1. About Private Member variables
Child classes have these member variables in the parent class, regardless of whether the member variables in the parent class are private, common, or other types. However, private member variables in the parent class cannot be accessed directly in the subclass, and must be accessed through the protected, public methods (such as Getter, setter methods) that are inherited from the parent class.
2. About static member variables
Child classes have these member variables in the parent class, regardless of whether the member variables in the parent class are static or non-static.
3, about the quilt class overrides the member variable
Subclasses will have these member variables in the parent class, regardless of whether the member variables in the parent class are overridden by the quilt class.
Subclass can inherit member variables of parent class