Question

I have a Liferay setup on the Tomcat6. I used Log4j initially for portlets/webapps by adding log4j.properties file in the classes folder and log4j.jar file in the web-inf/lib.

Now we have few quartz jobs which are available in the tomcat/lib folder and I want to enable log4j logging for these jobs as well.

For these quartz jobs I have copied same log4j.properties file in the tomcat/lib.

With the new configuration I keep getting the following error:

Could not instantiate appender named "JOBS"
A "org.apache.log4j.RollingFileAppender" is not assignable a "org.apache.log4j.Appender" variable.
The class "org.apache.log4j.Appender" was loaded by ...

How to remove this error?

Is there any way I can keep a single log4j.properties file which can be used by both shared/lib as well as portlet/webapps.

Answer 1

According to this post the problem is that you have configured your log4j twice.

My solution would be that you create the logger instance like this

private static Logger logger = Logger.getLogger(FooBar.class.getName());

and not to have log4j.properties under any lib or class folder but having it under a folder named resources.

AFAIK this should be a place where the both parts of your application may have access to.