1、java.lang.ClassCastException: com.chenggutek.iou.rest.modular.comm.entity.MsgUser cannot be cast to （转换异常）com.baomidou.mybatisplus.plugins.Page
at com.sun.proxy.$Proxy90.getPageMsgTrade(Unknown Source) ~[na:na]
2、org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.binding.BindingException: Parameter 'app_user_id' not found. Available parameters are [appUserId, param1]
原因：xml文件中，param参数错误，不对应和Mapper.java
3、org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.exceptions.TooManyResultsException: Expected one result (or null) to be returned by selectOne(), but found: 2（结果应该为一个，但是却查到了两个）
at org.mybatis.spring.MyBatisExceptionTranslator.translateExceptionIfPossible(MyBatisExceptionTranslator.java:77) ~[mybatis-spring-1.3.1.jar:1.3.1]
4、org.springframework.dao.TransientDataAccessResourceException:
### Error updating database. Cause: java.sql.SQLException: Connection is read-only. Queries leading to data modification are not allowed
### The error may involve com.chenggutek.iou.rest.modular.pay.dao.PayOrderMapper.insert-Inline
### The error occurred while setting parameters
### SQL: INSERT INTO tbl_pay_order ( trade_id ) VALUES ( ? )
### Cause: java.sql.SQLException: Connection is read-only. Queries leading to data modification are not allowed
; SQL []; Connection is read-only. Queries leading to data modification are not allowed; nested exception is java.sql.SQLException: Connection is read-only. Queries leading to data modification are not allowed
今天更新数据时出现这个错误：
java.sql.SQLException: Connection is read-only. Queries leading to data modification are not allowed
原因：我在service层设置了只读。@Transactional(readOnly = true)
而更新的方法没有把可读设置为FALSE。解决办法是在方法上加上readOnly=FALSE
注解如下： @Transactional(readOnly = false, isolation = Isolation.DEFAULT, propagation = Propagation.REQUIRED)
5、Required request body is missing ：public org.springframework.http.ResponseEntity ……
原因：没有传参
6、.m.m.a.ExceptionHandlerExceptionResolver : Resolved exception caused by Handler execution: org.springframework.web.method.annotation.MethodArgumentTypeMismatchException: Failed to convert value of type 'java.lang.String' to required type 'java.lang.Integer'; nested exception is java.lang.NumberFormatException: For input string: "undefined"
原因：调用的方法id对不上号，js错误
