I'm writing here to give an update on my attempts to modify someone else's mod. After some thinking and searching, I decided the most feasible way to do this is to write my own mod that will be basically just a copy of the original mod, just with my little change. After a lot of struggles, including having to completely reinstall Eclipse, I managed to copy all the code from the original mod to my mod, plus some extra code from the Collective library, since I still don't know how to work with mod dependencies. Eventually, there were no more errors displayed in Eclipse, so I decided to launch the mod, and it first seemed to work, but then it gave me this error:
[mException in thread "main" [32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: java.lang.NoClassDefFoundError: jdk/nashorn/api/scripting/NashornScriptEngineFactory[mException in thread "main" [32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: java.lang.NoClassDefFoundError: jdk/nashorn/api/scripting/NashornScriptEngineFactory[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at net.minecraftforge.coremod.CoreModEngine.loadCoreMod(CoreModEngine.java:48)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at net.minecraftforge.coremod.CoreModProvider.addCoreMod(CoreModProvider.java:12)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.accept(ForEachOps.java:183)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1625)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.ReferencePipeline$Head.forEach(ReferencePipeline.java:762)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.ReferencePipeline$7$1.accept(ReferencePipeline.java:276)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1625)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:509)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:499)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:150)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:173)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:596)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at net.minecraftforge.fml.loading.LoadingModList.addCoreMods(LoadingModList.java:88)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at net.minecraftforge.fml.loading.moddiscovery.ModDiscoverer.discoverMods(ModDiscoverer.java:125)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at net.minecraftforge.fml.loading.FMLLoader.beginModScan(FMLLoader.java:213)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at net.minecraftforge.fml.loading.FMLServiceProvider.runScan(FMLServiceProvider.java:107)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at cpw.mods.modlauncher.TransformationServiceDecorator.runScan(TransformationServiceDecorator.java:111)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at cpw.mods.modlauncher.TransformationServicesHandler.lambda$runScanningTransformationServices$8(TransformationServicesHandler.java:115)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.ReferencePipeline$7$1.accept(ReferencePipeline.java:273)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.HashMap$ValueSpliterator.forEachRemaining(HashMap.java:1779)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:509)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:499)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:921)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:682)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at cpw.mods.modlauncher.TransformationServicesHandler.runScanningTransformationServices(TransformationServicesHandler.java:116)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at cpw.mods.modlauncher.TransformationServicesHandler.initializeTransformationServices(TransformationServicesHandler.java:63)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at cpw.mods.modlauncher.Launcher.run(Launcher.java:75)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at cpw.mods.modlauncher.Launcher.main(Launcher.java:65)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at net.minecraftforge.userdev.LaunchTesting.main(LaunchTesting.java:105)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1087]: Caused by: java.lang.ClassNotFoundException: jdk.nashorn.api.scripting.NashornScriptEngineFactory[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1087]: at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:641)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1087]: at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:188)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1087]: at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1087]: ... 33 more[m
Does anyone know what is the problem caused by? Thank you very much for any reply.
I tried downdating my Java JDK to version 8, as you say, but now my Eclipse doesn't work, it apparently requires version of Java 11 or higher. I tried downdating Eclipse as well, but I can't find any older version as a replacement. Is there any way around this?
I tried using the method described in the link you provided, but the key link it mentiones (http://download.eclipse.org/eclipse/updates/4.3-P-builds/) doesn't seem to work. I tried googling this problem, but all the relevant articles directed me to the same link. But still, thank you for your attempt. Any other suggestions?
EDIT: With help from Eclipse forum, I finally managed to get the experimental Minecraft in Eclipse running. The only thing it took was to change the settings in Preferences to run the project in Java 8. Thank you, TileEntity, for help!
Hello,
I'm writing here to give an update on my attempts to modify someone else's mod. After some thinking and searching, I decided the most feasible way to do this is to write my own mod that will be basically just a copy of the original mod, just with my little change. After a lot of struggles, including having to completely reinstall Eclipse, I managed to copy all the code from the original mod to my mod, plus some extra code from the Collective library, since I still don't know how to work with mod dependencies. Eventually, there were no more errors displayed in Eclipse, so I decided to launch the mod, and it first seemed to work, but then it gave me this error:
[mException in thread "main" [32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: java.lang.NoClassDefFoundError: jdk/nashorn/api/scripting/NashornScriptEngineFactory[mException in thread "main" [32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: java.lang.NoClassDefFoundError: jdk/nashorn/api/scripting/NashornScriptEngineFactory[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at net.minecraftforge.coremod.CoreModEngine.loadCoreMod(CoreModEngine.java:48)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at net.minecraftforge.coremod.CoreModProvider.addCoreMod(CoreModProvider.java:12)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.accept(ForEachOps.java:183)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1625)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.ReferencePipeline$Head.forEach(ReferencePipeline.java:762)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.ReferencePipeline$7$1.accept(ReferencePipeline.java:276)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1625)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:509)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:499)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:150)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:173)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:596)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at net.minecraftforge.fml.loading.LoadingModList.addCoreMods(LoadingModList.java:88)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at net.minecraftforge.fml.loading.moddiscovery.ModDiscoverer.discoverMods(ModDiscoverer.java:125)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at net.minecraftforge.fml.loading.FMLLoader.beginModScan(FMLLoader.java:213)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at net.minecraftforge.fml.loading.FMLServiceProvider.runScan(FMLServiceProvider.java:107)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at cpw.mods.modlauncher.TransformationServiceDecorator.runScan(TransformationServiceDecorator.java:111)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at cpw.mods.modlauncher.TransformationServicesHandler.lambda$runScanningTransformationServices$8(TransformationServicesHandler.java:115)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.ReferencePipeline$7$1.accept(ReferencePipeline.java:273)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.HashMap$ValueSpliterator.forEachRemaining(HashMap.java:1779)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:509)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:499)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:921)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at java.base/java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:682)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at cpw.mods.modlauncher.TransformationServicesHandler.runScanningTransformationServices(TransformationServicesHandler.java:116)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at cpw.mods.modlauncher.TransformationServicesHandler.initializeTransformationServices(TransformationServicesHandler.java:63)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at cpw.mods.modlauncher.Launcher.run(Launcher.java:75)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at cpw.mods.modlauncher.Launcher.main(Launcher.java:65)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1078]: at net.minecraftforge.userdev.LaunchTesting.main(LaunchTesting.java:105)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1087]: Caused by: java.lang.ClassNotFoundException: jdk.nashorn.api.scripting.NashornScriptEngineFactory[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1087]: at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:641)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1087]: at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:188)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1087]: at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)[m[32m[14:37:13] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1087]: ... 33 more[m
Does anyone know what is the problem caused by? Thank you very much for any reply.
It is an issue with the Java version you are using - make sure you are using the same Java version as the original mod
Thank you. And how can I find out what Java version was the original mod using?
Check the files of the original mod - maybe there are some information
Usually it is:
1.18 and newer: Java 17
1.17: Java 16
1.16 and older: Java 8
I tried downdating my Java JDK to version 8, as you say, but now my Eclipse doesn't work, it apparently requires version of Java 11 or higher. I tried downdating Eclipse as well, but I can't find any older version as a replacement. Is there any way around this?
Take a look at some guides - should be similar to another eclipse builds
https://blogs.eclipse.org/post/wayne-beaton/add-java-8-support-eclipse-kepler
I tried using the method described in the link you provided, but the key link it mentiones (http://download.eclipse.org/eclipse/updates/4.3-P-builds/) doesn't seem to work. I tried googling this problem, but all the relevant articles directed me to the same link. But still, thank you for your attempt. Any other suggestions?
EDIT: With help from Eclipse forum, I finally managed to get the experimental Minecraft in Eclipse running. The only thing it took was to change the settings in Preferences to run the project in Java 8. Thank you, TileEntity, for help!