What javascript min tool does jquery use?

I have a great deal of javascript开发者_运维技巧 that needs to be min'd before being served to the end user. Currently, I'm using JSMIN, but I'd like to switch to something a bit more powerful (such as something with local variable replacement). I'm currently looking at YUI min developed by yahoo, and it got me thinking about the min tool that jquery uses. Does anyone know what it is and if it's publicly available? Also, any recommendations on other min tools that might be better suited than YUI min? If possible, I'd like a java solution so I can just plug the library into what I've already created for the JSMIN solution.

Thanks

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In jQuery 1.4, Google Closure Compiler is used.

See the FAQ in jQuery.

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Since this question was asked/answered, jQuery has switched over to an entirely JavaScript-based build system. Their minification is done using UglifyJS now, which runs in NodeJS.

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Here's a nice one that will do CSS as well.

http://jawr.java.net/

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If you look at the build folder in the trunk you can see they've been using YUI since Jan. 09