Launch an OSGi app and automatically kill its running instance
If you use Eclipse to develop OSGi based applications you may use the OSGi Launcher provided by the PDE Tooling. It’s cool tooling because it gives you full control over the OSGi instance to be launched. You can choose the OSGi framework (e.g. Equinox or Felix), select the bundles to install and much more.
But this launcher has one drawback that hurts every time I run across it. It appears when an OSGi application uses the OSGi HttpService. When you used this service you may have configured a port for it via the property “org.osgi.service.http.port” VM Argument. I use this configuration all the time.
When I launch the application everything works fine the first time. But, during development I often come to the point where I need to relaunch the application. When I forget to kill the previous running instance I get a java.net.BindException because the address is already in use. So, to fix this I have to kill both instances and launch it again. This happens to me a lot just because I forget to terminate the previous instance. Of course this isn’t a bug because it’s often useful to launch a second instance of the same configuration. But, not when it comes to developing with the HttpService.
There is a fix now (though not necessarily for my forgetfulness ;)). Luckily we live in a modular world in Eclipse. As a result, I was able to develop a separate bundle called the “OSGi Eliminator” (what a descriptive name :)). The bundle contributes the functionality to automatically terminate a running OSGi Instance when you try to launch the same instance a second time. This functionality already existed in the RAP launcher created by Rüdiger Hermann. All I did was to refactor the functionality out to make it run in a separate bundle and contribute to the OSGi Launcher instead of the RAP Launcher. This solves an annoying problem for me – maybe for you as well?
You can find this bundle on GitHub. I also created a p2 repository that lets you install the OSGi Eliminator directly into Eclipse.
- p2 repository: http://hstaudacher.github.com/OSGi-launcher-enhancements/
- git repository on GitHub: https://github.com/hstaudacher/OSGi-launcher-enhancements