ich habe ein plugin nach ein tutorial erstellt und als ich meinen testserver starten wollte kahm die meldung : [20:22:09 INFO]: Using default channel type [20:22:09 INFO]: Set PluginClassLoader as parallel capable [20:22:09 ERROR]: Could not load 'plugins\test.jar' in folder 'plugins' org.bukkit.plugin.InvalidPluginException: java.lang.UnsupportedClassVersionError: de/ifreeaple/test/main/Main has been compiled by a more recent version of the Java Runtime (class file version 56.0), this version of the Java Runtime only recognizes class file versions up to 52.0 at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:133) ~[spigot.jar:git-Spigot-dcd1643-e60fc34] at org.bukkit.plugin.SimplePluginManager.loadPlugin(SimplePluginManager.java:327) ~[spigot.jar:git-Spigot-dcd1643-e60fc34] at org.bukkit.plugin.SimplePluginManager.loadPlugins(SimplePluginManager.java:248) [spigot.jar:git-Spigot-dcd1643-e60fc34] at org.bukkit.craftbukkit.v1_12_R1.CraftServer.loadPlugins(CraftServer.java:305) [spigot.jar:git-Spigot-dcd1643-e60fc34] at net.minecraft.server.v1_12_R1.DedicatedServer.init(DedicatedServer.java:205) [spigot.jar:git-Spigot-dcd1643-e60fc34] at net.minecraft.server.v1_12_R1.MinecraftServer.run(MinecraftServer.java:545) [spigot.jar:git-Spigot-dcd1643-e60fc34] at java.lang.Thread.run(Unknown Source) [?:1.8.0_211] Caused by: java.lang.UnsupportedClassVersionError: de/ifreeaple/test/main/Main has been compiled by a more recent version of the Java Runtime (class file version 56.0), this version of the Java Runtime only recognizes class file versions up to 52.0 at java.lang.ClassLoader.defineClass1(Native Method) ~[?:1.8.0_211] at java.lang.ClassLoader.defineClass(Unknown Source) ~[?:1.8.0_211] at java.security.SecureClassLoader.defineClass(Unknown Source) ~[?:1.8.0_211] at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:148) ~[spigot.jar:git-Spigot-dcd1643-e60fc34] at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:100) ~[spigot.jar:git-Spigot-dcd1643-e60fc34] at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_211] at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_211] at java.lang.Class.forName0(Native Method) ~[?:1.8.0_211] at java.lang.Class.forName(Unknown Source) ~[?:1.8.0_211] at org.bukkit.plugin.java.PluginClassLoader.<init>(PluginClassLoader.java:78) ~[spigot.jar:git-Spigot-dcd1643-e60fc34] at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:129) ~[spigot.jar:git-Spigot-dcd1643-e60fc34] ... 6 more
@Ifreeaple You compiled with java a lot and you are running with java 8 / 9. Compile with a lower target.