Modifier

To class contains:

　　private: Just for the class of which defined it. 

　　default: For the class of which defined it and the class that in the same package.

　　protected: For the class of which definded it and the class that in the same package and the class inherited from it.

　　public: Anywhere can get it and use it.

Tip:

　　When A class extend B class and B contain private members, A has the private members that inherited from B, but cannot use them.

To class:

　　Only public and default can use.

　　public: anywhere

　　default: must in the same package