Saturday, February 26, 2011

Getting Groovy with Jar Versions

Oh how I love the Groovy!

I just needed to check version numbers of jar files in multiple folders and collate a table like:

While most jar files have the version number in either the Bundle-Version or Implementation-Version attributes of the MANIFEST.MF file, some do not follow this convention, and we need to either look for a file ending in _VERSION, or parse a pom.xml within a META-INF subfolder to get the version number.

Groovy makes it so easy to do this stuff. On top of this, creating the HTML table is a breeze. The icing on the cake is to save the file and open in Firefox in a couple of lines.



This would have taken hundreds of lines in Java. Groovy makes it concise, while allowing access to all Java libraries, resulting in code that is readable (if a little alien at first) to a Java developer.