[1.9] Exported mod works in Minecraft, but not in Eclipse

[JimiIT92]

I have a mod that will check if another mod is loaded in the game. So i've put this mod into the "run" folder of the project and launched the game. The mod is recognized as loaded, but for some reason the game crash, giving me this error related to that other mod (the mod i want to check is loaded)

[13:21:22] [Client thread/ERROR] [FML]: The following problems were captured during this phase
[13:21:22] [Client thread/ERROR] [FML]: Caught exception from mw
java.lang.NoClassDefFoundError: com/mineworld/blocks/plants/BlockSaplingMW
at com.mineworld.MW.preInit(MW.java:34) ~[MW.class:?]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_74]
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_74]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_74]
at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_74]
at net.minecraftforge.fml.common.FMLModContainer.handleModStateEvent(FMLModContainer.java:561) ~[forgeSrc-1.9-12.16.1.1887.jar:?]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_74]
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_74]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_74]
at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_74]
at com.google.common.eventbus.EventSubscriber.handleEvent(EventSubscriber.java:74) ~[guava-17.0.jar:?]
at com.google.common.eventbus.SynchronizedEventSubscriber.handleEvent(SynchronizedEventSubscriber.java:47) ~[guava-17.0.jar:?]
at com.google.common.eventbus.EventBus.dispatch(EventBus.java:322) ~[guava-17.0.jar:?]
at com.google.common.eventbus.EventBus.dispatchQueuedEvents(EventBus.java:304) ~[guava-17.0.jar:?]
at com.google.common.eventbus.EventBus.post(EventBus.java:275) ~[guava-17.0.jar:?]
at net.minecraftforge.fml.common.LoadController.sendEventToModContainer(LoadController.java:228) ~[forgeSrc-1.9-12.16.1.1887.jar:?]
at net.minecraftforge.fml.common.LoadController.propogateStateMessage(LoadController.java:206) ~[forgeSrc-1.9-12.16.1.1887.jar:?]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_74]
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_74]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_74]
at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_74]
at com.google.common.eventbus.EventSubscriber.handleEvent(EventSubscriber.java:74) ~[guava-17.0.jar:?]
at com.google.common.eventbus.SynchronizedEventSubscriber.handleEvent(SynchronizedEventSubscriber.java:47) ~[guava-17.0.jar:?]
at com.google.common.eventbus.EventBus.dispatch(EventBus.java:322) ~[guava-17.0.jar:?]
at com.google.common.eventbus.EventBus.dispatchQueuedEvents(EventBus.java:304) ~[guava-17.0.jar:?]
at com.google.common.eventbus.EventBus.post(EventBus.java:275) ~[guava-17.0.jar:?]
at net.minecraftforge.fml.common.LoadController.distributeStateMessage(LoadController.java:135) [LoadController.class:?]
at net.minecraftforge.fml.common.Loader.preinitializeMods(Loader.java:584) [Loader.class:?]
at net.minecraftforge.fml.client.FMLClientHandler.beginMinecraftLoading(FMLClientHandler.java:249) [FMLClientHandler.class:?]
at net.minecraft.client.Minecraft.startGame(Minecraft.java:472) [Minecraft.class:?]
at net.minecraft.client.Minecraft.run(Minecraft.java:381) [Minecraft.class:?]
at net.minecraft.client.main.Main.main(Main.java:118) [Main.class:?]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_74]
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_74]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_74]
at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_74]
at net.minecraft.launchwrapper.Launch.launch(Launch.java:135) [launchwrapper-1.12.jar:?]
at net.minecraft.launchwrapper.Launch.main(Launch.java:28) [launchwrapper-1.12.jar:?]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_74]
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_74]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_74]
at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_74]
at net.minecraftforge.gradle.GradleStartCommon.launch(GradleStartCommon.java:97) [start/:?]
at GradleStart.main(GradleStart.java:26) [start/:?]
Caused by: java.lang.ClassNotFoundException: com.mineworld.blocks.plants.BlockSaplingMW
at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:191) ~[launchwrapper-1.12.jar:?]
at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_74]
at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_74]
... 44 more
Caused by: java.lang.RuntimeException: java.lang.ClassNotFoundException: com.mineworld.world.gen.feature.WorldGenChristmasTree
at org.objectweb.asm.ClassWriter.getCommonSuperClass(ClassWriter.java:1684) ~[asm-debug-all-5.0.3.jar:5.0.3]
at org.objectweb.asm.ClassWriter.getMergedType(ClassWriter.java:1654) ~[asm-debug-all-5.0.3.jar:5.0.3]
at org.objectweb.asm.Frame.merge(Frame.java:1426) ~[asm-debug-all-5.0.3.jar:5.0.3]
at org.objectweb.asm.Frame.merge(Frame.java:1325) ~[asm-debug-all-5.0.3.jar:5.0.3]
at org.objectweb.asm.MethodWriter.visitMaxs(MethodWriter.java:1475) ~[asm-debug-all-5.0.3.jar:5.0.3]
at org.objectweb.asm.commons.LocalVariablesSorter.visitMaxs(LocalVariablesSorter.java:170) ~[asm-debug-all-5.0.3.jar:5.0.3]
at org.objectweb.asm.ClassReader.readCode(ClassReader.java:1554) ~[asm-debug-all-5.0.3.jar:5.0.3]
at org.objectweb.asm.ClassReader.readMethod(ClassReader.java:1017) ~[asm-debug-all-5.0.3.jar:5.0.3]
at org.objectweb.asm.ClassReader.accept(ClassReader.java:693) ~[asm-debug-all-5.0.3.jar:5.0.3]
at org.objectweb.asm.ClassReader.accept(ClassReader.java:506) ~[asm-debug-all-5.0.3.jar:5.0.3]
at net.minecraftforge.fml.common.asm.transformers.DeobfuscationTransformer.transform(DeobfuscationTransformer.java:44) ~[forgeSrc-1.9-12.16.1.1887.jar:?]
at net.minecraft.launchwrapper.LaunchClassLoader.runTransformers(LaunchClassLoader.java:279) ~[launchwrapper-1.12.jar:?]
at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:176) ~[launchwrapper-1.12.jar:?]
at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_74]
at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_74]
... 44 more

 

I've tried loading this mod in Minecraft and everything works fine, this error only occurs if i try to load it from eclipse? Any idea of what's causing this?

[Guest]

If you want to use the mod as a library, I would suggest putting the mod into a folder called libs which you should create in your project's main folder. Then you need to add the mod as a library in eclipse. Also, if possible, you should get the deobfuscated (often called dev) version of the mod.

[JimiIT92]

Adding the mod as library has solved the issue, thanks for your help