java - Var-args 重载

Question

谁能解释一下为什么这段代码会抛出一个不明确的重载错误，Integer 方法肯定更具体和适用吗？

谢谢

内德

package object_orientation;
public class Ambiguous {
    //ambiguous error compiler unsure whether boxing is needed or not
    static void overload(Integer... d){
        System.out.println("Integer");
    }

    static void overload(long... d){
        System.out.println("Long");
    }

    public static void main(String a[]){
        int i = 1;
        overload(i);
    }
}

Answer 1

Java 中的这些概念应该有所帮助， 允许装箱+加宽，但不允许加宽+装箱。

这些加宽、拳击和 Vararg 规则应该有所帮助:

1. Primitive Widening > Boxing > Varargs.
2. Widening and Boxing (WB) not allowed.
3. Boxing and Widening (BW) allowed.
4. While overloading, Widening + vararg and Boxing + vararg can only be used in a mutually exclusive manner
5. Widening between wrapper classes not allowed.
6. Widening+varArgs & Boxing+varargs are individually allowed (but not allowed in overloaded version of method).
7. Boxing+Widening is preferred over Boxing+Varargs.

希望这有帮助。