I am running Ubuntu 18.04.
I installed the SpongeVanilla jar, moved it to a directory, and ran the jar file using terminal.
Results:
Here is my terminal output when I ran the jar file:
Downloading the versions manifest…
Downloading minecraft_server.1.12.2.jar… This can take a while.
https://launcher.mojang.com/v1/objects/886945bfb2b978778c3a0288fd7fab09d315b25f/server.jar
Successfully downloaded minecraft_server.1.12.2.jar and verified checksum!
Downloading launchwrapper-1.12.jar… This can take a while.
https://libraries.minecraft.net/net/minecraft/launchwrapper/1.12/launchwrapper-1.12.jar
Successfully downloaded launchwrapper-1.12.jar and verified checksum!
Exception in thread “main” java.lang.NoClassDefFoundError: net/minecraft/launchwrapper/Launch
at org.spongepowered.server.launch.VanillaServerMain.main(VanillaServerMain.java:126)
at org.spongepowered.server.launch.VersionCheckingMain.main(VersionCheckingMain.java:38)
Caused by: java.lang.ClassNotFoundException: net.minecraft.launchwrapper.Launch
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:581)
at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:522)
… 2 more
Thanks for your help!
EDIT Solved. See comment marked solution. This AskUbuntu post helped me switch to Java 8.