Java 9 Compatibility
leNicDev opened this issue · 11 comments
When using the latest Java 9 EA JDK I'm getting the following error when LuckPerms gets loaded:
[13:55:51] [Server thread/INFO]: [LuckPerms] Loading LuckPerms v3.4.6
[13:55:51] [Server thread/INFO]: �[0;37;22m�[21m[�[0;36;1mL�[0;36;22mP�[0;37;22m�[21m] �[0;36;22mIdentified the following dependencies: [CAFFEINE]�[m
[13:55:51] [Server thread/INFO]: �[0;37;22m�[21m[�[0;36;1mLuck�[0;36;22mPerms�[0;37;22m�[21m] �[0;31;22m[ERROR] Failed to load jar for dependency CAFFEINE�[m
[13:55:51] [Server thread/WARN]: java.lang.ClassCastException: java.base/jdk.internal.loader.ClassLoaders$AppClassLoader cannot be cast to java.base/java.net.URLClassLoader
[13:55:51] [Server thread/WARN]: at me.lucko.luckperms.common.dependencies.DependencyManager.loadJar(DependencyManager.java:141)
[13:55:51] [Server thread/WARN]: at me.lucko.luckperms.common.dependencies.DependencyManager.loadDependencies(DependencyManager.java:106)
[13:55:51] [Server thread/WARN]: at me.lucko.luckperms.bukkit.LPBukkitPlugin.onLoad(LPBukkitPlugin.java:154)
[13:55:51] [Server thread/WARN]: at org.bukkit.craftbukkit.v1_12_R1.CraftServer.loadPlugins(CraftServer.java:313)
[13:55:51] [Server thread/WARN]: at net.minecraft.server.v1_12_R1.DedicatedServer.init(DedicatedServer.java:205)
[13:55:51] [Server thread/WARN]: at net.minecraft.server.v1_12_R1.MinecraftServer.run(MinecraftServer.java:545)
[13:55:51] [Server thread/WARN]: at java.base/java.lang.Thread.run(Thread.java:844)
Java 9 is released in 4 days and should be supported by LuckPerms.
For end users, should we be sticking with Java 8 to run minecrafter server? Or should Java 9 work for it? We've upgraded, and seem to be noticing a big of lag. (mainly on chests and bows)
Side note: Java 9 works perfectly for us. We've even seen minor improvements. We have been running it for months.
... and seem to be noticing a big of lag.
Must be a worldprotect/logging plugin or something. An official released JRE should not cause that.
I've got to apologize at this point. I accidentally posted my original comment after I found this thread via google, without checking what it was in. We are actually running a pure-vanilla server at the moment, no plugins of any kind. Sorry for distracting everyone on a question that isn't actually related to your mod work here.
That being said, if Java 9 is actually improving your performance, I'm interested in knowing what sort of java parameters you are using when you launch MC.
Mind testing a build for me @leNicDev? I don't have the new JRE downloaded yet.
Using the test build, an additional exception gets thrown:
[19:30:27] [Server thread/INFO]: [LuckPerms] Loading LuckPerms v3.4.6
[19:30:27] [Server thread/ERROR]: null initializing LuckPerms v3.4.6 (Is it up to date?)
java.lang.ExceptionInInitializerError: null
at me.lucko.luckperms.bukkit.LPBukkitPlugin.onLoad(LPBukkitPlugin.java:154) ~[?:?]
at org.bukkit.craftbukkit.v1_12_R1.CraftServer.loadPlugins(CraftServer.java:313) [spigot-1.12.1.jar:git-Spigot-da42974-8f47214]
at net.minecraft.server.v1_12_R1.DedicatedServer.init(DedicatedServer.java:205) [spigot-1.12.1.jar:git-Spigot-da42974-8f47214]
at net.minecraft.server.v1_12_R1.MinecraftServer.run(MinecraftServer.java:545) [spigot-1.12.1.jar:git-Spigot-da42974-8f47214]
at java.lang.Thread.run(Unknown Source) [?:?]
Caused by: java.lang.reflect.InaccessibleObjectException: Unable to make field private final jdk.internal.loader.URLClassPath jdk.internal.loader.BuiltinClassLoader.ucp accessible: module java.base does not "opens jdk.internal.loader" to unnamed module @2fe64285
at java.lang.reflect.AccessibleObject.checkCanSetAccessible(Unknown Source) ~[?:?]
at java.lang.reflect.AccessibleObject.checkCanSetAccessible(Unknown Source) ~[?:?]
at java.lang.reflect.Field.checkCanSetAccessible(Unknown Source) ~[?:?]
at java.lang.reflect.Field.setAccessible(Unknown Source) ~[?:?]
at me.lucko.luckperms.common.dependencies.DependencyManager.<clinit>(DependencyManager.java:86) ~[?:?]
... 5 more
[19:30:27] [Server thread/INFO]: [LuckPerms] Enabling LuckPerms v3.4.6
[19:30:27] [Server thread/INFO]: �[0;36;1m __ �[0;36;22m __ ___ __ __ �[m
[19:30:27] [Server thread/INFO]: �[0;36;1m | | | / ` |__/ �[0;36;22m|__) |__ |__) |\/| /__` �[m
[19:30:27] [Server thread/INFO]: �[0;36;1m |___ \__/ \__, | \ �[0;36;22m| |___ | \ | | .__/ �[m
[19:30:27] [Server thread/INFO]: �[m
[19:30:27] [Server thread/INFO]: �[0;32;22m Loading version �[0;36;1mv3.4.6�[0;32;22m on Bukkit - CraftBukkit�[m
[19:30:27] [Server thread/INFO]: �[0;30;1m Running on server version git-Spigot-da42974-8f47214 (MC: 1.12.1) - 1.12.1-R0.1-SNAPSHOT�[m
[19:30:27] [Server thread/INFO]: �[m
[19:30:27] [Server thread/INFO]: �[0;37;22m�[21m[�[0;36;1mL�[0;36;22mP�[0;37;22m�[21m] �[0;36;22mLoading configuration...�[m
[19:30:27] [Server thread/ERROR]: Error occurred while enabling LuckPerms v3.4.6 (Is it up to date?)
java.lang.NoClassDefFoundError: com/github/benmanes/caffeine/cache/Caffeine
at me.lucko.luckperms.common.config.AbstractConfiguration.<init>(AbstractConfiguration.java:47) ~[?:?]
at me.lucko.luckperms.bukkit.BukkitConfig.<init>(BukkitConfig.java:43) ~[?:?]
at me.lucko.luckperms.bukkit.LPBukkitPlugin.enable(LPBukkitPlugin.java:189) ~[?:?]
at me.lucko.luckperms.bukkit.LPBukkitPlugin.onEnable(LPBukkitPlugin.java:172) ~[?:?]
at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:264) ~[spigot-1.12.1.jar:git-Spigot-da42974-8f47214]
at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:337) [spigot-1.12.1.jar:git-Spigot-da42974-8f47214]
at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:402) [spigot-1.12.1.jar:git-Spigot-da42974-8f47214]
at org.bukkit.craftbukkit.v1_12_R1.CraftServer.enablePlugin(CraftServer.java:384) [spigot-1.12.1.jar:git-Spigot-da42974-8f47214]
at org.bukkit.craftbukkit.v1_12_R1.CraftServer.enablePlugins(CraftServer.java:333) [spigot-1.12.1.jar:git-Spigot-da42974-8f47214]
at net.minecraft.server.v1_12_R1.DedicatedServer.init(DedicatedServer.java:206) [spigot-1.12.1.jar:git-Spigot-da42974-8f47214]
at net.minecraft.server.v1_12_R1.MinecraftServer.run(MinecraftServer.java:545) [spigot-1.12.1.jar:git-Spigot-da42974-8f47214]
at java.lang.Thread.run(Unknown Source) [?:?]
Caused by: java.lang.ClassNotFoundException: com.github.benmanes.caffeine.cache.Caffeine
at java.net.URLClassLoader.findClass(Unknown Source) ~[?:?]
at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:101) ~[spigot-1.12.1.jar:git-Spigot-da42974-8f47214]
at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:86) ~[spigot-1.12.1.jar:git-Spigot-da42974-8f47214]
at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:?]
at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:?]
... 12 more
Looks like LuckPerms is accessing an internal JDK class which has been moved to an external module.
Yes it is.
In Java 9, the system classloader is no longer an instance of URLClassLoader, which means LuckPerms cannot inject it's dependencies there.
They're now an instance of BuiltinClassLoader, which yeah, is an internal class.
It seems like we can work around the issue by injecting into the plugin classloader, since all implementations use some form of URLClassLoader to load plugins.
Let me know if it works. (I'm fairly confident it will 😄 )
