每日一个知识点5 2014/6/3



运行环境：mybatis，java，extjs

<if test="treeType == ‘S’ ">
and tree_type='S'
 </if>
 <if test=”treeType!=null and treeType!=‘’ and treeType!=‘S’ “>
and tree_type != 'S'
 </if>

报错：

org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.exceptions.PersistenceException:
### Error querying database.  Cause: java.lang.NumberFormatException: For input string: "S"
### Cause: java.lang.NumberFormatException: For input string: "S"
 at org.mybatis.spring.MyBatisExceptionTranslator.translateExceptionIfPossible(MyBatisExceptionTranslator.java:75)
 at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:371)
 at com.sun.proxy.$Proxy8.selectOne(Unknown Source)
 at org.mybatis.spring.SqlSessionTemplate.selectOne(SqlSessionTemplate.java:163)
 at com.forlink.tany.entity.PageQuery.queryWithSqlID(PageQuery.java:33)
 at com.forlink.tany.entity.PageQuery.queryWithSqlID(PageQuery.java:24)
 at com.forlink.tany.adminWeb.salManage.market.ReturnGoodsCheck.query(ReturnGoodsCheck.java:214)
 at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
 at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
 at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
 at java.lang.reflect.Method.invoke(Unknown Source)
 at org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:175)
 at org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:446)
 at org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:434)
 at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:938)
 at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:870)
 at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:961)
 at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:852)
 at javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
 at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:837)
 at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
 at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)
 at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:108)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
 at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:225)
 at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:169)
 at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
 at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168)
 at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98)
 at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:927)
 at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
 at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407)
 at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:999)
 at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:565)
 at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:309)
 at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(Unknown Source)
 at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
 at java.lang.Thread.run(Unknown Source)

解决方法：

1.<if test="treeType == &quot;S&quot; ">
and tree_type='S'
 </if>

2.<if test='treeType!=null and treeType!="" and treeType!="S" '>
and tree_type != 'S'
 </if>

（原因是OGNL语法的问题：
这里 'S' 将被认为是 char 类型，但是 'SS' 或者 "S" 将被作为 String类型

‘’和“”换着用）