环境相关概念

环境bean、系统环境bean、系统属性bean

https://blog.csdn.net/topdeveloperr/article/details/88063828?spm=1001.2101.3001.6650.2&utm_medium=distribute.pc_relevant.none-task-blog-2%7Edefault%7ECTRLIST%7ERate-2.pc_relevant_paycolumn_v3&depth_1-utm_source=distribute.pc_relevant.none-task-blog-2%7Edefault%7ECTRLIST%7ERate-2.pc_relevant_paycolumn_v3&utm_relevant_index=5