Alfresco sdk 4.6.0 logger not working

[SanjayBandhniya]

I have created Alfresco sdk 4.6.0 and started(alfresco v7.4.0.1).
I have added some logger.debug("----") in HelloWorldWebScript.java file but its not displaying.
if I change it to logger.error("----") then its working.
I have tried to change rootlogger in dev-log4j.properties to debug, still its not working.
if I change alfresco version to 7.3.0 then its working(no change in log configuration)