[16:51:53 INFO]: [SkyWars] Enabling SkyWars v1.0.0
[16:51:53 ERROR]: Error occurred while enabling SkyWars v1.0.0 (Is it up to date?)
java.lang.NoClassDefFoundError: net/minecraft/server/v1_11_R1/MinecraftServer
        at io.github.Leonardo0013YT.SkyWars.utils.Properties.setServerProperty(Properties.java:13) ~[?:?]
        at io.github.Leonardo0013YT.SkyWars.Main.onEnable(Main.java:103) ~[?:?]
        at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:264) ~[Paper-1.12.2-v1613.jar:git-Paper-1613]
        at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:316) ~[Paper-1.12.2-v1613.jar:git-Paper-1613]
        at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:405) ~[Paper-1.12.2-v1613.jar:git-Paper-1613]
        at org.bukkit.craftbukkit.v1_12_R1.CraftServer.enablePlugin(CraftServer.java:395) ~[Paper-1.12.2-v1613.jar:git-Paper-1613]
        at org.bukkit.craftbukkit.v1_12_R1.CraftServer.enablePlugins(CraftServer.java:344) ~[Paper-1.12.2-v1613.jar:git-Paper-1613]
        at net.minecraft.server.v1_12_R1.MinecraftServer.t(MinecraftServer.java:442) ~[Paper-1.12.2-v1613.jar:git-Paper-1613]
        at net.minecraft.server.v1_12_R1.MinecraftServer.l(MinecraftServer.java:403) ~[Paper-1.12.2-v1613.jar:git-Paper-1613]
        at net.minecraft.server.v1_12_R1.MinecraftServer.a(MinecraftServer.java:341) ~[Paper-1.12.2-v1613.jar:git-Paper-1613]
        at net.minecraft.server.v1_12_R1.DedicatedServer.init(DedicatedServer.java:289) ~[Paper-1.12.2-v1613.jar:git-Paper-1613]
        at net.minecraft.server.v1_12_R1.MinecraftServer.run(MinecraftServer.java:616) ~[Paper-1.12.2-v1613.jar:git-Paper-1613]
        at java.lang.Thread.run(Thread.java:748) [?:1.8.0_191]
Caused by: java.lang.ClassNotFoundException: net.minecraft.server.v1_11_R1.MinecraftServer
        at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:109) ~[Paper-1.12.2-v1613.jar:git-Paper-1613]
        at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:104) ~[Paper-1.12.2-v1613.jar:git-Paper-1613]
        at java.lang.ClassLoader.loadClass(ClassLoader.java:424) ~[?:1.8.0_191]
        at java.lang.ClassLoader.loadClass(ClassLoader.java:357) ~[?:1.8.0_191]
        ... 13 more
[16:51:53 INFO]: [SkyWars] Disabling SkyWars v1.0.0
[16:51:53 ERROR]: Error occurred while disabling SkyWars v1.0.0 (Is it up to date?)
java.lang.NoClassDefFoundError: net/minecraft/server/v1_11_R1/MinecraftServer
        at io.github.Leonardo0013YT.SkyWars.utils.Properties.savePropertiesFile(Properties.java:9) ~[?:?]
        at io.github.Leonardo0013YT.SkyWars.Main.onDisable(Main.java:194) ~[?:?]
        at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:266) ~[Paper-1.12.2-v1613.jar:git-Paper-1613]
        at org.bukkit.plugin.java.JavaPluginLoader.disablePlugin(JavaPluginLoader.java:350) ~[Paper-1.12.2-v1613.jar:git-Paper-1613]
        at org.bukkit.plugin.SimplePluginManager.disablePlugin(SimplePluginManager.java:437) ~[Paper-1.12.2-v1613.jar:git-Paper-1613]
        at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:320) ~[Paper-1.12.2-v1613.jar:git-Paper-1613]
        at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:405) ~[Paper-1.12.2-v1613.jar:git-Paper-1613]
        at org.bukkit.craftbukkit.v1_12_R1.CraftServer.enablePlugin(CraftServer.java:395) ~[Paper-1.12.2-v1613.jar:git-Paper-1613]
        at org.bukkit.craftbukkit.v1_12_R1.CraftServer.enablePlugins(CraftServer.java:344) ~[Paper-1.12.2-v1613.jar:git-Paper-1613]
        at net.minecraft.server.v1_12_R1.MinecraftServer.t(MinecraftServer.java:442) ~[Paper-1.12.2-v1613.jar:git-Paper-1613]
        at net.minecraft.server.v1_12_R1.MinecraftServer.l(MinecraftServer.java:403) ~[Paper-1.12.2-v1613.jar:git-Paper-1613]
        at net.minecraft.server.v1_12_R1.MinecraftServer.a(MinecraftServer.java:341) ~[Paper-1.12.2-v1613.jar:git-Paper-1613]
        at net.minecraft.server.v1_12_R1.DedicatedServer.init(DedicatedServer.java:289) ~[Paper-1.12.2-v1613.jar:git-Paper-1613]
        at net.minecraft.server.v1_12_R1.MinecraftServer.run(MinecraftServer.java:616) ~[Paper-1.12.2-v1613.jar:git-Paper-1613]
        at java.lang.Thread.run(Thread.java:748) [?:1.8.0_191]