boolean (@NotNull PsiElement element) { PsiCaseLabelElementList list = ObjectUtils.tryCast(element.getParent(), PsiCaseLabelElementList.class); if (list == null || list.getElementCount() != 2) return false; PsiCaseLabelElement[] elements = list.getElements(); return elements[0] instanceof PsiExpression expr && ExpressionUtils.isNullLiteral(expr) && elements[1] instanceof PsiDefaultCaseLabelElement; }