File upload: problem with writing uploaded file to server-harddisk

Question

Hello,
according to the example in the File upload tutorial, I tried to save an uploaded file to disk, but it didn't work (and also no messages / exceptions were thrown).
The Javadoc for the function uploadedFile.write(filename) says that if the file should be written in an other directory than the servers' tmp-directory, the server.policy has to be adjusted.
The following line is already included in my server.policy:
permission java.io.FilePermission "<<ALL FILES>>", "read,write";
So I have two questions:
1) Where can I find the servers' tmp-directory?
2) How should the sever.policy permission code look like?

Answer 1

The File Upload tutorial at http://developers.sun.com/prodtech/javatools/jscreator/learning/tutorials/2/file_upload.html has you save the uploaded file to disk. It also gives this information:
The server holds the uploaded file in memory unless it exceeds 4096 bytes, in which case the server holds the file contents in a temporary file. You can change this threshold by modifying the sizeThreshold parameter for the UploadFilter filter entry in the web application's web.xml file. For more information on modifying the web.xml file, see the last section in this tutorial, Doing More: Modifying the Maximum File Upload Size.
In cases where you want to retain the uploaded file, you have three choices:
* Write the file to a location of your choosing, as shown in this tutorial.
* Create an UploadedFile property in a managed bean and set it to the component's value before you exit the page (as in the button's action method).
* Save the file to a database.
By default, the File Upload component can handle files up to one megabyte in size. You can change the maximum file size by modifying the maxSize parameter for the UploadFilter filter entry in the application's web.xml file, as described in the last section in this tutorial, Doing More: Modifying the Maximum File Upload Size.