Java 字段不存在多态

 1 public class Main{
 2     public static void main(String[] args) {
 3         A Class = new A();
 4         System.out.println(Class.a);
 5         System.out.println(Class.getA());
 6         A AClass = new B();
 7         System.out.println(AClass.a);
 8         System.out.println(AClass.getA());
 9         B BClass = new B();
10         System.out.println(BClass.a);
11         System.out.println(BClass.getA());
12     }
13 }
14 
15 class A{
16     public int a = 0;
17     public int getA(){
18         return a;
19     }
20 }
21 
22 class B extends A{
23     public int a = 1;
24     public int getA(){
25         return a;
26     }
27 }

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