lol yeah just read it again an your totally right its a different error , sorry 
^ I created a ticket for the different error 
(https://hub.spigotmc.org/jira/browse/BUILDTOOLS-21)
It's not helpful if you don't provide the error.
Haven't been able to try and reproduce as I now get a different error ;(
Robin, I'm afraid that sounds like a different bug 
This is why we have a wiki, you need to update BuildTools.
http://spigotmc.org/wiki/buildtools
Hi I just encountered a similar problem, it looks like jacobe is not in the builddata repo any more, so it complains about that, later on it crashes because the nms-patches cant be applied to a non formatted .java file.
The second time it skips that and then the build fails.
I fixed it by downloading jacobe manually and putting it in the BuildData folder, after git pulled for updates
Sorry haven't had time to test this and the other ticket, don't worry though I will do it at some point soon 
Any update on the status of this ticket?
Please do, I will keep the ticket open until then.
I'll try and reproduce it and if I do, will do that.
No log, either screenshot it, or...
Right click top left corner > properties > enable QuickEdit mode > left drag to select, right click copies
Do you know where they're kept (if they're saved) because I stupidly didn't copy or screenshot the error But I am pretty sure it WAS mvn clean...
mvn clean won't cause an issue the first time, we would need an error log from your first run to further verify what the issue is.