changes to level!

1 field is changed---fanuction's parameter

2 behavior is changed---lambda for java8

3 block of codes is changed---class abstact interface

4 object is changed---design code or named frame

 

it is so important that..........

 

changes is our think<-->final is the frame about class abstract interface

so,

1 what is a funtion

　   changes to a field

2 what is a lambda

     changes to a function

3 what is a class

　　changes to a bolck codes

4 what is a design code or frame

　　changes to a object