If a child class declares a member variable with the same name as a member variable of the parent class, the member variable of the parent class is called hidden (hiding).
If a child class declares a member method with the same name as a parent class member method, the member method of the parent class is called overridden (overriding).
The keyword this and super are respectively used to indicate a member variable or member method of the same name in the subclass and parent class.
You can use the keyword this and super to specify the variable you want to use when the member variables of the parent class, the member variables of the subclass, and the local variables used by the class method have the same name, or if they have the same name.
class a{ int x; A member variable is declared in Class A x}class b extends a{ //class B inherits Class A and also inherits the member variable x of Class A. int x; // In class B, you declare a member variable x void m () { The int x; //method M also declares its own local variable x super.x=2; // super modifies the x of its class parent Class A. this.x=1; // this modifies the x of the Class B in which it is located x=100; // Here x is the local variable x of the method M itself;}}
Super Keyword Reference blog http://www.cnblogs.com/xdp-gacl/p/3635948.html
Super and this