Struts 1.2 中文件上传抛异常

使用Struts 1.2 进行文件上传的时候总是抛出相同的异常

2010-6-11 15:57:53 org.apache.commons.beanutils.PropertyUtilsBean invokeMethod
严重: Method invocation failed.
java.lang.IllegalArgumentException: argument type mismatch
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.commons.beanutils.PropertyUtilsBean.invokeMethod(PropertyUtilsBean.java:1773)
at org.apache.commons.beanutils.PropertyUtilsBean.setSimpleProperty(PropertyUtilsBean.java:1759)
at org.apache.commons.beanutils.PropertyUtilsBean.setNestedProperty(PropertyUtilsBean.java:1648)
at org.apache.commons.beanutils.PropertyUtilsBean.setProperty(PropertyUtilsBean.java:1677)
at org.apache.commons.beanutils.BeanUtilsBean.setProperty(BeanUtilsBean.java:1022)
at org.apache.commons.beanutils.BeanUtilsBean.populate(BeanUtilsBean.java:811)
at org.apache.commons.beanutils.BeanUtils.populate(BeanUtils.java:298)
at org.apache.struts.util.RequestUtils.populate(RequestUtils.java:493)
at org.apache.struts.action.RequestProcessor.processPopulate(RequestProcessor.java:816)
at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:203)
at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196)
at org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:432)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:637)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
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:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
at org.apache.coyote.http11.Http11AprProcessor.process(Http11AprProcessor.java:859)
at org.apache.coyote.http11.Http11AprProtocol$Http11ConnectionHandler.process(Http11AprProtocol.java:579)
at org.apache.tomcat.util.net.AprEndpoint$Worker.run(AprEndpoint.java:1555)
at java.lang.Thread.run(Thread.java:619)
2010-6-11 15:57:53 org.apache.catalina.core.StandardWrapperValve invoke
严重: Servlet.service() for servlet action threw exception
java.lang.IllegalArgumentException: Cannot invoke kevin.actionForm.UpLoadActionForm.setFileName - argument type mismatch
at org.apache.commons.beanutils.PropertyUtilsBean.invokeMethod(PropertyUtilsBean.java:1778)
at org.apache.commons.beanutils.PropertyUtilsBean.setSimpleProperty(PropertyUtilsBean.java:1759)
at org.apache.commons.beanutils.PropertyUtilsBean.setNestedProperty(PropertyUtilsBean.java:1648)
at org.apache.commons.beanutils.PropertyUtilsBean.setProperty(PropertyUtilsBean.java:1677)
at org.apache.commons.beanutils.BeanUtilsBean.setProperty(BeanUtilsBean.java:1022)
at org.apache.commons.beanutils.BeanUtilsBean.populate(BeanUtilsBean.java:811)
at org.apache.commons.beanutils.BeanUtils.populate(BeanUtils.java:298)
at org.apache.struts.util.RequestUtils.populate(RequestUtils.java:493)
at org.apache.struts.action.RequestProcessor.processPopulate(RequestProcessor.java:816)
at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:203)
at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196)
at org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:432)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:637)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
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:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
at org.apache.coyote.http11.Http11AprProcessor.process(Http11AprProcessor.java:859)
at org.apache.coyote.http11.Http11AprProtocol$Http11ConnectionHandler.process(Http11AprProtocol.java:579)
at org.apache.tomcat.util.net.AprEndpoint$Worker.run(AprEndpoint.java:1555)
at java.lang.Thread.run(Thread.java:619)

本人刚开始接触Struts 不知道该怎么解决~~~~~~