Error when downloading file to browser
todd.nash Feb 1, 2008 10:17 PMI would really appreciate some answers on this one...
I have a page that allows the user to download a file that is stored in the database as a BLOB. The following exception is thrown when the download link is clicked. I can trace through my method to the point where the reponse is returning through the Seam filters, so I know that the method is returning the bytes associated with the file.
java.lang.IllegalStateException: Servlet response already use stream, Writer not possible at org.ajax4jsf.webapp.FilterServletResponseWrapper.getWriter(FilterServletResponseWrapper.java:226) at javax.servlet.ServletResponseWrapper.getWriter(ServletResponseWrapper.java:112) at javax.servlet.ServletResponseWrapper.getWriter(ServletResponseWrapper.java:112) at javax.servlet.ServletResponseWrapper.getWriter(ServletResponseWrapper.java:112) at com.sun.facelets.FaceletViewHandler.createResponseWriter(FaceletViewHandler.java:414) at com.sun.facelets.FaceletViewHandler.renderView(FaceletViewHandler.java:571) at org.ajax4jsf.application.ViewHandlerWrapper.renderView(ViewHandlerWrapper.java:108) at org.ajax4jsf.application.AjaxViewHandler.renderView(AjaxViewHandler.java:216) at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:106) at com.sun.faces.lifecycle.LifecycleImpl.phase(LifecycleImpl.java:251) at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:144) ...
My page looks like this:
<h:panelGrid id="document" columns="2"> <h:outputLabel value="Location"/> <h:outputText value="#{documentLocation.location}"/> <h:outputLabel value="Upload Date"/> <h:outputText value="#{documentLocation.uploadDate}"/> <h:outputLabel value="Content Type"/> <h:outputText value="#{documentLocation.contentType}"/> <h:outputLabel value="Description"/> <h:outputText value="#{documentLocation.notes}"/> <h:panelGroup> <s:link id="downloadDocument" value="Download" action="#{documentManager.onDownload}" view="/download.xhtml"> <f:param name="docId" value="#{documentLocation.id}"/> </s:link> </h:panelGroup> </h:panelGrid>
The onDownload method looks like this:
public String onDownload() { System.out.println( "DocumentManagerAction.onDownload() called" ); System.out.println( "Value of doc id is " + docId ); HttpServletResponse response = ( HttpServletResponse ) facesContext.getExternalContext().getResponse(); response.setContentType( "application/pdf" ); try { byte[] docData = getDocumentData(); if ( docData != null && docData.length > 0 ) { response.setContentLength( docData.length ); os.write( docData ); os.flush(); os.close(); System.out.println( "\nSuccess\n" ); } facesContext.responseComplete(); } catch ( Exception e ) { System.out.println( "\nFailure : " + e.toString() + "\n" ); return null; } return "done"; }