What causes a ClassnNotFoundException to be thrown when loading a mod file?

[QuantumLeaf7895]

Hi all,

 

I've been working on updating my mod to 1.3.2, but I've noticed something -- when running my mod in eclipse it works fine; bur after reobfuscation and placing it in .minecraft's mods folder, minecraft refuses to boot, with an error message complaining about a "ClassNotFoundException:quantumaddon.QuantumAddonV3"  What causes it?

 

The error log looks like this:

 

--- BEGIN ERROR REPORT 85f9acd8 --------

Generated 9/22/12 9:07 PM

 

- Minecraft Version: 1.3.2

- Operating System: Mac OS X (i386) version 10.6.8

- Java Version: 1.6.0_35, Apple Inc.

- Java VM Version: Java HotSpot Client VM (mixed mode), Apple Inc.

- Memory: 490394224 bytes (467 MB) / 535232512 bytes (510 MB) up to 1070399488 bytes (1020 MB)

- JVM Flags: 3 total; -Xbootclasspath/a:/System/Library/PrivateFrameworks/JavaApplicationLauncher.framework/Resources/LauncherSupport.jar -Xms512M -Xmx1024M

- FML: FML v3.0.196.366 Minecraft Forge 4.1.1.251 4 mods loaded, 4 mods active

FML [Forge Mod Loader] (coremods) Unloaded->Constructed

Forge [Minecraft Forge] (coremods) Unloaded->Constructed

IC2 [industrialCraft 2] (industrialcraft-2_1.106.jar) Unloaded->Constructed

QuantumAddonV3 [QuantumAddonV3] (quantumaddon) Unloaded->Errored

- LWJGL: 2.4.2

- OpenGL: NVIDIA GeForce 320M OpenGL Engine GL version 2.1 NVIDIA-1.6.36, NVIDIA Corporation

- Is Modded: Definitely; 'forge,fml'

- Type: Client

- Texture Pack: Default

- Profiler Position: N/A (disabled)

 

cpw.mods.fml.common.LoaderException: java.lang.ClassNotFoundException: quantumaddon.QuantumAddonV3

at cpw.mods.fml.common.LoadController.transition(LoadController.java:102)

at cpw.mods.fml.common.Loader.loadMods(Loader.java:459)

at cpw.mods.fml.client.FMLClientHandler.beginMinecraftLoading(FMLClientHandler.java:144)

at net.minecraft.client.Minecraft.a(Minecraft.java:405)

at net.minecraft.client.Minecraft.run(Minecraft.java:737)

at java.lang.Thread.run(Thread.java:680)

Caused by: java.lang.ClassNotFoundException: quantumaddon.QuantumAddonV3

at cpw.mods.fml.relauncher.RelaunchClassLoader.findClass(RelaunchClassLoader.java:125)

at java.lang.ClassLoader.loadClass(ClassLoader.java:306)

at java.lang.ClassLoader.loadClass(ClassLoader.java:247)

at cpw.mods.fml.common.ModClassLoader.loadClass(ModClassLoader.java:57)

at java.lang.Class.forName0(Native Method)

at java.lang.Class.forName(Class.java:247)

at cpw.mods.fml.common.FMLModContainer.constructMod(FMLModContainer.java:341)

at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)

at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)

at java.lang.reflect.Method.invoke(Method.java:597)

at com.google.common.eventbus.EventHandler.handleEvent(EventHandler.java:69)

at com.google.common.eventbus.SynchronizedEventHandler.handleEvent(SynchronizedEventHandler.java:45)

at com.google.common.eventbus.EventBus.dispatch(EventBus.java:317)

at com.google.common.eventbus.EventBus.dispatchQueuedEvents(EventBus.java:300)

at com.google.common.eventbus.EventBus.post(EventBus.java:268)

at cpw.mods.fml.common.LoadController.propogateStateMessage(LoadController.java:124)

at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)

at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)

at java.lang.reflect.Method.invoke(Method.java:597)

at com.google.common.eventbus.EventHandler.handleEvent(EventHandler.java:69)

at com.google.common.eventbus.SynchronizedEventHandler.handleEvent(SynchronizedEventHandler.java:45)

at com.google.common.eventbus.EventBus.dispatch(EventBus.java:317)

at com.google.common.eventbus.EventBus.dispatchQueuedEvents(EventBus.java:300)

at com.google.common.eventbus.EventBus.post(EventBus.java:268)

at cpw.mods.fml.common.LoadController.distributeStateMessage(LoadController.java:81)

at cpw.mods.fml.common.Loader.loadMods(Loader.java:458)

... 4 more

Caused by: java.lang.NullPointerException

at org.objectweb.asm.ClassReader.<init>(Unknown Source)

at cpw.mods.fml.common.asm.transformers.SideTransformer.transform(SideTransformer.java:27)

at cpw.mods.fml.relauncher.RelaunchClassLoader.runTransformers(RelaunchClassLoader.java:167)

at cpw.mods.fml.relauncher.RelaunchClassLoader.findClass(RelaunchClassLoader.java:118)

... 31 more

--- END ERROR REPORT c017175d ----------

 

 

 

 

 

In MCP, I've created a folder called 'quantumaddon' inside the Common folder, and placed all of my mod classes there -- even the client proxy.  The start of QuantumAddonV3 looks like this:

 

 

 

package quantumaddon;

/*imports snipped*/

@Mod(modid = "QuantumAddonV3", name = "QuantumAddonV3", version = "3")

@NetworkMod(clientSideRequired = true, serverSideRequired = false)

public class QuantumAddonV3

{

@SidedProxy(clientSide = "quantumaddon.ClientProxy", serverSide = "quantumaddon.CommonProxy")

/* variable initialization snipped*/

 

@PreInit

public void preInit(FMLPreInitializationEvent event) {

 

/*standard configuration file stuff, nothing too exciting*/

}

@Init

public void load(FMLInitializationEvent event){

/*everything else snipped*/

 

 

And I checked, the file QuantumAddonV3.class is inside the quantumaddon folder in the mods folder in the .minecraft folder.  I'm using forge 4.1.1 build 251, and minecraft will run with other mods installed -- just not mine.  And if it's important -- I'm running a mac.