MyBatis的TooManyResultsException异常的解决办法

今日再开发遇到了这样的一个异常：Expected one result (or null) to be returned by selectOne(), but found: 2

详细的异常信息如下：

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59

2017 - 03 - 31 15 : 44 : 24 , 640 ERROR method : com . baikeyang . bapi . modules . user . service . impl . LoginServiceImpl . login ( LoginServiceImpl . java : 156 ) -用户登录时发生异常 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      at org . mybatis . spring . MyBatisExceptionTranslator . translateExceptionIfPossible ( MyBatisExceptionTranslator . java : 76 )      at org . mybatis . spring . SqlSessionTemplate $ SqlSessionInterceptor . invoke ( SqlSessionTemplate . java : 399 )      at com . sun . proxy . $ Proxy13 . selectOne ( Unknown Source )      at org . mybatis . spring . SqlSessionTemplate . selectOne ( SqlSessionTemplate . java : 165 )      at org . apache . ibatis . binding . MapperMethod . execute ( MapperMethod . java : 63 )      at org . apache . ibatis . binding . MapperProxy . invoke ( MapperProxy . java : 43 )      at com . sun . proxy . $ Proxy14 . selectAlarmCountData ( Unknown Source )      at com . baikeyang . bapi . modules . alarm . service . impl . AlarmServiceImpl . getAlarmCountData ( AlarmServiceImpl . java : 25 )      at com . baikeyang . bapi . modules . user . service . impl . LoginServiceImpl . getAlarmCountData ( LoginServiceImpl . java : 185 )      at com . baikeyang . bapi . modules . user . service . impl . LoginServiceImpl . login ( LoginServiceImpl . java : 131 )      at com . baikeyang . bapi . web . controller . LoginController . login ( LoginController . java : 39 )      at sun . reflect . GeneratedMethodAccessor103 . invoke ( Unknown Source )      at sun . reflect . DelegatingMethodAccessorImpl . invoke ( DelegatingMethodAccessorImpl . java : 25 )      at java . lang . reflect . Method . invoke ( Method . java : 597 )      at org . springframework . web . method . support . InvocableHandlerMethod . doInvoke ( InvocableHandlerMethod . java : 221 )      at org . springframework . web . method . support . InvocableHandlerMethod . invokeForRequest ( InvocableHandlerMethod . java : 137 )      at org . springframework . web . servlet . mvc . method . annotation . ServletInvocableHandlerMethod . invokeAndHandle ( ServletInvocableHandlerMethod . java : 110 )      at org . springframework . web . servlet . mvc . method . annotation . RequestMappingHandlerAdapter . invokeHandleMethod ( RequestMappingHandlerAdapter . java : 776 )      at org . springframework . web . servlet . mvc . method . annotation . RequestMappingHandlerAdapter . handleInternal ( RequestMappingHandlerAdapter . java : 705 )      at org . springframework . web . servlet . mvc . method . AbstractHandlerMethodAdapter . handle ( AbstractHandlerMethodAdapter . java : 85 )      at org . springframework . web . servlet . DispatcherServlet . doDispatch ( DispatcherServlet . java : 959 )      at org . springframework . web . servlet . DispatcherServlet . doService ( DispatcherServlet . java : 893 )      at org . springframework . web . servlet . FrameworkServlet . processRequest ( FrameworkServlet . java : 967 )      at org . springframework . web . servlet . FrameworkServlet . doPost ( FrameworkServlet . java : 869 )      at javax . servlet . http . HttpServlet . service ( HttpServlet . java : 643 )      at org . springframework . web . servlet . FrameworkServlet . service ( FrameworkServlet . java : 843 )      at javax . servlet . http . HttpServlet . service ( HttpServlet . java : 723 )      at org . apache . catalina . core . ApplicationFilterChain . internalDoFilter ( ApplicationFilterChain . java : 290 )      at org . apache . catalina . core . ApplicationFilterChain . doFilter ( ApplicationFilterChain . java : 206 )      at org . springframework . web . filter . HiddenHttpMethodFilter . doFilterInternal ( HiddenHttpMethodFilter . java : 77 )      at org . springframework . web . filter . OncePerRequestFilter . doFilter ( OncePerRequestFilter . java : 107 )      at org . apache . catalina . core . ApplicationFilterChain . internalDoFilter ( ApplicationFilterChain . java : 235 )      at org . apache . catalina . core . ApplicationFilterChain . doFilter ( ApplicationFilterChain . java : 206 )      at com . baikeyang . bapi . filter . MethodFilter . doFilter ( MethodFilter . java : 66 )      at org . apache . catalina . core . ApplicationFilterChain . internalDoFilter ( ApplicationFilterChain . java : 235 )      at org . apache . catalina . core . ApplicationFilterChain . doFilter ( ApplicationFilterChain . java : 206 )      at org . springframework . web . filter . CharacterEncodingFilter . doFilterInternal ( CharacterEncodingFilter . java : 85 )      at org . springframework . web . filter . OncePerRequestFilter . doFilter ( OncePerRequestFilter . java : 107 )      at org . apache . catalina . core . ApplicationFilterChain . internalDoFilter ( ApplicationFilterChain . java : 235 )      at org . apache . catalina . core . ApplicationFilterChain . doFilter ( ApplicationFilterChain . java : 206 )      at org . apache . catalina . core . StandardWrapperValve . invoke ( StandardWrapperValve . java : 233 )      at org . apache . catalina . core . StandardContextValve . invoke ( StandardContextValve . java : 191 )      at org . apache . catalina . core . StandardHostValve . invoke ( StandardHostValve . java : 127 )      at org . apache . catalina . valves . ErrorReportValve . invoke ( ErrorReportValve . java : 103 )      at org . apache . catalina . core . StandardEngineValve . invoke ( StandardEngineValve . java : 109 )      at org . apache . catalina . connector . CoyoteAdapter . service ( CoyoteAdapter . java : 293 )      at org . apache . coyote . http11 . Http11AprProcessor . process ( Http11AprProcessor . java : 879 )      at org . apache . coyote . http11 . Http11AprProtocol $ Http11ConnectionHandler . process ( Http11AprProtocol . java : 610 )      at org . apache . tomcat . util . net . AprEndpoint $ Worker . run ( AprEndpoint . java : 1777 )      at java . lang . Thread . run ( Thread . java : 662 ) Caused by : org . apache . ibatis . exceptions . TooManyResultsException : Expected one result ( or null ) to be returned by selectOne ( ) , but found : 2      at org . apache . ibatis . session . defaults . DefaultSqlSession . selectOne ( DefaultSqlSession . java : 66 )      at sun . reflect . GeneratedMethodAccessor89 . invoke ( Unknown Source )      at sun . reflect . DelegatingMethodAccessorImpl . invoke ( DelegatingMethodAccessorImpl . java : 25 )      at java . lang . reflect . Method . invoke ( Method . java : 597 )      at org . mybatis . spring . SqlSessionTemplate $ SqlSessionInterceptor . invoke ( SqlSessionTemplate . java : 386 )      . . . 48 more

从上面的异常信息，可以了解到下面两种情况：

1.你想查询一条数据，但返回两条数据：

2.你想查询多条数据，但是前台限制只能查询一条

(1) 检查自己的数据sql语句写对没有（关于mybaties的sql操作自己百度）

(2) 查看mybaties的返回值（resultType或resultMap），可以返回list，map等数据

(3)  dao层接口要与mybaties中返回值和接收值都要保持一致

例：返回map数据

返回多条数据是多个Map，多个Map放在List中用List<Map<String,String>>接收返回数据

Mybatis返回的Map是这样的一种格式：Map<字段名称，字段值>

一个Map<字段名，字段值>对象代表一行数据

原解决方法博文地址：http://www.cnblogs.com/zcleilei/p/6245617.html