Answer

The Apache Commons Logging provides a high level interface class to allow developers to write to log stream abstracting the logging implementation. The Commons Logging Framework can automatically find & configure it self to an available logging implementation or it can be configure by specifying a logging implementation e.g. Log4j by adding the following properties in commons-logging.properties file.

org.apache.commons.logging.Log=org.apache.commons.logging.impl.Log4JLogger
org.apache.commons.logging.LogFactory=org.apache.commons.logging.impl.LogFactoryImpl

Please make sure this file is in the class path, rest it will configure automatically.