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; }
// uses hierarchy signature tree if available, traverses class structure by itself otherwise public static boolean processDirectSuperMethodsSmart( @NotNull PsiMethod method, @NotNull Processor<PsiMethod> superMethodProcessor) { // boolean old = PsiSuperMethodUtil.isSuperMethod(method, superMethod); PsiClass aClass = method.getContainingClass(); if (aClass == null) return false; if (!canHaveSuperMethod(method, true, false)) return false; Map<MethodSignature, HierarchicalMethodSignature> cachedMap = SIGNATURES_KEY.getCachedValueOrNull(aClass); if (cachedMap != null) { HierarchicalMethodSignature signature = cachedMap.get(method.getSignature(PsiSubstitutor.EMPTY)); if (signature != null) { List<HierarchicalMethodSignature> superSignatures = signature.getSuperSignatures(); for (HierarchicalMethodSignature superSignature : superSignatures) { if (!superMethodProcessor.process(superSignature.getMethod())) return false; } return true; } } PsiClassType[] directSupers = aClass.getSuperTypes(); for (PsiClassType directSuper : directSupers) { PsiClassType.ClassResolveResult resolveResult = directSuper.resolveGenerics(); if (resolveResult.getSubstitutor() != PsiSubstitutor.EMPTY) { // generics break; } PsiClass directSuperClass = resolveResult.getElement(); if (directSuperClass == null) continue; PsiMethod[] candidates = directSuperClass.findMethodsBySignature(method, false); for (PsiMethod candidate : candidates) { if (PsiUtil.canBeOverriden(candidate)) { if (!superMethodProcessor.process(candidate)) return false; } } return true; } List<HierarchicalMethodSignature> superSignatures = method.getHierarchicalMethodSignature().getSuperSignatures(); for (HierarchicalMethodSignature superSignature : superSignatures) { if (!superMethodProcessor.process(superSignature.getMethod())) return false; } return true; }
public static PsiSubstitutor getSubstitutor( @NotNull PsiMethod method, @NotNull PsiClassType.ClassResolveResult resolveResult) { final PsiClass derivedClass = resolveResult.getElement(); LOG.assertTrue(derivedClass != null); final PsiClass methodContainingClass = method.getContainingClass(); LOG.assertTrue(methodContainingClass != null); PsiSubstitutor initialSubst = resolveResult.getSubstitutor(); final PsiSubstitutor superClassSubstitutor = TypeConversionUtil.getSuperClassSubstitutor( methodContainingClass, derivedClass, PsiSubstitutor.EMPTY); for (PsiTypeParameter param : superClassSubstitutor.getSubstitutionMap().keySet()) { final PsiType substitute = superClassSubstitutor.substitute(param); if (substitute != null) { initialSubst = initialSubst.put(param, initialSubst.substitute(substitute)); } } return initialSubst; }
@Nullable public static PsiMethod getFunctionalInterfaceMethod(PsiClassType.ClassResolveResult result) { final PsiClass psiClass = result.getElement(); if (psiClass != null) { final MethodSignature methodSignature = getFunction(psiClass); if (methodSignature != null) { return getMethod(psiClass, methodSignature); } } return null; }
private static boolean processSuperTypes( @NotNull PsiClass aClass, @NotNull PsiScopeProcessor processor, @Nullable Set<PsiClass> visited, PsiElement last, @NotNull PsiElement place, @NotNull ResolveState state, boolean isRaw, @NotNull PsiElementFactory factory, @NotNull LanguageLevel languageLevel) { boolean resolved = false; for (final PsiClassType superType : aClass.getSuperTypes()) { final PsiClassType.ClassResolveResult superTypeResolveResult = superType.resolveGenerics(); PsiClass superClass = superTypeResolveResult.getElement(); if (superClass == null) continue; PsiSubstitutor finalSubstitutor = obtainFinalSubstitutor( superClass, superTypeResolveResult.getSubstitutor(), aClass, state.get(PsiSubstitutor.KEY), factory, languageLevel); if (aClass instanceof PsiTypeParameter && PsiUtil.isRawSubstitutor(superClass, finalSubstitutor)) { finalSubstitutor = PsiSubstitutor.EMPTY; } if (!processDeclarationsInClass( superClass, processor, state.put(PsiSubstitutor.KEY, finalSubstitutor), visited, last, place, isRaw)) { resolved = true; } } return !resolved; }
private boolean hasTypeParametersToInfer(PsiClassType classType) { final PsiClassType.ClassResolveResult resolveResult = classType.resolveGenerics(); PsiClass aClass = resolveResult.getElement(); if (aClass == null) return false; final Iterable<PsiTypeParameter> iterable = com.intellij.psi.util.PsiUtil.typeParametersIterable(aClass); if (!iterable.iterator().hasNext()) { return false; } for (PsiTypeParameter parameter : iterable) { PsiType type = resolveResult.getSubstitutor().substitute(parameter); if (type != null) { if (!(type instanceof PsiWildcardType) || ((PsiWildcardType) type).getBound() != null) { return false; } } } return true; }
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; }
@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); }
@NotNull private static LookupElement castQualifier( @NotNull LookupElement item, @Nullable final PsiTypeLookupItem castTypeItem, @Nullable PsiType plainQualifier, JavaCompletionProcessor processor) { if (castTypeItem == null) { return item; } if (plainQualifier != null) { Object o = item.getObject(); if (o instanceof PsiMethod) { PsiType castType = castTypeItem.getType(); if (plainQualifier instanceof PsiClassType && castType instanceof PsiClassType) { PsiMethod method = (PsiMethod) o; PsiClassType.ClassResolveResult plainResult = ((PsiClassType) plainQualifier).resolveGenerics(); PsiClass plainClass = plainResult.getElement(); if (plainClass != null && plainClass.findMethodBySignature(method, true) != null) { PsiClass castClass = ((PsiClassType) castType).resolveGenerics().getElement(); if (castClass == null || !castClass.isInheritor(plainClass, true)) { return item; } PsiSubstitutor plainSub = plainResult.getSubstitutor(); PsiSubstitutor castSub = TypeConversionUtil.getSuperClassSubstitutor(plainClass, (PsiClassType) castType); PsiType returnType = method.getReturnType(); if (method.getSignature(plainSub).equals(method.getSignature(castSub))) { PsiType typeAfterCast = toRaw(castSub.substitute(returnType)); PsiType typeDeclared = toRaw(plainSub.substitute(returnType)); if (typeAfterCast != null && typeDeclared != null && typeAfterCast.isAssignableFrom(typeDeclared) && processor.isAccessible(plainClass.findMethodBySignature(method, true))) { return item; } } } } } else if (containsMember(plainQualifier, o)) { return item; } } return LookupElementDecorator.withInsertHandler( item, new InsertHandlerDecorator<LookupElement>() { @Override public void handleInsert( InsertionContext context, LookupElementDecorator<LookupElement> item) { final Document document = context.getEditor().getDocument(); context.commitDocument(); final PsiFile file = context.getFile(); final PsiJavaCodeReferenceElement ref = PsiTreeUtil.findElementOfClassAtOffset( file, context.getStartOffset(), PsiJavaCodeReferenceElement.class, false); if (ref != null) { final PsiElement qualifier = ref.getQualifier(); if (qualifier != null) { final CommonCodeStyleSettings settings = context.getCodeStyleSettings(); final String parenSpace = settings.SPACE_WITHIN_PARENTHESES ? " " : ""; document.insertString(qualifier.getTextRange().getEndOffset(), parenSpace + ")"); final String spaceWithin = settings.SPACE_WITHIN_CAST_PARENTHESES ? " " : ""; final String prefix = "(" + parenSpace + "(" + spaceWithin; final String spaceAfter = settings.SPACE_AFTER_TYPE_CAST ? " " : ""; final int exprStart = qualifier.getTextRange().getStartOffset(); document.insertString(exprStart, prefix + spaceWithin + ")" + spaceAfter); CompletionUtil.emulateInsertion(context, exprStart + prefix.length(), castTypeItem); PsiDocumentManager.getInstance(file.getProject()) .doPostponedOperationsAndUnblockDocument(document); context.getEditor().getCaretModel().moveToOffset(context.getTailOffset()); } } item.getDelegate().handleInsert(context); } }); }
// uses hierarchy signature tree if available, traverses class structure by itself otherwise public static boolean isSuperMethodSmart( @NotNull PsiMethod method, @NotNull PsiMethod superMethod) { // boolean old = PsiSuperMethodUtil.isSuperMethod(method, superMethod); if (method == superMethod) return false; PsiClass aClass = method.getContainingClass(); PsiClass superClass = superMethod.getContainingClass(); if (aClass == null || superClass == null || superClass == aClass) return false; if (!canHaveSuperMethod(method, true, false)) return false; PsiMethod[] superMethods = null; Map<MethodSignature, HierarchicalMethodSignature> cachedMap = SIGNATURES_KEY.getCachedValueOrNull(aClass); if (cachedMap != null) { HierarchicalMethodSignature signature = cachedMap.get(method.getSignature(PsiSubstitutor.EMPTY)); if (signature != null) { superMethods = MethodSignatureUtil.convertMethodSignaturesToMethods(signature.getSuperSignatures()); } } if (superMethods == null) { PsiClassType[] directSupers = aClass.getSuperTypes(); List<PsiMethod> found = null; boolean canceled = false; for (PsiClassType directSuper : directSupers) { PsiClassType.ClassResolveResult resolveResult = directSuper.resolveGenerics(); if (resolveResult.getSubstitutor() != PsiSubstitutor.EMPTY) { // generics canceled = true; break; } PsiClass directSuperClass = resolveResult.getElement(); if (directSuperClass == null) continue; PsiMethod[] candidates = directSuperClass.findMethodsBySignature(method, false); if (candidates.length != 0) { if (found == null) found = new ArrayList<PsiMethod>(); for (PsiMethod candidate : candidates) { if (PsiUtil.canBeOverriden(candidate)) found.add(candidate); } } } superMethods = canceled ? null : found == null ? PsiMethod.EMPTY_ARRAY : found.toArray(new PsiMethod[found.size()]); } if (superMethods == null) { superMethods = MethodSignatureUtil.convertMethodSignaturesToMethods( method.getHierarchicalMethodSignature().getSuperSignatures()); } for (PsiMethod superCandidate : superMethods) { if (superMethod.equals(superCandidate) || isSuperMethodSmart(superCandidate, superMethod)) return true; } return false; }
private static Map<MethodSignature, HierarchicalMethodSignature> buildMethodHierarchy( PsiClass aClass, PsiSubstitutor substitutor, final boolean includePrivates, final Set<PsiClass> visited, boolean isInRawContext) { Map<MethodSignature, HierarchicalMethodSignature> result = new LinkedHashMap<MethodSignature, HierarchicalMethodSignature>(); final Map<MethodSignature, List<PsiMethod>> sameParameterErasureMethods = new THashMap<MethodSignature, List<PsiMethod>>( MethodSignatureUtil.METHOD_PARAMETERS_ERASURE_EQUALITY); Map<MethodSignature, HierarchicalMethodSignatureImpl> map = new THashMap<MethodSignature, HierarchicalMethodSignatureImpl>( new TObjectHashingStrategy<MethodSignature>() { @Override public int computeHashCode(MethodSignature signature) { return MethodSignatureUtil.METHOD_PARAMETERS_ERASURE_EQUALITY.computeHashCode( signature); } @Override public boolean equals(MethodSignature o1, MethodSignature o2) { if (!MethodSignatureUtil.METHOD_PARAMETERS_ERASURE_EQUALITY.equals(o1, o2)) return false; List<PsiMethod> list = sameParameterErasureMethods.get(o1); boolean toCheckReturnType = list != null && list.size() > 1; if (!toCheckReturnType) return true; PsiType returnType1 = ((MethodSignatureBackedByPsiMethod) o1).getMethod().getReturnType(); PsiType returnType2 = ((MethodSignatureBackedByPsiMethod) o2).getMethod().getReturnType(); if (returnType1 == null && returnType2 == null) return true; if (returnType1 == null || returnType2 == null) return false; PsiType erasure1 = TypeConversionUtil.erasure(o1.getSubstitutor().substitute(returnType1)); PsiType erasure2 = TypeConversionUtil.erasure(o2.getSubstitutor().substitute(returnType2)); return erasure1.equals(erasure2); } }); for (PsiMethod method : aClass.getMethods()) { if (!method.isValid()) { throw new PsiInvalidElementAccessException( method, "class.valid=" + aClass.isValid() + "; name=" + method.getName()); } if (!includePrivates && method.hasModifierProperty(PsiModifier.PRIVATE)) continue; final MethodSignatureBackedByPsiMethod signature = MethodSignatureBackedByPsiMethod.create(method, substitutor, isInRawContext); HierarchicalMethodSignatureImpl newH = new HierarchicalMethodSignatureImpl(signature); List<PsiMethod> list = sameParameterErasureMethods.get(signature); if (list == null) { list = new SmartList<PsiMethod>(); sameParameterErasureMethods.put(signature, list); } list.add(method); LOG.assertTrue(newH.getMethod().isValid()); result.put(signature, newH); map.put(signature, newH); } for (PsiClassType superType : aClass.getSuperTypes()) { PsiClassType.ClassResolveResult superTypeResolveResult = superType.resolveGenerics(); PsiClass superClass = superTypeResolveResult.getElement(); if (superClass == null) continue; if (!visited.add(superClass)) continue; // cyclic inheritance final PsiSubstitutor superSubstitutor = superTypeResolveResult.getSubstitutor(); PsiSubstitutor finalSubstitutor = obtainFinalSubstitutor(superClass, superSubstitutor, substitutor, isInRawContext); final boolean isInRawContextSuper = (isInRawContext || PsiUtil.isRawSubstitutor(superClass, superSubstitutor)) && superClass.getTypeParameters().length != 0; Map<MethodSignature, HierarchicalMethodSignature> superResult = buildMethodHierarchy(superClass, finalSubstitutor, false, visited, isInRawContextSuper); visited.remove(superClass); List<Pair<MethodSignature, HierarchicalMethodSignature>> flattened = new ArrayList<Pair<MethodSignature, HierarchicalMethodSignature>>(); for (Map.Entry<MethodSignature, HierarchicalMethodSignature> entry : superResult.entrySet()) { HierarchicalMethodSignature hms = entry.getValue(); MethodSignature signature = entry.getKey(); PsiClass containingClass = hms.getMethod().getContainingClass(); List<HierarchicalMethodSignature> supers = new ArrayList<HierarchicalMethodSignature>(hms.getSuperSignatures()); for (HierarchicalMethodSignature aSuper : supers) { PsiClass superContainingClass = aSuper.getMethod().getContainingClass(); if (containingClass != null && superContainingClass != null && !containingClass.isInheritor(superContainingClass, true)) { // methods must be inherited from unrelated classes, so flatten hierarchy here // class C implements SAM1, SAM2 { void methodimpl() {} } // hms.getSuperSignatures().remove(aSuper); flattened.add( new Pair<MethodSignature, HierarchicalMethodSignature>(signature, aSuper)); } } putInMap(aClass, result, map, hms, signature); } for (Pair<MethodSignature, HierarchicalMethodSignature> pair : flattened) { putInMap(aClass, result, map, pair.second, pair.first); } } for (Map.Entry<MethodSignature, HierarchicalMethodSignatureImpl> entry : map.entrySet()) { HierarchicalMethodSignatureImpl hierarchicalMethodSignature = entry.getValue(); MethodSignature methodSignature = entry.getKey(); if (result.get(methodSignature) == null && PsiUtil.isAccessible( aClass.getProject(), hierarchicalMethodSignature.getMethod(), aClass, aClass)) { LOG.assertTrue(hierarchicalMethodSignature.getMethod().isValid()); result.put(methodSignature, hierarchicalMethodSignature); } } return result; }
@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; }