log4j startup exception

[MikeTempleman]

Intermittently log4j throws a nullpointexception when starting up our Grails app. From the stacktrace, we can see that setLevelAndAppender(Level level, Object[] appenders) is called with a null appender array. Walking up the stacktrace we can see the error occurs when the root closure is invoked.

I have tried cleaning the project, multiple refresh dependencies, shutting down STS, tossing all the log files and making some cosmetic changes in config.groovy--none of which seem to work.

Here is the log4j setup in config. If someone can see an obvious mistake in it, could you let me know?

// log4j configuration
log4j = {
		error  'org.codehaus.groovy.grails.web.servlet',  //  controllers
				'org.codehaus.groovy.grails.web.pages', //  GSP
				'org.codehaus.groovy.grails.web.sitemesh', //  layouts
				'org.codehaus.groovy.grails.web.mapping.filter', // URL mapping
				'org.codehaus.groovy.grails.web.mapping', // URL mapping
				'org.codehaus.groovy.grails.commons', // core / classloading
				'org.codehaus.groovy.grails.plugins', // plugins
				'org.codehaus.groovy.grails.orm.hibernate', // hibernate integration
				'org.springframework',
				'org.hibernate',
				'net.sf.ehcache.hibernate'
	
		warn   'org.mortbay.log'

	appenders {
			console name:'stdout', layout:pattern(conversionPattern: '%d{ISO8601} %-5p [%c{1}] - %m%n' ), threshold:org.apache.log4j.Level.DEBUG
				rollingFile name:'stacktrace', file:"${logDirectory}/${appName}_stacktrace.log".toString(), threshold: org.apache.log4j.Level.ERROR, maxFileSize:2048000
				rollingFile name:'infoLog', file:"${logDirectory}/${appName}_info.log".toString(), threshold: org.apache.log4j.Level.INFO, maxFileSize:2048000
				rollingFile name:'errorLog', file:"${logDirectory}/${appName}_error.log".toString(), threshold: org.apache.log4j.Level.ERROR, maxFileSize:2048000
				rollingFile name:'custom', file:"${logDirectory}/${appName}_custom.log".toString(), maxFileSize:2048000


	}
	root {
				info 'infoLog','warnLog','errorLog', 'stdout'
				debug stdout
				//error 'mail'
				error 'errorLog', stdout
		//warn stdout
		additivity = true
	}
}

[MikeTempleman]

I may have found it. I had 'warnLog' reporting info in the root logger, but had not created an appender for warnLog.