Rule Definition
Instead of being stick to a specific logging implementation, it is recommended to use the logging wrapper Jakarta commons-logging. It provides a Log interface that is intended to be both light-weight and an independent abstraction of other logging toolkits. It provides the middleware/tooling developer with a simple logging abstraction that allows the user (application developer) to plug in a specific logging implementation.

Remediation
Use SLF4J http://www.slf4j.org/index.html instead and configure it to use your specific logging implementation.

Violation Code Sample

import org.apache.log4j.*
Logger  logger = Logger.getLogger("com.cast"); // VIOLATION

Fixed Code Sample

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
Log log = LogFactory.getLog("com.cast"); // FIXED

http://www.infoq.com/news/2007/02/javaee-best-practices