[logback-user] commons-logging -> sl4j -> logback

In a previous project I switched from commons-logging -> log4j to sl4j -> logback. One of the reasons I did that was the overhead in log4j when providing a object in the log... log.debug("This is a object" + object); would cause the object.toString to be called even debug was not enabled. Now I work on a new project that uses commons-logging -> sl4j -> logback (jcl-over-slf4j) My question is now, will this still call object.toString.. even debug is not enabled import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; .... log.debug("This is a object" + object); I would like to get rid of commons-logging and jcl-over.sl4j and only have sl4j and logback.