0.0和-0.0

    public static void main(String[] args) {
        int i = 0;
        Float sphPool = 0.25f;
        Float r = i * sphPool * (-1);
        System.out.println(Float.valueOf(r.toString()));
        System.out.println(String.valueOf(r));
    }

孤陋寡闻,原来还有-0.0,0.0