5例子3.txt

Java大学实用教程 耿祥义编著 课件 PPT

class A
{
     protected  double y=12.56;
}
class B extends A
{
     int y=0;
     void g()
     {
         y=y+100;
         System.out.printf("y=%d\n",y);
     }
}
class Example
{    
     public static void main(String args[ ])
     {
         B  b=new B();
            b.y=-100;
            b.g();
     }  
   
}