SpringMVC file download

This post shows how to download a file using Spring MVC. For example, you have a SpringMVC web app and you want to include a link on a page that downloads a file to be opened on the user’s machine (e.g. a Microsoft Excel).

The code is as follows:

    @RequestMapping(value = "/Excel", method = RequestMethod.GET)
    public void handleFileDownload(HttpServletResponse res) {
        try {
            String fn = "/Test.xls";
            URL url = getClass().getResource(fn);
            File f = new File(url.toURI());
            System.out.println("Loading file "+fn+"("+f.getAbsolutePath()+")");
            if (f.exists()) {
                res.setContentType("application/xls");
                res.setContentLength(new Long(f.length()).intValue());
                res.setHeader("Content-Disposition", "attachment; filename=Test.xls");
                FileCopyUtils.copy(new FileInputStream(f), res.getOutputStream());
            } else {
                System.out.println("File"+fn+"("+f.getAbsolutePath()+") does not exist");
            }
        } catch (Exception e) {
            System.out.println(e.getMessage());
        }
    }

Where:

• “/Excel” is an arbitrary path name (can be anything)
• “Test.xls” resides in src/main/resources

The code uses Spring’s own FileCopyUtils for making the file available.
The complete maven project can be found here on github.

(Previously I had the code deployed on a CloudBees instance at http://springmvc-filedownload.shaunabram.cloudbees.net, but CloudBees have since unfortunately shut down their free tier)

Tags: spring, springmvc