Optimize for log4j2

[a-marcel]

Hello,

it is possible to make blitz4j compatible with log4j2 ?

I try to start Eureka with log4j2 and get the error:

thanks in advance Marcel

Exception in thread "main" org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.cloud.netflix.eureka.server.EurekaServerInitializerConfiguration': Invocation of init method failed; nested exception is java.lang.VerifyError: class com.netflix.blitz4j.NFLockFreeLogger overrides final method getEffectiveLevel.()Lorg/apache/log4j/Level;
    at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor.postProcessBeforeInitialization(InitDestroyAnnotationBeanPostProcessor.java:136)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyBeanPostProcessorsBeforeInitialization(AbstractAutowireCapableBeanFactory.java:408)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1558)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:539)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:303)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:299)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:755)
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:757)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:480)
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:118)
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:686)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:320)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:957)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:946)
    at eurekademo.EurekaApplication.main(EurekaApplication.java:19)
Caused by: java.lang.VerifyError: class com.netflix.blitz4j.NFLockFreeLogger overrides final method getEffectiveLevel.()Lorg/apache/log4j/Level;
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClass(ClassLoader.java:760)
    at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
    at java.net.URLClassLoader.defineClass(URLClassLoader.java:455)
    at java.net.URLClassLoader.access$100(URLClassLoader.java:73)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:367)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:361)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:360)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClass(ClassLoader.java:760)
    at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
    at java.net.URLClassLoader.defineClass(URLClassLoader.java:455)
    at java.net.URLClassLoader.access$100(URLClassLoader.java:73)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:367)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:361)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:360)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    at org.springframework.cloud.netflix.eureka.server.EurekaServerInitializerConfiguration.initLogging(EurekaServerInitializerConfiguration.java:103)
    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:483)
    at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor$LifecycleElement.invoke(InitDestroyAnnotationBeanPostProcessor.java:349)
    at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor$LifecycleMetadata.invokeInitMethods(InitDestroyAnnotationBeanPostProcessor.java:300)
    at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor.postProcessBeforeInitialization(InitDestroyAnnotationBeanPostProcessor.java:133)
    ... 17 more

[flyinprogrammer]

I too have these similar questions. :+1:

So here is the issue... in the log4j 1.2 api they mark that method as final: https://git-wip-us.apache.org/repos/asf?p=logging-log4j2.git;a=blob;f=log4j-1.2-api/src/main/java/org/apache/log4j/Category.java;h=87da4db547f6d63c4befd3df958b9112edb0df23;hb=HEAD#l158

But in log4j 1.2 it is not marked as final: http://svn.apache.org/viewvc/logging/log4j/trunk/src/main/java/org/apache/log4j/Category.java?view=markup

Off to go do more digging. Why are java loggers so gross...

So you can comment out the override and then you run into this bigger deal - from log4j2 documentation: In Log4j 1.x the Logger Hierarchy was maintained through a relationship between Loggers. In Log4j 2 this relationship no longer exists. Instead, the hierarchy is maintained in the relationship between LoggerConfig objects.

This means that all the NFHierarchy stuff needs to be modified...

At the moment the only reason I really need this is to get Eureka 1.x off of blitz4j which means learning how https://github.com/Netflix/eureka/blob/master/eureka-core/src/main/java/com/netflix/eureka/cluster/PeerEurekaNode.java works...

[a-marcel]

Anything new about this issue ?

[fiunchinho]

I'm interested on this too (or even logback).

[cforce]

Me too .. how can i fix that bug?

[tbak]

With PR https://github.com/Netflix/eureka/pull/714 Eureka no longer depends on blitz4j, and uses only slf4j API. You should be able to plugin log4j2 now.