private static boolean isInExtendsList( final RefJavaElement to, final PsiReferenceList extendsList) { if (extendsList != null) { final PsiJavaCodeReferenceElement[] referenceElements = extendsList.getReferenceElements(); for (PsiJavaCodeReferenceElement referenceElement : referenceElements) { final PsiReferenceParameterList parameterList = referenceElement.getParameterList(); if (parameterList != null) { for (PsiType type : parameterList.getTypeArguments()) { if (extendsList .getManager() .areElementsEquivalent(PsiUtil.resolveClassInType(type), to.getElement())) { return true; } } } } } return false; }
public static String checkMethodReferenceContext( PsiMethodReferenceExpression methodRef, PsiElement resolve, PsiType functionalInterfaceType) { final PsiClass containingClass = resolve instanceof PsiMethod ? ((PsiMethod) resolve).getContainingClass() : (PsiClass) resolve; final boolean isStaticSelector = isStaticallyReferenced(methodRef); final PsiElement qualifier = methodRef.getQualifier(); boolean isMethodStatic = false; boolean receiverReferenced = false; boolean isConstructor = true; if (resolve instanceof PsiMethod) { final PsiMethod method = (PsiMethod) resolve; isMethodStatic = method.hasModifierProperty(PsiModifier.STATIC); isConstructor = method.isConstructor(); receiverReferenced = hasReceiver(methodRef, method, functionalInterfaceType); if (method.hasModifierProperty(PsiModifier.ABSTRACT) && qualifier instanceof PsiSuperExpression) { return "Abstract method '" + method.getName() + "' cannot be accessed directly"; } } if (!receiverReferenced && isStaticSelector && !isMethodStatic && !isConstructor) { return "Non-static method cannot be referenced from a static context"; } if (!receiverReferenced && !isStaticSelector && isMethodStatic) { return "Static method referenced through non-static qualifier"; } if (receiverReferenced && isStaticSelector && isMethodStatic && !isConstructor) { return "Static method referenced through receiver"; } if (isMethodStatic && isStaticSelector && qualifier instanceof PsiTypeElement) { final PsiJavaCodeReferenceElement referenceElement = PsiTreeUtil.getChildOfType(qualifier, PsiJavaCodeReferenceElement.class); if (referenceElement != null) { final PsiReferenceParameterList parameterList = referenceElement.getParameterList(); if (parameterList != null && parameterList.getTypeArguments().length > 0) { return "Parameterized qualifier on static method reference"; } } } if (isConstructor) { if (containingClass != null && PsiUtil.isInnerClass(containingClass) && containingClass.isPhysical()) { PsiClass outerClass = containingClass.getContainingClass(); if (outerClass != null && !InheritanceUtil.hasEnclosingInstanceInScope(outerClass, methodRef, true, false)) { return "An enclosing instance of type " + PsiFormatUtil.formatClass(outerClass, PsiFormatUtilBase.SHOW_NAME) + " is not in scope"; } } } return null; }