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1.基本命令
2.多模块
2.1 如何创建多模块
https://blog.csdn.net/sinat_34344123/article/details/79080601
2.2 模块之间互相调用
https://blog.csdn.net/qq_21383435/article/details/82708772
3.maven引用问题
3.1 无法引入问题
3.1.1 mvn无法引入包
https://blog.csdn.net/qq_21383435/article/details/82715252
3.2 冲突
3.2.1 log4j循环引用冲突
Detected both log4j-over-slf4j.jar AND bound slf4j-log4j12.jar on the class
https://blog.csdn.net/qq_21383435/article/details/82720995