[11:13:56 ERROR]: Could not load 'plugins\OnlineList.jar' in folder 'plugins'
org.bukkit.plugin.InvalidPluginException: java.lang.UnsupportedClassVersionError
: onlinelist/Main : Unsupported major.minor version 52.0
        at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.j
ava:133) ~[spigot.jar:git-Spigot-1649]
        at org.bukkit.plugin.SimplePluginManager.loadPlugin(SimplePluginManager.
java:341) ~[spigot.jar:git-Spigot-1649]
        at org.bukkit.plugin.SimplePluginManager.loadPlugins(SimplePluginManager
.java:263) [spigot.jar:git-Spigot-1649]
        at org.bukkit.craftbukkit.v1_7_R4.CraftServer.loadPlugins(CraftServer.ja
va:369) [spigot.jar:git-Spigot-1649]
        at net.minecraft.server.v1_7_R4.DedicatedServer.init(DedicatedServer.jav
a:152) [spigot.jar:git-Spigot-1649]
        at net.minecraft.server.v1_7_R4.MinecraftServer.run(MinecraftServer.java
:458) [spigot.jar:git-Spigot-1649]
        at net.minecraft.server.v1_7_R4.ThreadServerApplication.run(SourceFile:6
28) [spigot.jar:git-Spigot-1649]
Caused by: java.lang.UnsupportedClassVersionError: onlinelist/Main : Unsupported
 major.minor version 52.0
        at java.lang.ClassLoader.defineClass1(Native Method) ~[?:1.7.0_67]
        at java.lang.ClassLoader.defineClass(Unknown Source) ~[?:1.7.0_67]
        at java.security.SecureClassLoader.defineClass(Unknown Source) ~[?:1.7.0
_67]
        at java.net.URLClassLoader.defineClass(Unknown Source) ~[?:1.7.0_67]
        at java.net.URLClassLoader.access$100(Unknown Source) ~[?:1.7.0_67]
        at java.net.URLClassLoader$1.run(Unknown Source) ~[?:1.7.0_67]
        at java.net.URLClassLoader$1.run(Unknown Source) ~[?:1.7.0_67]
        at java.security.AccessController.doPrivileged(Native Method) ~[?:1.7.0_
67]
        at java.net.URLClassLoader.findClass(Unknown Source) ~[?:1.7.0_67]
        at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.
java:101) ~[spigot.jar:git-Spigot-1649]
        at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.
java:86) ~[spigot.jar:git-Spigot-1649]
        at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.7.0_67]
        at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.7.0_67]
        at java.lang.Class.forName0(Native Method) ~[?:1.7.0_67]
        at java.lang.Class.forName(Unknown Source) ~[?:1.7.0_67]
        at org.bukkit.plugin.java.PluginClassLoader.<init>(PluginClassLoader.jav
a:64) ~[spigot.jar:git-Spigot-1649]
        at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.j
ava:129) ~[spigot.jar:git-Spigot-1649]
        ... 6 more