Journal Validations BPC 7.5

Hello,

If I want to have specific validations for journals in SAP BPC NW 7.5, do they have to be implemented in BW through the transactions UJ_VALIDATIONS with a BADI? Is there another way?

I dont want the users to enter a flow in the journals, which is afterwards calculated by the default logic.

I have tried to implement it with the rule table but it is not possible

Many thanks

Dani