IncompatibleClassChangeError on <1.13 Server's

[uRyanxD]

This happens in all versions lower than 1.13 due to the lack of support for plugins using their own logger.

Support for this was only added in 1.13:
https://hub.spigotmc.org/stash/projects/SPIGOT/repos/bukkit/commits/0279d9b41516e1fa566848cc5affdd0fca0028de#src/main/java/org/bukkit/plugin/java/JavaPlugin.java

[12:24:03 ERROR]: Could not load 'plugins\TCPShield-2.8.1.jar' in folder 'plugins'
org.bukkit.plugin.InvalidPluginException: java.lang.IncompatibleClassChangeError: class net.tcpshield.tcpshield.bukkit.TCPShieldBukkit overrides final method org.bukkit.plugin.java.JavaPlugin.getLogger()Ljava/util/logging/Logger;
at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:133) ~[server.jar:git-PandaSpigot-"9acb0e6"]
at org.bukkit.plugin.SimplePluginManager.loadPlugin(SimplePluginManager.java:340) ~[server.jar:git-PandaSpigot-"9acb0e6"]
at org.bukkit.plugin.SimplePluginManager.loadPlugins(SimplePluginManager.java:263) [server.jar:git-PandaSpigot-"9acb0e6"]
at org.bukkit.craftbukkit.v1_8_R3.CraftServer.loadPlugins(CraftServer.java:297) [server.jar:git-PandaSpigot-"9acb0e6"]
at net.minecraft.server.v1_8_R3.DedicatedServer.init(DedicatedServer.java:236) [server.jar:git-PandaSpigot-"9acb0e6"]
at net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java:580) [server.jar:git-PandaSpigot-"9acb0e6"]
at java.base/java.lang.Thread.run(Thread.java:840) [?:?]
Caused by: java.lang.IncompatibleClassChangeError: class net.tcpshield.tcpshield.bukkit.TCPShieldBukkit overrides final method org.bukkit.plugin.java.JavaPlugin.getLogger()Ljava/util/logging/Logger;
at java.base/java.lang.ClassLoader.defineClass1(Native Method) ~[?:?]
at java.base/java.lang.ClassLoader.defineClass(ClassLoader.java:1017) ~[?:?]
at java.base/java.security.SecureClassLoader.defineClass(SecureClassLoader.java:150) ~[?:?]
at java.base/java.net.URLClassLoader.defineClass(URLClassLoader.java:524) ~[?:?]
at java.base/java.net.URLClassLoader$1.run(URLClassLoader.java:427) ~[?:?]
at java.base/java.net.URLClassLoader$1.run(URLClassLoader.java:421) ~[?:?]
at java.base/java.security.AccessController.doPrivileged(AccessController.java:712) ~[?:?]
at java.base/java.net.URLClassLoader.findClass(URLClassLoader.java:420) ~[?:?]
at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:102) ~[server.jar:git-PandaSpigot-"9acb0e6"]
at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:87) ~[server.jar:git-PandaSpigot-"9acb0e6"]
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:592) ~[?:?]
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:525) ~[?:?]
at java.base/java.lang.Class.forName0(Native Method) ~[?:?]
at java.base/java.lang.Class.forName(Class.java:467) ~[?:?]
at org.bukkit.plugin.java.PluginClassLoader.(PluginClassLoader.java:65) ~[server.jar:git-PandaSpigot-"9acb0e6"]
at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:129) ~[server.jar:git-PandaSpigot-"9acb0e6"]
... 6 more

[uRyanxD]

I believe the issue was introduced in 554d6c3#diff-b3cbe97b09884c36b11f3bfdae5c7ea1c37bff8d30cadf3d38a515a4f4e3685aR95