(interfaceMethodParameterType),
cachedType,
expression)) {
return cachedType;
}
}
}
return PsiResolveHelper.ourGuard.doPreventingRecursion(
expression,
true,
new Computable<PsiType>() {
@Override
public PsiType compute() {
return resolveResult
.getSubstitutor()
.substitute(getNormalizedType(parameters[finalLambdaIdx]));
}
});
}
}
return null;
}
}
} else if (parent instanceof PsiReturnStatement) {
final PsiLambdaExpression gParent =
PsiTreeUtil.getParentOfType(parent, PsiLambdaExpression.class);
if (gParent != null) {
return getFunctionalInterfaceTypeByContainingLambda(gParent);
} else {
final PsiMethod method = PsiTreeUtil.getParentOfType(parent, PsiMethod.class);
if (method != null) {
return method.getReturnType();
}
}
} else if (parent instanceof PsiLambdaExpression) {
return getFunctionalInterfaceTypeByContainingLambda((PsiLambdaExpression) parent);
}
return null;
}
public static boolean isAcceptable(
PsiLambdaExpression lambdaExpression, final PsiType leftType, boolean checkReturnType) {
if (leftType instanceof PsiIntersectionType) {
for (PsiType conjunctType : ((PsiIntersectionType) leftType).getConjuncts()) {
if (isAcceptable(lambdaExpression, conjunctType, checkReturnType)) return true;
}
return false;
}
final PsiClassType.ClassResolveResult resolveResult =
PsiUtil.resolveGenericsClassInType(GenericsUtil.eliminateWildcards(leftType));
final PsiClass psiClass = resolveResult.getElement();
if (psiClass instanceof PsiAnonymousClass) {
return isAcceptable(
lambdaExpression, ((PsiAnonymousClass) psiClass).getBaseClassType(), checkReturnType);
}
final MethodSignature methodSignature = getFunction(psiClass);
if (methodSignature == null) return false;
final PsiParameter[] lambdaParameters = lambdaExpression.getParameterList().getParameters();
final PsiType[] parameterTypes = methodSignature.getParameterTypes();
if (lambdaParameters.length != parameterTypes.length) return false;
for (int lambdaParamIdx = 0, length = lambdaParameters.length;
lambdaParamIdx < length;
lambdaParamIdx++) {
PsiParameter parameter = lambdaParameters[lambdaParamIdx];
final PsiTypeElement typeElement = parameter.getTypeElement();
if (typeElement != null) {
final PsiType lambdaFormalType = typeElement.getType();
final PsiType methodParameterType = parameterTypes[lambdaParamIdx];
if (lambdaFormalType instanceof PsiPrimitiveType) {
if (methodParameterType instanceof PsiPrimitiveType)
return methodParameterType.equals(lambdaFormalType);
return false;
}
if (!TypeConversionUtil.erasure(lambdaFormalType)
.isAssignableFrom(
TypeConversionUtil.erasure(
GenericsUtil.eliminateWildcards(
resolveResult
.getSubstitutor()
.substitute(
methodSignature
.getSubstitutor()
.substitute(methodParameterType)))))) {
return false;
}
}
}
if (checkReturnType) {
final String uniqueVarName =
JavaCodeStyleManager.getInstance(lambdaExpression.getProject())
.suggestUniqueVariableName("l", lambdaExpression, true);
String canonicalText = leftType.getCanonicalText();
if (leftType instanceof PsiEllipsisType) {
canonicalText = ((PsiEllipsisType) leftType).toArrayType().getCanonicalText();
}
final PsiStatement assignmentFromText =
JavaPsiFacade.getElementFactory(lambdaExpression.getProject())
.createStatementFromText(
canonicalText + " " + uniqueVarName + " = " + lambdaExpression.getText(),
lambdaExpression);
final PsiLocalVariable localVariable =
(PsiLocalVariable)
((PsiDeclarationStatement) assignmentFromText).getDeclaredElements()[0];
LOG.assertTrue(psiClass != null);
PsiType methodReturnType = getReturnType(psiClass, methodSignature);
if (methodReturnType != null) {
methodReturnType =
resolveResult
.getSubstitutor()
.substitute(methodSignature.getSubstitutor().substitute(methodReturnType));
return LambdaHighlightingUtil.checkReturnTypeCompatible(
(PsiLambdaExpression) localVariable.getInitializer(), methodReturnType)
== null;
}
}
return true;
}