有没有办法在Java中重载Integer取消装箱方法？

Question

I am trying to determine if the unboxing method Java uses can be modified. The purpose of this is to be able to do:

class IInteger extends Integer {
  @Override
  public int unboxToPrimitive(){
    return ++val;
  }
}

IInteger i = 10;
System.out.print(i); // 11

That is, overloading the method and having it return ++val instead of val.

Answer 1

No. It isn't possible, first Integer is final and cannot be sub-classed. Second, you can't overload operators in Java. Next, you can't have autoboxing for custom types. Finally, you aren't actually using unboxing in your println (you can call print on a reference type).

However , if I understand what you really want, you could use an AtomicInteger and incrementAndGet() (instead of get() and change your other methods as necessary).

Answer 2

不，你甚至无法扩展java.lang.Integer因为它是一个最终的类。