NOTE: Found a workaround, I just want to know where the problem is.
I am attempting to run a java *.jar file that runs on my debian setup but cannot get to run on a fresh install of Ubuntu with openjdk-7.
Setup Ubuntu 15.10, fresh 64-bit installed default-jdk downloaded XMage.jar from xmage.de.
Using the terminal -verbose option I notice that it freezes at the following line:
[loading sun.awt.X11.XKeysym$Keysym2JavaKeycode from /usr/lib/jvm/java-7-openjdk-amd64/jre/lib/rt.jar]
After 5 minutes I killed it. I then removed default-jdk and installed Oracle Java, which was able to run the jar file.
I am unsure if the issue lies with me, the version of Java, or the jar file. Any ideas on how I can find out more information? Never debugged java before.