Today, I took the time to publish an old project of mine after there were some requests to do so. The project is a small and lightweight launcher framework to deploy and start Java SE applications in a cross-platform manner.
The JAR Hell is well known and I run into some issues, when I had to deploy small console applications (file converters mainly) on Linux, Windows and SunOS. My goal on this former project was to deploy some 3rd party libraries like loggers and so forth together with some own applications on different platforms. The whole project was quite complex and the main libraries were already available. To prevent a duplicated development, the idea was to reuse the JARs and to deploy them on the different OS. The question was how…
I definitely did not want to unpack all JARs to add Classpath entries to the MANIFEST.MF files. I also did not want to shade everything together to have an easy reuse of 3rd party and own libraries. Additionally, I also wanted to exchange own libraries on the fly without unpacking the former deployed libraries. So the basic concept KickStart was born.
KickStart is a small executable jar and a properties file. These two are copied somewhere into the filesystem of the OS. Additionally, some directories created and configured in the properties file. After that, all libraries are copied into the locations needed and everything is ready to run with a simple:
java -jar kickstart-1.0.0.jar MainClass parameter1 parameter2 ...
KickStarts looks into the directory for the 3rd party libraries and into the own libraries directory and binds everything together internally into one classloader. Afterwards, the given MainClass is looked up and the static main method is called with the provided parameters.
With this simple approach it is easy to have a collection of JARs which may contain multiple applications. A simple shell script hides the call to KickStart and can be added to the PATH environment variable.
With this approach, the redeployment of libraries is possible as long as the interfaces are stable. So during the development it is possible to exchange the libraries with newer, more optimized ones.
KickStart was published at PureSol Technologies Open Source Website at: http://opensource.puresol-technologies.com/kickstart