一般什么情况下使用Object作为形参接收其他类呢？解决办法

public class Main {// 给你个例子，仔细看看吧    public static Object sum(Object obj1, Object obj2) {        int inttmp1 = 0, inttmp2 = 0;        double doubletmp1 = 0.0, doubletmp2 = 0.0;        if (obj1 instanceof Integer)            inttmp1 = (Integer) obj1;        else if (obj1 instanceof Double)            doubletmp1 = (Double) obj1;        if (obj2 instanceof Integer)            inttmp2 = (Integer) obj2;        else if (obj2 instanceof Double)            doubletmp2 = (Double) obj2;        return doubletmp1 + doubletmp2 + inttmp1 + inttmp2;    }    public static void main(String[] args) {        System.out.println(sum(1, 2));        System.out.println(sum(1.0, 2.5));        System.out.println(sum(1, 2.5));    }}