Comments on: Minify all your JavaScript and Stylsheets automatically with YUI Compressor and a Servlet Filter

By: ELahti

ELahti — Wed, 20 May 2009 04:20:23 +0000

Nice post! I also use Javascript Obfuscator, http://javascript-source.com/, it has two time better compression ration than YUI Compressor

By: Jordi Hernandez

Jordi Hernandez — Tue, 05 Feb 2008 18:07:28 +0000

Hi! I have published a java library that does all this and more for you, called Jawr. It is a solution that adds zero processing overhead to requests and supports gzipping and combination of js (and CSS) files. Compression is done by means of JSMin. You can check it out at https://jawr.dev.java.net/

By: sungkwon.eom

sungkwon.eom — Thu, 17 Jan 2008 07:40:13 +0000

thanks for excellent tip.
However I got some trouble.

InputStream inputStream = context.getResourceAsStream(requestURI);
==> here, inoutSteam is null.
FYI, requetedURI is “/static/global/css/ng-global.css”.
And I’m using spring MVC framework.
What is wrong?

By: Steven Jardine

Steven Jardine — Fri, 02 Nov 2007 14:42:21 +0000

Thanks for this information! I had to make some changes in order to add support for chaining. This way it is possible to add other filters after this one. This example works great as long as this filter is the last on in the list.

Anyway, if you would like to see my example let me know and I will send it to you.

By: Jeroen van Wilgenburg

Jeroen van Wilgenburg — Tue, 11 Sep 2007 19:39:14 +0000

Good remark Mathias! It felt kind of wrong using something with a lower case t, so now I have a working (and better looking ) solution.

By: Jeroen van Wilgenburg

Jeroen van Wilgenburg — Tue, 11 Sep 2007 10:32:56 +0000

Thanks for your tips Patrick. The header will improve performance, I’m going to find out how to do it in Tomcat. I think I can change the headers in the servlet filter. I’m not sure whether GZip will improve client side performance, but I also will give that a try. I’m affraid unzipping takes more time than transferring the extra bytes.

By: Jacob Hookom

Jacob Hookom — Mon, 10 Sep 2007 17:33:22 +0000

I’m not sure why you would need to run though content-specific compression over general gzip (agreeing with Patrick). It seems like code-specific compression would be an extra variable and added overhead when Gzip is content agnostic and is supported by all browsers.

By: Mathias Bogaert

Mathias Bogaert — Sun, 09 Sep 2007 22:19:29 +0000

Use a ConcurrentHashMap (JDK 1.5+) instead of the older Hashtable – should improve concurrency performance a lot.

By: Patrick Wolf

Patrick Wolf — Sun, 09 Sep 2007 10:42:42 +0000

Jeroen,

if you add the Apache module mod_gzip to your web-server config, you can even shrink it more. Have a look at http://dean.edwards.name/weblog/2007/08/js-compression/
John Scott has written a white paper about configuring mod_gzip at http://jes.blogs.shellprompt.net/2007/05/18/apex-delivering-pages-in-3-seconds-or-less/ (search for mod_gzip in the white paper).
Another performance boost is to check that your server sends in the header of the response that the file is cacheable, otherwise your browser will request again it with each page or new session.

Patrick