The difference between public private protected default in Java

1, public:public indicates that the data member, the member function is open to all users, all users can directly make the call

2, private:private means private, private means that except class himself, no one can directly use, private property sacred inviolability, even children, friends, can not be used.

3, protected:protected for children, friends, is public, free to use, without any restrictions, and for other external class,protected become private.

Scope Current class same package descendant class other package

Public√√√√

Protected√√√x

Private√xxx

Instance:
Demo.java

Package Study;public class Method {private int privatea;public  int publica;protected int Protecteda;int a;// Initial private void Privatedemo () {}public void Publicdemo () {}protected void Protecteddemo () {}void demo () {}}

Idemo.java Testing Subclass access Rights

Package Study;public class Idemo extends Method{public void Mydemo () {//TODO auto-generated method Stubsuper.privatedemo ( );//Cannot access the method of the parent class, since it is defined that privatesuper.privatea;//cannot access the domain of the parent class, since the definition is Privateint a=super.protecteda;// Public can access Super.publicdemo ();//public can access int in subclass a1=super.protecteda;//protected  You can access the Super.protecteddemo () in the subclass, and//protected  can access the int a2=super in the child class. a;//can access Super.demo () by default in his subclass;//can be accessed by default in his child class}}

The difference between public private protected default in Java