Could not load 'plugins/RealisticWorldGenerator-4.34.7.jar' in folder 'plugins'

[ForzovOVH]

[07:25:44 ERROR]: Could not load 'plugins/RealisticWorldGenerator-4.34.7.jar' in folder 'plugins'
org.bukkit.plugin.InvalidPluginException: java.lang.UnsupportedClassVersionError: net/sourcewriters/spigot/rwg/legacy/Realistic has been compiled by a more recent version of the Java Runtime (class file version 60.0), this version of the Java Runtime only recognizes class file versions up to 55.0
at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:131) ~[patched_1.12.2.jar:git-Paper-1618]
at org.bukkit.plugin.SimplePluginManager.loadPlugin(SimplePluginManager.java:329) ~[patched_1.12.2.jar:git-Paper-1618]
at org.bukkit.plugin.SimplePluginManager.loadPlugins(SimplePluginManager.java:251) ~[patched_1.12.2.jar:git-Paper-1618]
at org.bukkit.craftbukkit.v1_12_R1.CraftServer.loadPlugins(CraftServer.java:318) ~[patched_1.12.2.jar:git-Paper-1618]
at net.minecraft.server.v1_12_R1.DedicatedServer.init(DedicatedServer.java:222) ~[patched_1.12.2.jar:git-Paper-1618]
at net.minecraft.server.v1_12_R1.MinecraftServer.run(MinecraftServer.java:616) ~[patched_1.12.2.jar:git-Paper-1618]
at java.lang.Thread.run(Thread.java:829) [?:?]
Caused by: java.lang.UnsupportedClassVersionError: net/sourcewriters/spigot/rwg/legacy/Realistic has been compiled by a more recent version of the Java Runtime (class file version 60.0), this version of the Java Runtime only recognizes class file versions up to 55.0
at java.lang.ClassLoader.defineClass1(Native Method) ~[?:?]
at java.lang.ClassLoader.defineClass(ClassLoader.java:1017) ~[?:?]
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:174) ~[?:?]
at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:152) ~[patched_1.12.2.jar:git-Paper-1618]
at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:104) ~[patched_1.12.2.jar:git-Paper-1618]
at java.lang.ClassLoader.loadClass(ClassLoader.java:589) ~[?:?]
at java.lang.ClassLoader.loadClass(ClassLoader.java:522) ~[?:?]
at java.lang.Class.forName0(Native Method) ~[?:?]
at java.lang.Class.forName(Class.java:398) ~[?:?]
at org.bukkit.plugin.java.PluginClassLoader.<init>(PluginClassLoader.java:82) ~[patched_1.12.2.jar:git-Paper-1618]
at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:127) ~[patched_1.12.2.jar:git-Paper-1618]
... 6 more

 

[ChatGPT ?]

The error message indicates that the plugin 'RealisticWorldGenerator-4.34.7.jar' could not be loaded because it was compiled with a newer version of Java Runtime (class file version 60.0) than the server is currently running (class file version up to 55.0). To fix this issue, you will need to update your server's Java Runtime to a version that supports class file version 60.0. Alternatively, you can try to find a version of the plugin that is compatible with your server's current Java Runtime version.