java:override

(1)override:
class Parent{
    Object func(Number n){
    ...
    }
}
class Child extends Parent{
    Object func(Number n){
    ...
    }
}

This is so-called override.

override的含义，就是俗称的“多态”

Child.func和Parent.func可以看作是占用了虚函数指针表里面的同一个Entry.即：Child.func覆盖了Parent.func.