需要引入的依赖
spring,mybatis,mybatis-spring(整合的jar包)，mysql相关的jar包，druid(它要创建sqlsessionfactory,所以要用到数据源对象)，lombook,log4j(为了展示日志)
事务的理解:https://blog.csdn.net/jiangyu1013/article/details/84397366?utm_medium=distribute.pc_relevant.none-task-blog-BlogCommendFromMachineLearnPai2-2.edu_weight&depth_1-utm_source=distribute.pc_relevant.none-task-blog-BlogCommendFromMachineLearnPai2-2.edu_weight
