Need Help for Access Classes while Design BoM in MDG

Hello Friends,

               Need Help for Access Class while passing data from Stagging area to Active are for BoM(Bill of material.

               I have an idea of using a standard Interface (IF_USMD_PP_ACCESS) and write code in (IF_USMD_PP_ACCESS~SAVE) Method

               so that this method will call once we Activate our CR.

               But i need to know from Logic point of view...........If anyone have already written code for Access Class to Implements BoM in there project.

               Then Please guide me From Logic point of View how to get data and update in Standard Table of BoM.