不定数量附件上传

Question

<form-beans>
<form-bean name="upFileForm" type="org.apache.struts.action.DynaActionForm">
<form-property name="fileh" type="org.apache.struts.upload.FormFile" />
</form-bean></form-beans>
public ActionForward saveMailExecute(ActionMapping mapping, ActionForm form,
 HttpServletRequest request, HttpServletResponse response) {
 DynaActionForm upFileForm = (DynaActionForm) form;
 String dirPath = getServlet().getServletContext().getRealPath("/") + "upload";
 Hashtable fileh = upFileForm.getMultipartRequestHandler().getFileElements();
 System.out.println("test");
 for (Enumeration e = fileh.keys(); e.hasMoreElements();) {
 String key = (String) e.nextElement();
 try {
 FormFile formfile = (FormFile) fileh.get(key);
 String filename = formfile.getFileName().trim();
 if (!"".equals(filename)) {
 InputStream ins = formfile.getInputStream();
 OutputStream os = new FileOutputStream(dirPath + java.io.File.separatorChar + filename);
 System.out.println(dirPath + java.io.File.separatorChar + filename);
 int bytesRead = 0;
 byte[] buffer = new byte[8192];
 while ((bytesRead = ins.read(buffer, 0, 8192)) != -1) {
 os.write(buffer, 0, bytesRead);
 }
 os.close();
 ins.close();
 }
 } catch (Exception ex) {
 }
 }
 return mapping.findForward("sendMail");
 }2008-05-23 15:02:55,375  WARN [http-8088-Processor24] (org.apache.struts.action.RequestProcessor:507) - Unhandled Exception thrown: class java.lang.NullPointerException
2008-05-23 15:02:55,390 ERROR [http-8088-Processor24] (org.apache.catalina.core.ContainerBase.[Catalina].[localhost].[/flaunt].[action]:253) - Servlet.service() for servlet action threw exception
java.lang.NullPointerException
at com.systemset.MailAction.saveMailExecute(MailAction.java:116)
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.apache.struts.actions.DispatchAction.dispatchMethod(DispatchAction.java:274)
at org.apache.struts.actions.DispatchAction.execute(DispatchAction.java:194)
at com.common.BaseDispatchAction.execute(BaseDispatchAction.java:33)
at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:419)
at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:224)
at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1192)
at org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:430)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:709)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:252)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:107)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:869)
at org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:664)
at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:527)
at org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:80)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684)
at java.lang.Thread.run(Unknown Source)Hashtable fileh = upFileForm.getMultipartRequestHandler().getFileElements();
这个地方始终只能取到null，不知道为什么？在线等。

Answer 1

前台页面设置传输数据的格式了么？<form action="" methoed="post" enctype="multipart/form-data">
method="post"大数量附件上传

Answer 2

NullPointerException 空指针异常看看MailAction.java:116 这样是什么。 检查一下有没有可能出现null的情况

Answer 3

用的是<form action="" methoed="post" enctype="multipart/form-data"> 
只是这个地方始终是null.
116行是Hashtable fileh = upFileForm.getMultipartRequestHandler().getFileElements();