October 03, 2009

Easy file upload in Java using Jersey and Uploadify

Uploading a bunch of files to your server. I have come across this particular requirement a few times now during my web development career, but only recently did I discover a very easy way to implement it. And by easy I mean easy on both the client side and the server side.


On the server side we develop our web applications in Java using Glassfish for our deployement server. You can have your standard Servlet class that catches your requests, but recently we bumped into Jersey. And I must say, I really love it. Here is for example the code to accept a file upload request.

public class FileHandler {
public String uploadFile(@FormParam("file") File file, @FormParam("file") FormDataContentDisposition fcdsFile) {
String fileLocation = "/files/" + fcdsFile.getFileName();
File destFile = new File(fileLocation);

// your code here to copy file to destFile

return "1";

That's it. The FormDataContentDisposition is a recent addition to Jersey which allows you to retrieve the name of the file that is being uploaded.


For the client side, I decided to make use of Uploadify. They basically provided a wrapper around SWFUpload using JQuery. Here is the code I used on the client side:

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<script type="text/javascript" src="js/swfobject.js"></script>
<script type="text/javascript" src="js/jquery-1.3.2.min.js"></script>
<script type="text/javascript" src="js/jquery.uploadify.v2.1.0.min.js"></script>
<link rel="stylesheet" href="css/uploadify.css" type="text/css" media="screen"/>

<script type="text/javascript">
$(function() {
'uploader' : 'swf/uploadify.swf',
'script' : 'rest/file/upload',
'fileDataName' : 'file',
'cancelImg' : 'img/cancel.png',
'multi' : true
<h1>Simple File Upload</h1>

<h3>Multiple file upload made easy</h3>

<div id="file_upload"></div>
<input type="button" value="Clear Queue" onclick="$('#file_upload').uploadifyClearQueue();"/>
<input type="button" value="Submit Queue" onclick="$('#file_upload').uploadifyUpload();"/>

Voila, now you have a simple web application that is able to upload files to your server. You can download a sample application here.