Error

[19:50:43 ERROR]: Error occurred while enabling Alpha v0.5 (Is it up to date?)
java.lang.IllegalArgumentException: Plugin already initialized!
        at org.bukkit.plugin.java.PluginClassLoader.initialize(PluginClassLoader.java:122) ~[spigot-1.7.10.jar:git-Spigot-1.7.9-R0.2-208-ge0f2e95]
        at org.bukkit.plugin.java.JavaPlugin.<init>(JavaPlugin.java:66) ~[spigot-1.7.10.jar:git-Spigot-1.7.9-R0.2-208-ge0f2e95]
        at com.chaoticmc.alpha.UserInterface.GUI.<init>(GUI.java:20) ~[?:?]
        at com.chaoticmc.alpha.AlphaPlugin.onEnable(AlphaPlugin.java:25) ~[?:?]
        at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:316) ~[spigot-1.7.10.jar:git-Spigot-1.7.9-R0.2-208-ge0f2e95]
        at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:332) [spigot-1.7.10.jar:git-Spigot-1.7.9-R0.2-208-ge0f2e95]
        at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:412) [spigot-1.7.10.jar:git-Spigot-1.7.9-R0.2-208-ge0f2e95]
        at org.bukkit.craftbukkit.v1_7_R4.CraftServer.loadPlugin(CraftServer.java:476) [spigot-1.7.10.jar:git-Spigot-1.7.9-R0.2-208-ge0f2e95]
        at org.bukkit.craftbukkit.v1_7_R4.CraftServer.enablePlugins(CraftServer.java:394) [spigot-1.7.10.jar:git-Spigot-1.7.9-R0.2-208-ge0f2e95]
        at net.minecraft.server.v1_7_R4.MinecraftServer.n(MinecraftServer.java:360) [spigot-1.7.10.jar:git-Spigot-1.7.9-R0.2-208-ge0f2e95]
        at net.minecraft.server.v1_7_R4.MinecraftServer.g(MinecraftServer.java:334) [spigot-1.7.10.jar:git-Spigot-1.7.9-R0.2-208-ge0f2e95]
        at net.minecraft.server.v1_7_R4.MinecraftServer.a(MinecraftServer.java:290) [spigot-1.7.10.jar:git-Spigot-1.7.9-R0.2-208-ge0f2e95]
        at net.minecraft.server.v1_7_R4.DedicatedServer.init(DedicatedServer.java:210) [spigot-1.7.10.jar:git-Spigot-1.7.9-R0.2-208-ge0f2e95]
        at net.minecraft.server.v1_7_R4.MinecraftServer.run(MinecraftServer.java:458) [spigot-1.7.10.jar:git-Spigot-1.7.9-R0.2-208-ge0f2e95]
        at net.minecraft.server.v1_7_R4.ThreadServerApplication.run(SourceFile:628) [spigot-1.7.10.jar:git-Spigot-1.7.9-R0.2-208-ge0f2e95]
Caused by: java.lang.IllegalStateException: Initial initialization
        at org.bukkit.plugin.java.PluginClassLoader.initialize(PluginClassLoader.java:125) ~[spigot-1.7.10.jar:git-Spigot-1.7.9-R0.2-208-ge0f2e95]
        at org.bukkit.plugin.java.JavaPlugin.<init>(JavaPlugin.java:66) ~[spigot-1.7.10.jar:git-Spigot-1.7.9-R0.2-208-ge0f2e95]
        at com.chaoticmc.alpha.AlphaPlugin.<init>(AlphaPlugin.java:12) ~[?:?]
        at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[?:1.8.0_144]
        at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source) ~[?:1.8.0_144]
        at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source) ~[?:1.8.0_144]
        at java.lang.reflect.Constructor.newInstance(Unknown Source) ~[?:1.8.0_144]
        at java.lang.Class.newInstance(Unknown Source) ~[?:1.8.0_144]
        at org.bukkit.plugin.java.PluginClassLoader.<init>(PluginClassLoader.java:76) ~[spigot-1.7.10.jar:git-Spigot-1.7.9-R0.2-208-ge0f2e95]
        at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:129) ~[spigot-1.7.10.jar:git-Spigot-1.7.9-R0.2-208-ge0f2e95]
        at org.bukkit.plugin.SimplePluginManager.loadPlugin(SimplePluginManager.java:336) ~[spigot-1.7.10.jar:git-Spigot-1.7.9-R0.2-208-ge0f2e95]
        at org.bukkit.plugin.SimplePluginManager.loadPlugins(SimplePluginManager.java:258) ~[spigot-1.7.10.jar:git-Spigot-1.7.9-R0.2-208-ge0f2e95]
        at org.bukkit.craftbukkit.v1_7_R4.CraftServer.loadPlugins(CraftServer.java:369) ~[spigot-1.7.10.jar:git-Spigot-1.7.9-R0.2-208-ge0f2e95]
        at net.minecraft.server.v1_7_R4.DedicatedServer.init(DedicatedServer.java:152) ~[spigot-1.7.10.jar:git-Spigot-1.7.9-R0.2-208-ge0f2e95]
        ... 2 more