39 New: Hutool

Need to mention that in the guide. Also, if there's a new way to handle system properties or environment variables, that could be part of the new features.

Wait, the user mentioned "Hutool 39 new." Maybe there's a typo here. Typically, versions are like 3.9.0 or similar. So I'll proceed under the assumption that it's version 3.9.0. hutool 39 new

import cn.hutool.core.bean.BeanUtil;