Bukkit

What steps will reproduce the problem?
1. The jar file will not load.
2.
3.

What is the expected output? What do you see instead?

What version of the product are you using?

Do you have an error log of what happened?

12:44:01 [SEVERE] Could not load 'plugins\lockout.jar' in folder 'plugins'
org.bukkit.plugin.InvalidPluginException: java.lang.NoClassDefFoundError: org/bu
kkit/event/block/BlockListener
        at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.j
ava:182)
        at org.bukkit.plugin.SimplePluginManager.loadPlugin(SimplePluginManager.
java:305)
        at org.bukkit.plugin.SimplePluginManager.loadPlugins(SimplePluginManager
.java:230)
        at org.bukkit.craftbukkit.v1_6_R3.CraftServer.loadPlugins(CraftServer.ja
va:241)
        at org.bukkit.craftbukkit.v1_6_R3.CraftServer.<init>(CraftServer.java:21
9)
        at net.minecraft.server.v1_6_R3.PlayerList.<init>(PlayerList.java:56)
        at net.minecraft.server.v1_6_R3.DedicatedPlayerList.<init>(SourceFile:11
)
        at net.minecraft.server.v1_6_R3.DedicatedServer.init(DedicatedServer.jav
a:107)
        at net.minecraft.server.v1_6_R3.MinecraftServer.run(MinecraftServer.java
:393)
        at net.minecraft.server.v1_6_R3.ThreadServerApplication.run(SourceFile:5
83)
Caused by: java.lang.NoClassDefFoundError: org/bukkit/event/block/BlockListener
        at java.lang.ClassLoader.defineClass1(Native Method)
        at java.lang.ClassLoader.defineClass(Unknown Source)
        at java.security.SecureClassLoader.defineClass(Unknown Source)
        at java.net.URLClassLoader.defineClass(Unknown Source)
        at java.net.URLClassLoader.access$100(Unknown Source)
        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.findClass0(PluginClassLoader
.java:80)
        at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.
java:53)
        at java.lang.ClassLoader.loadClass(Unknown Source)
        at java.lang.ClassLoader.loadClass(Unknown Source)
        at me.kokykikokolbywg.lockout.lockout.<init>(lockout.java:14)
        at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)

        at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)

        at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Sou
rce)
        at java.lang.reflect.Constructor.newInstance(Unknown Source)
        at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.j
ava:178)
        ... 9 more
Caused by: java.lang.ClassNotFoundException: org.bukkit.event.block.BlockListene
r
        at org.bukkit.plugin.java.PluginClassLoader.findClass0(PluginClassLoader
.java:70)
        at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.
java:53)
        at java.lang.ClassLoader.loadClass(Unknown Source)
        at java.lang.ClassLoader.loadClass(Unknown Source)
        ... 28 more

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