I've been working on this for hours :
When a button is pressed I need to generate XML and download it to the user. I've tried using primefaces StreamedContent with p:fileDownload - but the only output I ever get is the .xhtml source of the actual page. I can use log statements to display the contents of the the StreamedContent before returning it and I can see my XML code correctly there, but the downloaded file always has the page source instead. (I've tried lots of other ways as well, tied downloading a jpg file, changing the bean to generate a response directly and calling the method through the action in the h:commandButton - always get the page source!).
Here's my .xhtml :
<p:commandButton value="Create XML Bid/Offer"
id="createXMLButton"
disabled="#{portfolioBean.noPortfolioSelected}"
ajax="false"
icon="ui-icon-arrowthichk-s">
<p:fileDownload value="#{portfolioBean.order}" />
</p:commandButton>
(alternate)
<h:commandButton value="Create XML Bid/Offer"
id="createXMLButton"
disabled="#{portfolioBean.noPortfolioSelected}"
ajax="false"
icon="ui-icon-arrowthichk-s"
action="#{portfolioBean.download()}" />
And the backing bean methods :
public StreamedContent getOrder() {
...
}
(alternate)
public String download() {
...
}
I haven't included the method bodies because I know they return proper XML... it really seems to be something in the JSF magic. Is this a configuration issue or something?
Thanks!
UPDATE OK - I've stripped everything out of my code so it's just this :
<?xml version='1.0' encoding='UTF-8' ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:f="http://java.sun.com/jsf/core"
xmlns:h="http://java.sun.com/jsf/html"
xmlns:p="http://primefaces.org/ui">
<h:head>
<title>Edison Energy Portal</title>
</h:head>
<h:body>
<h:form id="form">
<h:commandButton value="Download PDF" action="#{downloadJPG.downloadFile}" />
</h:form>
</h:body>
</html>
public class DownloadJPG {
// Constants ----------------------------------------------------------------------------------
private static final int DEFAULT_BUFFER_SIZE = 10240; // 10KB.
// Actions ------------------------------------------------------------------------------------
public void downloadFile() throws IOException {
// Prepare.
FacesContext facesContext = FacesContext.getCurrentInstance();
ExternalContext externalContext = facesContext.getExternalContext();
HttpServletResponse response = (HttpServletResponse) externalContext.getResponse();
File file = new File("....", "....");
BufferedInputStream input = null;
BufferedOutputStream output = null;
try {
// Open file.
input = new BufferedInputStream(new FileInputStream(file), DEFAULT_BUFFER_SIZE);
// Init servlet response.
response.reset();
response.setHeader("Content-Type", "application/pdf");
response.setHeader("Content-Length", String.valueOf(file.length()));
response.setHeader("Content-Disposition", "inline; filename=\"...\"");
output = new BufferedOutputStream(response.getOutputStream(), DEFAULT_BUFFER_SIZE);
// Write file contents to response.
byte[] buffer = new byte[DEFAULT_BUFFER_SIZE];
int length;
while ((length = input.read(buffer)) > 0) {
output.write(buffer, 0, length);
}
// Finalize task.
output.flush();
} finally {
// Gently close streams.
close(output);
close(input);
}
// Inform JSF that it doesn't need to handle response.
// This is very important, otherwise you will get the following exception in the logs:
// java.lang.IllegalStateException: Cannot forward after response has been committed.
facesContext.responseComplete();
}
// Helpers (can be refactored to public utility class) ----------------------------------------
private static void close(Closeable resource) {
if (resource != null) {
try {
resource.close();
} catch (IOException e) {
// Do your thing with the exception. Print it, log it or mail it. It may be useful to
// know that this will generally only be thrown when the client aborted the download.
e.printStackTrace();
}
}
}
}
I've checked my source image file and it's not corrupt. BalusC's code worked for a single try, then I substituted and XML file for the current jpg, changed the MIME type and nothing has worked since. It's as if something bad has tripped in tomcat and I can't get it out or reset it (I've tried cleaning tomcat through eclipse, manually, even rebooted my box).
this is a real poser.
UPDATE : I've started eclipse clean - no luck. I'm really out of ideas. I have to think this is a configuration somewhere, because I know this code can work (I've seen it).
