工具库主代码参考地址: https://zxfjd3g.github.io/atguigu_utils-docs/chapter2/08_%E6%89%8B%E5%86%99%E6%B6%88%E6%81%AF%E8%AE%A2%E9%98%85%E4%B8%8E%E5%8F%91%E5%B8%83.html#_9-2-%E7%BC%96%E7%A0%81%E5%AE%9E%E7%8E%B0