Compatibility with SLF4J

[veetow]

I'm trying to get this layout working with Solr, and I'm hitting issues because of what's been noted in issues 25 and 26 combined with the fact that SLF4J bindings for log4j version 1.2 (https://wiki.apache.org/solr/SolrLogging) require you to "place log4j.jar on your class path" (http://www.slf4j.org/manual.html).

Unsurprisingly, given the above, I'm getting this error on startup:

SLF4J: Class path contains multiple SLF4J bindings.
SLF4J: Found binding in [jar:file:/server/tomcat/lib/slf4j-log4j12-1.7.6.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [jar:file:/server/tomcat/webapps/solr/WEB-INF/lib/activemq-all-5.10.0.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [jar:file:/server/tomcat/webapps/solr/WEB-INF/lib/slf4j-log4j12-1.7.6.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: See http://www.slf4j.org/codes.html#multiple_bindings for an explanation.
SLF4J: Actual binding is of type [org.slf4j.impl.Log4jLoggerFactory]
log4j:WARN Error during default initialization
java.lang.NoClassDefFoundError: org/apache/log4j/Layout
        at java.lang.ClassLoader.defineClass1(Native Method)
        at java.lang.ClassLoader.defineClass(ClassLoader.java:791)
        at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
        at java.net.URLClassLoader.defineClass(URLClassLoader.java:449)
        at java.net.URLClassLoader.access$100(URLClassLoader.java:71)
        at java.net.URLClassLoader$1.run(URLClassLoader.java:361)
        at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:423)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:356)
        at java.lang.Class.forName0(Native Method)
        at java.lang.Class.forName(Class.java:266)
        at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1707)
        at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1571)
        at java.lang.Class.forName0(Native Method)
        at java.lang.Class.forName(Class.java:188)
        at org.apache.log4j.helpers.Loader.loadClass(Loader.java:198)
        at org.apache.log4j.helpers.OptionConverter.instantiateByClassName(OptionConverter.java:327)
        at org.apache.log4j.helpers.OptionConverter.instantiateByKey(OptionConverter.java:124)
        at org.apache.log4j.PropertyConfigurator.parseAppender(PropertyConfigurator.java:797)
        at org.apache.log4j.PropertyConfigurator.parseCategory(PropertyConfigurator.java:768)
        at org.apache.log4j.PropertyConfigurator.configureRootCategory(PropertyConfigurator.java:648)
        at org.apache.log4j.PropertyConfigurator.doConfigure(PropertyConfigurator.java:514)
        at org.apache.log4j.PropertyConfigurator.doConfigure(PropertyConfigurator.java:580)
        at org.apache.log4j.helpers.OptionConverter.selectAndConfigure(OptionConverter.java:526)
        at org.apache.log4j.LogManager.<clinit>(LogManager.java:127)
        at org.slf4j.impl.Log4jLoggerFactory.getLogger(Log4jLoggerFactory.java:66)
        at org.slf4j.LoggerFactory.getLogger(LoggerFactory.java:270)
        at org.slf4j.LoggerFactory.getLogger(LoggerFactory.java:281)
        at org.apache.solr.servlet.CheckLoggingConfiguration.check(CheckLoggingConfiguration.java:26)
        at org.apache.solr.servlet.BaseSolrFilter.<clinit>(BaseSolrFilter.java:31)
        at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
        at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
        at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
        at java.lang.reflect.Constructor.newInstance(Constructor.java:525)
        at java.lang.Class.newInstance0(Class.java:374)
        at java.lang.Class.newInstance(Class.java:327)
        at org.apache.catalina.core.DefaultInstanceManager.newInstance(DefaultInstanceManager.java:140)
        at org.apache.catalina.core.ApplicationFilterConfig.getFilter(ApplicationFilterConfig.java:258)
        at org.apache.catalina.core.ApplicationFilterConfig.<init>(ApplicationFilterConfig.java:105)
        at org.apache.catalina.core.StandardContext.filterStart(StandardContext.java:4809)
        at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5485)
        at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
        at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:901)
        at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:877)
        at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:632)
        at org.apache.catalina.startup.HostConfig.deployDescriptor(HostConfig.java:670)
        at org.apache.catalina.startup.HostConfig$DeployDescriptor.run(HostConfig.java:1839)
        at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
        at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
        at java.util.concurrent.FutureTask.run(FutureTask.java:166)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
        at java.lang.Thread.run(Thread.java:722)
Caused by: java.lang.ClassNotFoundException: org.apache.log4j.Layout
        at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
        at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:423)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:356)
        ... 55 more

Any advice on what approach I should take to get your log4j layout working with SLF4J 1.7.6?

[MatthiasLohr]

Anything new here? I'm running in the same problem...