Uploading files with Jsp and struts

WHat is the line of the exception? Can you also post the full stack trace from Tomcat's logs?

please also post UploadAction.execute()

tomcat logs was

2004-11-17 12:41:51 StandardWrapperValve[action]: Servlet.service() for servlet action threw exception
java.lang.NullPointerException
      at ie.sentenial.application.actions.UploadAction.execute(Unknown Source)
      at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:484)
      at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:274)
      at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1482)
      at org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:507)
      at javax.servlet.http.HttpServlet.service(HttpServlet.java:743)
      at javax.servlet.http.HttpServlet.service(HttpServlet.java:856)
      at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:284)
      at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:204)
      at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:257)
      at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:151)
      at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:567)
      at org.apache.catalina.core.StandardContextValve.invokeInternal(StandardContextValve.java:245)
      at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:199)
      at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:151)
      at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:567)
      at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:184)
      at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:151)
      at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:164)
      at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:149)
      at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:567)
      at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:156)
      at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:151)
      at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:567)
      at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:972)
      at org.apache.coyote.tomcat5.CoyoteAdapter.service(CoyoteAdapter.java:206)
      at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:833)
      at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.processConnection(Http11Protocol.java:732)
      at org.apache.tomcat.util.net.TcpWorkerThread.runIt(PoolTcpEndpoint.java:619)
      at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:688)
      at java.lang.Thread.run(Thread.java:534)

2004-11-17 12:41:51 StandardWrapperValve[action]: Servlet.service() for servlet action threw exception
java.lang.NullPointerException
      at ie.sentenial.application.actions.UploadAction.execute(Unknown Source)
      at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:484)
      at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:274)
      at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1482)
      at org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:507)
      at javax.servlet.http.HttpServlet.service(HttpServlet.java:743)
      at javax.servlet.http.HttpServlet.service(HttpServlet.java:856)
      at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:284)
      at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:204)
      at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:257)
      at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:151)
      at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:567)
      at org.apache.catalina.core.StandardContextValve.invokeInternal(StandardContextValve.java:245)
      at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:199)
      at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:151)
      at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:567)
      at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:184)
      at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:151)
      at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:164)
      at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:149)
      at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:567)
      at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:156)
      at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:151)
      at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:567)
      at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:972)
      at org.apache.coyote.tomcat5.CoyoteAdapter.service(CoyoteAdapter.java:206)
      at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:833)
      at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.processConnection(Http11Protocol.java:732)
      at org.apache.tomcat.util.net.TcpWorkerThread.runIt(PoolTcpEndpoint.java:619)
      at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:688)
      at java.lang.Thread.run(Thread.java:534)

Upload action

 public ActionForward execute( ActionMapping mapping, ActionForm form, HttpServletRequest request, HttpServletResponse response )
        {
             
              
          UploadActionForm f = (UploadActionForm)form ;
          try {
                  InputStream fileInput = f.getFile().getInputStream() ;
                  // do stuff with the input stream to read the file in, then close it
            } catch (FileNotFoundException e) {
                  e.printStackTrace();
            } catch (IOException e) {
                  e.printStackTrace();
            }
        
            if(request.getParameter("action") == null || request.getParameter("action").equalsIgnoreCase(null))
            {
                  return (mapping.findForward("upload"));
            }
            else if(request.getParameter("action").equals("form"))
            {                  
                  return (mapping.findForward("upload"));
            }
            else
            {
                  return (mapping.findForward("upload"));
            }
        }

And the line the error was thrown?

i dont know what line threw the error

would prob be


 else if(request.getParameter("action").equals("form"))
          {              
               return (mapping.findForward("upload"));
          }

Ok we can start by the most obvious. Can you make sure that the file "f" is not null? Put a Systsem.out statement and see if it is null: System.out.println("f: " + f);

I'd suggest you put a few System.out statements and see what is null. Then we can go on from there.

the file should be empty at the moment becuase nothign has been uploaded yet...i get this error when i try go to the jsp that will allow a client to upload a file f

fyness,
did u defined UploadActionForm as the form bean for u action in strutsconfig.xml?
 please post ur action definition in strutsconfig.xml

yep

 <form-bean name="uploadActionForm" type="application.forms.UploadActionForm" />


  <action path="/dataUploadAction"
            type="ie.sentenial.application.actions.UploadAction"
            scope="request">
    </action>
   
    <action path="/upload"
            type="ie.sentenial.application.actions.UploadAction"
            scope="request">
    </action>

Venabili
I think I answered and deserve the Acceptance for my last comment

I also think permagdy's last comment is the valid answer.