log4j2 中logger,appender关系
log4j2中Appender/Logger/Root 关系
https://blog.csdn.net/HongZeng_CSDN/article/details/130094219
《Log4j 2 官网文档》多余性（Additivity）
http://ifeve.com/log4j-2-additivity/
log4j2中Appender/Logger/Root 关系
https://blog.csdn.net/HongZeng_CSDN/article/details/130094219
《Log4j 2 官网文档》多余性（Additivity）
http://ifeve.com/log4j-2-additivity/