with maven environment, spring boot + mysql + mybatis localhost:8080 https://blog.csdn.net/alantuling_jt/article/details/54893383 model: User class(entity) mapper: UserMapper interface(Dao) service: UserService (process data, use UserMapper methods) (service) controller: UserController class (use UserService methods) (controller) DemoApplication: startup class application.properties: connect mysql pom.xml: config dependencies, plugins, etc.