Some weird error

Eh, I started getting this error randomly. Not sure how to fix it.. Maybe you do?
Error:

Code:java

15:58:56 [SEVERE] Error occurred while enabling Skillz vjenkins-Skillz-203 (Is i
t up to date?)
java.lang.NoClassDefFoundError: nl/lolmen/Skillz/Skillz$4
        at nl.lolmen.Skillz.Skillz.startUserSavingThread(Skillz.java:526)
        at nl.lolmen.Skillz.Skillz.onEnable(Skillz.java:105)
        at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:215)
        at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader
.java:336)
        at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManage
r.java:381)
        at org.bukkit.craftbukkit.CraftServer.loadPlugin(CraftServer.java:250)
        at org.bukkit.craftbukkit.CraftServer.enablePlugins(CraftServer.java:232
)
        at net.minecraft.server.MinecraftServer.t(MinecraftServer.java:371)
        at net.minecraft.server.MinecraftServer.a(MinecraftServer.java:358)
        at net.minecraft.server.MinecraftServer.init(MinecraftServer.java:187)
        at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:422)
        at net.minecraft.server.ThreadServerApplication.run(SourceFile:492)
Caused by: java.lang.ClassNotFoundException: nl.lolmen.Skillz.Skillz$4
        at java.net.URLClassLoader$1.run(Unknown Source)
        at java.net.URLClassLoader$1.run(Unknown Source)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(Unknown Source)
        at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.
java:41)
        at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.
java:29)
        at java.lang.ClassLoader.loadClass(Unknown Source)
        at java.lang.ClassLoader.loadClass(Unknown Source)
        ... 12 more

And my code:

Code:java

@Override
    public void onEnable() {
        double time = System.nanoTime();
        this.makeSettings();
        this.loadUserManager();
        this.startUserSavingThread();
        ...

Code:java

private void startUserSavingThread() {
        this.getServer().getScheduler().scheduleAsyncRepeatingTask(this, new Runnable(){
            @Override
            public void run() {
                getLogger().info("Saving Skillz Users..");
                getUserManager().save(true);
            }
        }, 24000L, 24000L);
    }

The really weird thing is that line 526 from the error isn't in the startUserSavingThread() Method. I'm guessing something got messed up.
I'm using Maven + Jenkins, and I'm pretty noobie with it. Maybe I configured something wrong in it?

 

NoClassDefinitionFound || ClassNotFoundException

Try surround the trouble areas with a try catch statement and it will tell you exactly where the error is occurring.

 

I don't see why this would work. I already have a stacktrace, no need to generate another one, right?

 

not exactly, unless your hiding the throwable somewhere i would try what i said above then look at it.

 

Well, seems I 'partially' fixed it. Instead of building it with Jenkins, I built it with Netbeans. It seems Jenkins just uses the wrong data to build my project (eh, don't know how to fix that :O)

 

well, glad you partially got it fixed. when errors pop up like that it tells you generally where it is. when you have the try catch it tells you exactly where the error occurs.

 

the no classfound error has been normal for me lately. To fix it i have been leftclicking once on my project and F5 to refresh. Some times ill "Clean" the project and that usually fixes the problems.

 

Yea that also seemed to work a bit. (Clean)