参考： https://www.cnblogs.com/LiZhiW/p/4317198.html https://www.jianshu.com/p/6c9b26db6d6d https://segmentfault.com/a/1190000010866959#articleHeader1 https://stackoverrun.com/cn/q/261563 https://yq.aliyun.com/articles/293129/ https://logging.apache.org/log4net/release/sdk/index.html#
