Running multiple launch configurations at once
I found this post on the Eclipse trackers: Start multiple debug configurations at once
While it talks about multi-launching debug configurations, I think it is just as applicable to run configurations.
You may want to right click a run configuration in group launch and configure it.
EDIT: According to this answer since Eclipse Oxygen (4.7.0) you can use a run configuration of the type Launch Group for that.
Just install "C/C++ Development Tools" from the CDT (see eclipse.org/cdt/downloads.php ) - this single package is enough, no other CDT packages are needed. This won't disturb your Java environment ;-) Then you have "Launch Groups", for any kind of project, including Java projects. See the following screenshot:
You can run or debug the projects (also mixed mode), define delay times and so on. Have fun!
Since Eclipse Oxygen (4.7.0) you can use a run configuration of the type Launch Group for that.
This short video shows how to use a Launch Group.