mysql5.7之后开始支持json数据格式类型。
但是mybaits暂时不支持。逆向工程生成的entity的字段类型为object。
保存数据的时候报如下错误：

### Cause: com.mysql.jdbc.MysqlDataTruncation: Data truncation: Cannot create a JSON value from a string with CHARACTER SET 'binary'.
; SQL []; Data truncation: Cannot create a JSON value from a string with CHARACTER SET 'binary'.; nested exception is com.mysql.jdbc.MysqlDataTruncation: Data truncation: Cannot create a JSON value from a string with CHARACTER SET 'binary'.
    at org.springframework.jdbc.support.SQLStateSQLExceptionTranslator.doTranslate(SQLStateSQLExceptionTranslator.java:102)
    at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:73)
    at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:82)
    at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:82)
    at org.mybatis.spring.MyBatisExceptionTranslator.translateExceptionIfPossible(MyBatisExceptionTranslator.java:75)
    at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:447)
    at com.sun.proxy.$Proxy74.insert(Unknown Source)
    at org.mybatis.spring.SqlSessionTemplate.insert(SqlSessionTemplate.java:279)
    at org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:56)
    at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:53)
    at com.sun.proxy.$Proxy85.insertSelective(Unknown Source)
    at com.vipcode.vts.service.Impl.HourMaterialServiceImpl.infoAdd(HourMaterialServiceImpl.java:298)
    at com.vipcode.vts.controller.HourMaterialController.infoAdd(HourMaterialController.java:78)
    at com.vipcode.vts.controller.HourMaterialController$$FastClassBySpringCGLIB$$a700d48f.invoke(<generated>)
    at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204)
    at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:736)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157)
    at org.springframework.aop.framework.adapter.MethodBeforeAdviceInterceptor.invoke(MethodBeforeAdviceInterceptor.java:52)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
    at org.springframework.aop.framework.adapter.AfterReturningAdviceInterceptor.invoke(AfterReturningAdviceInterceptor.java:52)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)

解决办法：
将生成的entity的object类型改成string。