Uploadedfile does not retain its value

Question

Hi,
I am using the following to upload a Excel file:
*<af:inputFile label="File to Upload" columns="30" value="#{backing_dataUpload.file}"/>*
Here is how I 'put' save the file for later use, in hte sesion:
**public void processExcelHeader() {**
UploadedFile file = getFile();
AdfFacesContext.getCurrentInstance().getViewScope().put("uploadedFileKey",file);//
Here is how I retrieve it:
*public void beginUpload() {//=======TBD=======*
UploadedFile uploadFile = (UploadedFile)AdfFacesContext.getCurrentInstance().getViewScope().get("uploadedFileKey");
if (uploadFile != null)
*try {*
ProcessExcelWorksheet pexcel = new ProcessExcelWorksheet();
java.io.InputStream in = uploadFile.getInputStream();
PROBLEM is the value java.io.InputStream in returns NULL. PLease note that the scope tof the Bean is 'Session'.
I Looked into the debugger the 'uploadFile' in hte beginUpload() has all the entries except the 'buffer' is NULL, and hte length is zero.
Please note that after the out there is some processing and the control exits back to screen, and on pressing another Command Button it returns to the
beginUoload() function.
Any Ideas......
Thanks......

Answer 1

Anil:
No, I don't think the 2 backing bean method is out of scope. I guess the framework implicitly close the stream in the first event handler. Because the framework might think you're done with it. After all the Session scope is the second largest scope and only shorter than Application scope.
The behavior may be related how the framework dispatch the servicing back bean to handle your event. Even thoug it might be using the same backing bean instance, the framework may clean it up after the completion of each round of servicing.
Your probably need to put the instance of the opened InputStream into ViewScope so that the inputstream will not be closed since it is still referenced. But you need to remember to close it after using in the second method which is beginUpload().
So in
public void processExcelHeader() {**
UploadedFile file = getFile();
InputStream is = file.getInputStream();
AdfFacesContext.getCurrentInstance().getViewScope().put("uploadedFileStream",is);//
Then:
public void beginUpload() {//=======TBD=======
InputStream inputStream = (UploadedFile)AdfFacesContext.getCurrentInstance().getViewScope().get("uploadedFileStream");
inputStream.close();
If you don't close it after using, you should experience serious memory leak.
Good luck,
Alex