DMP to exceute to a particular Entity or Set of Entities?

Hi BPC Gurus,

    I am working on the customised BADI and for the same in the DMP I want to apply the BADI to a particular ENTITY or group of ENTITIES. Currently the logic is getting executed to all the entities.

   I have tried Parameters in the LOGIC but every time the USER has to Enter manually the Entity name. Instead like in standard I want the selection which is system based and the Logic gets executed to that particular selection.

Regards

KMG