给定一个double类型的浮点数base和int类型的整数exponent。求base的exponent次方

package Solution;

class Solution {
    public static void main(String[] args) {
        System.out.println(Power(2.5, 5));

    }

    public static double Power(double base, int exponent) {

        double sum = 0, temp = base;
        if (exponent == 0) {
            return 1;
        }
        if (exponent == 1) {
            return base;
        }
        if (exponent > 1) {
            for (int i = 1; i < exponent; i++) {
                sum = temp * base;
                temp = sum;
            }
        } else {
            for (int i = -1; i > exponent; i--) {
                sum = temp * base;
                temp = sum;
            }
            sum = 1 / sum;

        }

        return sum;

    }
}