Download file with JSF

Question

everyone!

I have a trouble. I tried to save excel file in jsf web application. I generated file by my utils and trying to get "save" window, but I failed.

Here is my code:

  <div>
  <h:commandButton value="Apply" actionListener="#{hornPhonesBean.generateReport}"/>
  </div>

and:

   public void generateReport(ActionEvent event) {
    System.out.println("GENERATE REPORT FROM = " + this.dateFrom + "; TO = " + this.dateTo);

    try {
        XSSFWorkbook workbook = (XSSFWorkbook) HornReportGenerator.getWorkbook(null, null);
        String fileName = "1.xlsx";

        FacesContext fc = FacesContext.getCurrentInstance();
        ExternalContext ec = fc.getExternalContext();

        // Some JSF component library or some Filter might have set some headers in the buffer beforehand. We want to get rid of them, else it may collide.
        ec.responseReset(); 

        // Check http://www.w3schools.com/media/media_mimeref.asp for all types. Use if necessary ExternalContext#getMimeType() for auto-detection based on filename.
        ec.setResponseContentType("application/vnd.ms-excel"); 

        // Set it with the file size. This header is optional. It will work if it's omitted, but the download progress will be unknown.
        //ec.setResponseContentLength(contentLength); 

        // The Save As popup magic is done here. You can give it any file name you want, this only won't work in MSIE, it will use current request URL as file name instead.
        ec.setResponseHeader("Content-Disposition", "attachment; filename=\"" + fileName + "\""); 

        OutputStream output = ec.getResponseOutputStream();
        workbook.write(output); 
        output.flush();
        output.close();

        fc.responseComplete(); // Important! Otherwise JSF will attempt to render the response which obviously will fail since it's already written with a file and closed.
        System.out.println("END");
    } catch (Exception e) {
        e.printStackTrace();
    }
}

I read suggestions here and from another forums - everyone says I shouldnt use , but I didn't use it at all.

Then I thought that the problem could be in the

 <ice:form>, 

where I kept the

 <h:commandButton>, 

and I changed to

 <h:form>, 

but it didn't help.

Maybe the problem in the request - it has header Faces-Request partial/ajax. But I am not sure.

Please give me some ideas - I already spent 4 hours for this crazy jsf download issue)

Answer 1

Maybe the problem in the request - it has header Faces-Request partial/ajax. But I am not sure.

This suggests that the request is an ajax request. You can't download files by ajax. Ajax requests are processed by JavaScript which has for obvious security reasons no facilities to programmatically pop a Save As dialogue nor to access/manipulate client's disk file system.

Your code snippet does however not show that you're using ajax. Perhaps you oversimplified it too much or you're using ICEfaces which silently auto-enables ajax on all standard JSF command components.

In any case, you need to make sure that it's not sending an ajax request.

See also:

• How to provide a file download from a JSF backing bean?
• ICEfaces libary in classpath prevents Save As dialog from popping up on file download