@Override
    public int hashCode() {
        int h = 0;
        if (null != this.data) {
            for (int i = 0; i < this.data.length; i++) {
                h = 31 * h + data[i++];
            }
        }
        return h;
    }
@param data
           the data to set
metamorphosis-commons/src/main/java/com/taobao/common/store/util/BytesKey.java