[LOG4J2-2050] NullPointerException in LogManager.getLogger when called from anonymous class initializer

• Type: Bug
• Status: Closed
• Priority: Critical
• Resolution: Fixed
• Affects Version/s: 2.9.0
• Fix Version/s: 2.9.1
• Component/s: Core
• Assignee: Unassigned
• Reporter: Mark Arnold
• Created: 13/Sep/17 22:42
• Updated: 14/Sep/17 12:45
• Resolved: 14/Sep/17 01:47

Description

I observed a NullPointerException when calling LogManager.getLogger in the initializer block of an anonymous class, like so:

		SomeInterface _t = new SomeInterface() {
			Logger log = LogManager.getLogger();
			@Override
			public String someMethod() {
				log.info("Logging...");
				return "";
			}
		};

This did work fine in 2.8.2, but 2.9.0 gets an NPE:

java.lang.NullPointerException
	at java.util.concurrent.ConcurrentHashMap.get(ConcurrentHashMap.java:936)
	at org.apache.logging.log4j.spi.LoggerRegistry.getLogger(LoggerRegistry.java:125)
	at org.apache.logging.log4j.core.LoggerContext.getLogger(LoggerContext.java:447)
	at org.apache.logging.log4j.core.LoggerContext.getLogger(LoggerContext.java:420)
	at org.apache.logging.log4j.core.LoggerContext.getLogger(LoggerContext.java:60)
	at org.apache.logging.log4j.LogManager.getLogger(LogManager.java:551)
	at org.apache.logging.log4j.LogManager.getLogger(LogManager.java:537)
	at LibraryTest$1.<init>(LibraryTest.java:11)
	at LibraryTest.testGetLoggerFromAnonymousInnerClass_inInitializer(LibraryTest.java:10)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
	at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
	at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
	at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
	at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
	at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
	at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
	at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
	at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
	at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
	at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
	at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:86)
	at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:459)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:678)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:382)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:192)

The error does not occur when I move the call of LogManager.getLogger() down inside of
someMethod(). It only happens when called from the initializer block.

Issue Links

• is related to: LOG4J2-2023 Use a class' canonical name instead of name to create its logger name