Mods

Hello, I am looking for guidance on the best approach to creating a party system I already have the backbone and a system working with commands but I am looking to attach this to a ui(just finished making) so I am looking for advice on the best way to do this going forward, I assume packets will play a big part in the communication to so I can get access to EntityPlayerMP as I believe for the client its EntityClientPlayerMP, So I have a couple of functions that handle it all :  createParty(EntityPlayerMP player); joinParty(EntityPlayerMP player, int inviteIdentifier); inviteParty(EntityPlayerMP sender, EntityPlayerMP invitedPlayer);   Will I need to create different packets and messages for each of these ? if so my idea for the inviteParty is to send over the invitedPlayer uuid but how do I then receive the the player from the current Minecraft server?   Any information will be appreciated.   Regards, Discult

I had to reinstall my IDE because it got hung up, but now when I try to run client / server I get an error message: I had this error before the reason was the lib version of the project, because Java 15 removed the NashornScriptEngineFactory, I think, but the library of my project is version 1.8, I have already reimported the project, changed the java version but I get always the same error. Exception in thread "main" [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: java.lang.NoClassDefFoundError: jdk/nashorn/api/scripting/NashornScriptEngineFactory [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at net.minecraftforge.coremod.CoreModEngine.loadCoreMod(CoreModEngine.java:48) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at net.minecraftforge.coremod.CoreModProvider.addCoreMod(CoreModProvider.java:12) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.accept(ForEachOps.java:183) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at java.base/java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1625) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at java.base/java.util.stream.ReferencePipeline$Head.forEach(ReferencePipeline.java:658) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at java.base/java.util.stream.ReferencePipeline$7$1.accept(ReferencePipeline.java:274) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:195) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:195) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at java.base/java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1625) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:484) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:474) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at java.base/java.util.stream.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:150) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:173) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at java.base/java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:497) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at net.minecraftforge.fml.loading.LoadingModList.addCoreMods(LoadingModList.java:85) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at net.minecraftforge.fml.loading.moddiscovery.ModDiscoverer.discoverMods(ModDiscoverer.java:129) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at net.minecraftforge.fml.loading.FMLLoader.beginModScan(FMLLoader.java:215) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at net.minecraftforge.fml.loading.FMLServiceProvider.runScan(FMLServiceProvider.java:107) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at cpw.mods.modlauncher.TransformationServiceDecorator.runScan(TransformationServiceDecorator.java:114) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at cpw.mods.modlauncher.TransformationServicesHandler.lambda$runScanningTransformationServices$8(TransformationServicesHandler.java:115) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at java.base/java.util.stream.ReferencePipeline$7$1.accept(ReferencePipeline.java:271) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at java.base/java.util.HashMap$ValueSpliterator.forEachRemaining(HashMap.java:1766) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:484) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:474) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at java.base/java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:913) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at java.base/java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:578) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at cpw.mods.modlauncher.TransformationServicesHandler.runScanningTransformationServices(TransformationServicesHandler.java:116) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at cpw.mods.modlauncher.TransformationServicesHandler.initializeTransformationServices(TransformationServicesHandler.java:63) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at cpw.mods.modlauncher.Launcher.run(Launcher.java:76) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at cpw.mods.modlauncher.Launcher.main(Launcher.java:66) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1048]: at net.minecraftforge.userdev.LaunchTesting.main(LaunchTesting.java:105) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1057]: Caused by: java.lang.ClassNotFoundException: jdk.nashorn.api.scripting.NashornScriptEngineFactory [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1057]: at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:606) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1057]: at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:168) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1057]: at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:522) [11:45:41] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1057]: ... 33 more  

why

This makes no sense.

Ah, so replacing anything inside the mods.toml would not be useful at all?