Looks like Eclipse has its own loader:
Rsrc-Main-Class: my.Main
Main-Class: org.eclipse.jdt.internal.jarinjarloader.JarRsrcLoader
After some trying, the OneJar plugin got me most of the way there… unfortunately not the whole way:
[Boot] INFO: setProperties(com.simontuffs.onejar.JarClassLoader@6e0be858)
[Boot] INFO: using JarClassLoader: com.simontuffs.onejar.JarClassLoader
Exception in thread "main" java.lang.NullPointerException
at java.lang.String.replace(String.java:2240)
at com.simontuffs.onejar.JarClassLoader.replaceProps(JarClassLoader.java:501)
at com.simontuffs.onejar.JarClassLoader.load(JarClassLoader.java:349)
at com.simontuffs.onejar.JarClassLoader.load(JarClassLoader.java:319)
at com.simontuffs.onejar.Boot.run(Boot.java:295)
at com.simontuffs.onejar.Boot.main(Boot.java:161)
I’ll try a few more things and open an issue on the OneJar repo if I think it’s their issue. Thanks for your help!