Getting Error [java.lang.NullPointerException] while updating initialData

Hi,

I am working on commerce trail and practising Merchandise example with different name called rxshopintialdata. I have configured all the required data as per wiki trail. But the update thorws error saying

INFO [hybrisHTTP31] [Initialization] Error creating sample data for rxshopinitialdata. See console output. ERROR [hybrisHTTP31] [Initialization] java.lang.NullPointerException

I couldn't able to find the object which is throwing null. can someone help me how can I debug to identify the object that throwing null pointer exception during the update.