java.lang.NoClassDefFoundError: com/day/cq/commons/Externalizer

I have developed a website using AEM 6.1 API. In some piece of java code, I used the Externalizer class from AEM (com.day.cq.commons). This piece of code worked fine in 6.1 aem instance. When tried to deploy on AEM 6.2 got below error.

06.07.2017 09:55:54.242 *ERROR* [0:0:0:0:0:0:0:1 [1499331350444] GET /content/kishore/en/test.html HTTP/1.1] com.day.cq.wcm.core.impl.WCMDebugFilter Exception: com/day/cq/commons/Externalizer java.lang.NoClassDefFoundError: com/day/cq/commons/Externalizer

Solution:
Fixed this issue by rebuilding the package with AEM 6.2 uber.jar