Exception with Download Action

When trying to implement Download Action, I got this exception. Can some one help please ? 2005-08-21 20:14:15 StandardWrapperValve[docAction]: Servlet.service() for servlet docAction threw exception java.lang.NullPointerException at org.apache.struts.actions.DownloadAction.copy (DownloadA

Struts Download Action

Hi All, I'm developing a web application based on Struts. In this, one of the features to be included is , to download a file, when the user clicks on the link in the JSP page. Also, when the user clicks on the link, the Save/Open dialog box should appear. If nyone has used the DownloadAction pr