1.问题：[org.mybatis.spring.SqlSessionUtils] - Creating a new SqlSession
[org.mybatis.spring.SqlSessionUtils] - SqlSession[org.apache.ibatis.session.defaults.DefaultSqlSession@1a714e6e] was not registered for synchronization because synchronization is not active
[org.springframework.jdbc.datasource.DataSourceUtils] - Fetching JDBC Connection from DataSource
[org.mybatis.spring.transaction.SpringManagedTransaction] - JDBC Connection [jdbc: mysql://localhost:3306/iot, UserName=root@localhost, MySQL Connector Java]* will not be managed by Spring*
[com.haoyifen.mySSMTemplate.dao.UserMapper.selectByPrimaryKey] - ==> Preparing: select ID, USER_ID, USER_NAME, SEX, ADDRESS, PHONE_NUMBER, MAIL_BOX from user where ID = ?
[com.haoyifen.mySSMTemplate.dao.UserMapper.selectByPrimaryKey] - ==> Parameters: 1(Integer)
[com.haoyifen.mySSMTemplate.dao.UserMapper.selectByPrimaryKey] - <== Total: 1
[org.mybatis.spring.SqlSessionUtils] - Closing non transactional SqlSession[org.apache.ibatis.session.defaults.DefaultSqlSession@1a714e6e]
原因:重复扫描事务配置所致，spring-mybatis中扫描了一遍service
<context:component-scan base-package="cn.yzh" >
<context:exclude-filter type="annotation" expression="org.springframework.stereotype.Controller" />
</context:component-scan>
spring-mvc中又扫描了一遍
<context:component-scan base-package="cn.yzh" >
spring如果要使事务生效，就需要cglib为userService生成代理子类，在spring.xml中已经生成了代理类，而在spring-mvc.xml中，又重新扫描了一遍，使得原先cglib生成的代理子类失效，从而事务拦截也失效。
解决:
于是在spring-mvc中改成<context:component-scan base-package="cn.yzh.controller" > 只让它扫描controller，而spring-mybatis不扫描controller就好了
参考:https://blog.csdn.net/haoyifen/article/details/51172647