Class and object summary

Class and object summary

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1. Classes and objects 
     Class is a template ： abstract . Object is a concrete instance 
2. Method 
     Definition 、 call 
3. Object application 
     Reference type ： Basic types （8） int boolean short long float double char byte
4. attribute ： Member variables 
     Default initialization ：
         Numbers ：0    0.0
        char: u0000
        boolean: false
         quote ： null
     Modifier   Attribute types   Property name = Property value 

5. Object creation and use 
    - You have to use new Keywords create objects , Constructors  Person person = new Person()
    - Object properties ： dog.name
    - Object method ： dog.shout()
6. class :
     Static properties ：  attribute 
     Dynamic behavior ：  Method