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[Linux] [0.12] [Legacy Minecraft Support] Log4j missing when launching run config in <=1.12.2

See original GitHub issue

The game still run but most log doesn’t appear and there is an error message as the first log. 1.7.10:

ERROR StatusLogger Unable to create class org.apache.logging.log4j.core.impl.Log4jContextFactory specified in jar:file:/home/arthur/.gradle/caches/fabric-loom/1.7.10/net.fabricmc.yarn.1_7_10.1.7.10+build.202206171820-v2/minecraft-merged-named.jar!/META-INF/log4j-provider.properties
 java.lang.ClassNotFoundException: can't load class org.apache.logging.log4j.core.impl.Log4jContextFactory at /home/arthur/.gradle/caches/modules-2/files-2.1/org.apache.logging.log4j/log4j-core/2.8.1/4ac28ff2f1ddf05dae3043a190451e8c46b73c31/log4j-core-2.8.1.jar as it hasn't been exposed to the game (yet? The system property fabric.classPathGroups may not be set correctly in-dev)
	at net.fabricmc.loader.impl.launch.knot.KnotClassDelegate.loadClass(KnotClassDelegate.java:240)
	at net.fabricmc.loader.impl.launch.knot.KnotClassLoader.loadClass(KnotClassLoader.java:145)
	at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:520)
	at org.apache.logging.log4j.spi.Provider.loadLoggerContextFactory(Provider.java:96)
	at org.apache.logging.log4j.LogManager.<clinit>(LogManager.java:91)
	at net.fabricmc.loader.impl.game.minecraft.Log4jLogHandler.patchJndi(Log4jLogHandler.java:113)
	at net.fabricmc.loader.impl.game.minecraft.Log4jLogHandler.<clinit>(Log4jLogHandler.java:80)
	at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
	at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:77)
	at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
	at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:499)
	at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:480)
	at net.fabricmc.loader.impl.game.minecraft.MinecraftGameProvider.setupLogHandler(MinecraftGameProvider.java:367)
	at net.fabricmc.loader.impl.game.minecraft.MinecraftGameProvider.initialize(MinecraftGameProvider.java:338)
	at net.fabricmc.loader.impl.launch.knot.Knot.init(Knot.java:142)
	at net.fabricmc.loader.impl.launch.knot.Knot.launch(Knot.java:68)
	at net.fabricmc.loader.impl.launch.knot.KnotClient.main(KnotClient.java:23)
	at net.fabricmc.devlaunchinjector.Main.main(Main.java:86)
ERROR StatusLogger Unable to create class org.apache.logging.log4j.core.impl.Log4jContextFactory specified in jar:file:/home/arthur/.gradle/caches/modules-2/files-2.1/org.apache.logging.log4j/log4j-core/2.8.1/4ac28ff2f1ddf05dae3043a190451e8c46b73c31/log4j-core-2.8.1.jar!/META-INF/log4j-provider.properties
 java.lang.ClassNotFoundException: can't load class org.apache.logging.log4j.core.impl.Log4jContextFactory at /home/arthur/.gradle/caches/modules-2/files-2.1/org.apache.logging.log4j/log4j-core/2.8.1/4ac28ff2f1ddf05dae3043a190451e8c46b73c31/log4j-core-2.8.1.jar as it hasn't been exposed to the game (yet? The system property fabric.classPathGroups may not be set correctly in-dev)
	at net.fabricmc.loader.impl.launch.knot.KnotClassDelegate.loadClass(KnotClassDelegate.java:240)
	at net.fabricmc.loader.impl.launch.knot.KnotClassLoader.loadClass(KnotClassLoader.java:145)
	at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:520)
	at org.apache.logging.log4j.spi.Provider.loadLoggerContextFactory(Provider.java:96)
	at org.apache.logging.log4j.LogManager.<clinit>(LogManager.java:91)
	at net.fabricmc.loader.impl.game.minecraft.Log4jLogHandler.patchJndi(Log4jLogHandler.java:113)
	at net.fabricmc.loader.impl.game.minecraft.Log4jLogHandler.<clinit>(Log4jLogHandler.java:80)
	at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
	at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:77)
	at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
	at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:499)
	at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:480)
	at net.fabricmc.loader.impl.game.minecraft.MinecraftGameProvider.setupLogHandler(MinecraftGameProvider.java:367)
	at net.fabricmc.loader.impl.game.minecraft.MinecraftGameProvider.initialize(MinecraftGameProvider.java:338)
	at net.fabricmc.loader.impl.launch.knot.Knot.init(Knot.java:142)
	at net.fabricmc.loader.impl.launch.knot.Knot.launch(Knot.java:68)
	at net.fabricmc.loader.impl.launch.knot.KnotClient.main(KnotClient.java:23)
	at net.fabricmc.devlaunchinjector.Main.main(Main.java:86)
ERROR StatusLogger Log4j2 could not find a logging implementation. Please add log4j-core to the classpath. Using SimpleLogger to log to the console...

1.12.2:

ERROR StatusLogger Unable to create class org.apache.logging.log4j.core.impl.Log4jContextFactory specified in jar:file:/home/arthur/.gradle/caches/fabric-loom/1.12.2/net.fabricmc.yarn.1_12_2.1.12.2+build.202206171821-v2/minecraft-merged-named.jar!/META-INF/log4j-provider.properties
 java.lang.ClassNotFoundException: can't load class org.apache.logging.log4j.core.impl.Log4jContextFactory at /home/arthur/.gradle/caches/modules-2/files-2.1/org.apache.logging.log4j/log4j-core/2.8.1/4ac28ff2f1ddf05dae3043a190451e8c46b73c31/log4j-core-2.8.1.jar as it hasn't been exposed to the game (yet? The system property fabric.classPathGroups may not be set correctly in-dev)
	at net.fabricmc.loader.impl.launch.knot.KnotClassDelegate.loadClass(KnotClassDelegate.java:240)
	at net.fabricmc.loader.impl.launch.knot.KnotClassLoader.loadClass(KnotClassLoader.java:145)
	at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:520)
	at org.apache.logging.log4j.spi.Provider.loadLoggerContextFactory(Provider.java:96)
	at org.apache.logging.log4j.LogManager.<clinit>(LogManager.java:91)
	at net.fabricmc.loader.impl.game.minecraft.Log4jLogHandler.patchJndi(Log4jLogHandler.java:113)
	at net.fabricmc.loader.impl.game.minecraft.Log4jLogHandler.<clinit>(Log4jLogHandler.java:80)
	at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
	at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:77)
	at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
	at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:499)
	at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:480)
	at net.fabricmc.loader.impl.game.minecraft.MinecraftGameProvider.setupLogHandler(MinecraftGameProvider.java:367)
	at net.fabricmc.loader.impl.game.minecraft.MinecraftGameProvider.initialize(MinecraftGameProvider.java:338)
	at net.fabricmc.loader.impl.launch.knot.Knot.init(Knot.java:142)
	at net.fabricmc.loader.impl.launch.knot.Knot.launch(Knot.java:68)
	at net.fabricmc.loader.impl.launch.knot.KnotClient.main(KnotClient.java:23)
	at net.fabricmc.devlaunchinjector.Main.main(Main.java:86)
ERROR StatusLogger Unable to create class org.apache.logging.log4j.core.impl.Log4jContextFactory specified in jar:file:/home/arthur/.gradle/caches/modules-2/files-2.1/org.apache.logging.log4j/log4j-core/2.8.1/4ac28ff2f1ddf05dae3043a190451e8c46b73c31/log4j-core-2.8.1.jar!/META-INF/log4j-provider.properties
 java.lang.ClassNotFoundException: can't load class org.apache.logging.log4j.core.impl.Log4jContextFactory at /home/arthur/.gradle/caches/modules-2/files-2.1/org.apache.logging.log4j/log4j-core/2.8.1/4ac28ff2f1ddf05dae3043a190451e8c46b73c31/log4j-core-2.8.1.jar as it hasn't been exposed to the game (yet? The system property fabric.classPathGroups may not be set correctly in-dev)
	at net.fabricmc.loader.impl.launch.knot.KnotClassDelegate.loadClass(KnotClassDelegate.java:240)
	at net.fabricmc.loader.impl.launch.knot.KnotClassLoader.loadClass(KnotClassLoader.java:145)
	at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:520)
	at org.apache.logging.log4j.spi.Provider.loadLoggerContextFactory(Provider.java:96)
	at org.apache.logging.log4j.LogManager.<clinit>(LogManager.java:91)
	at net.fabricmc.loader.impl.game.minecraft.Log4jLogHandler.patchJndi(Log4jLogHandler.java:113)
	at net.fabricmc.loader.impl.game.minecraft.Log4jLogHandler.<clinit>(Log4jLogHandler.java:80)
	at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
	at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:77)
	at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
	at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:499)
	at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:480)
	at net.fabricmc.loader.impl.game.minecraft.MinecraftGameProvider.setupLogHandler(MinecraftGameProvider.java:367)
	at net.fabricmc.loader.impl.game.minecraft.MinecraftGameProvider.initialize(MinecraftGameProvider.java:338)
	at net.fabricmc.loader.impl.launch.knot.Knot.init(Knot.java:142)
	at net.fabricmc.loader.impl.launch.knot.Knot.launch(Knot.java:68)
	at net.fabricmc.loader.impl.launch.knot.KnotClient.main(KnotClient.java:23)
	at net.fabricmc.devlaunchinjector.Main.main(Main.java:86)
ERROR StatusLogger Log4j2 could not find a logging implementation. Please add log4j-core to the classpath. Using SimpleLogger to log to the console...

Issue Analytics

  • State:closed
  • Created a year ago
  • Comments:10 (8 by maintainers)

github_iconTop GitHub Comments

1reaction
Juuxelcommented, Jul 20, 2022

Fabric Loader can run on any release version of Minecraft, as well as almost all earlier versions too. Not sure if the later refactors after 2019 and 2020 have broken some versions like Classic though.

0reactions
arthurbamboucommented, Aug 4, 2022

It occurs even when the config is not set though.

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