boolean (@Nullable PsiType type) { PsiClassType classType = tryCast(type, PsiClassType.class); if (classType == null) return false; if (classType.getParameterCount() != 1) return false; PsiType typeParameter = classType.getParameters()[0]; PsiClass parameterClass = PsiUtil.resolveClassInClassTypeOnly(typeParameter); if (parameterClass == null) return false; return JAVA_UTIL_OPTIONAL.equals(parameterClass.getQualifiedName()); }