badi-enhancementlisted

# BAdI and Enhancement Patterns **Mental model:** A BAdI is an SAP-sanctioned extension contract — SAP defines an interface at a specific call point; you implement the interface in a Z/Y class. The SAP standard code calls your implementation via a dispatcher. No standard code is modified. Upgrades preserve your logic because the contract (interface) is stable. ## Prerequisites - SAP system access (DEV client with developer key / S/4HANA Cloud ABAP) - Transaction SE18 (BAdI definition) and SE19 (BAdI implementation) - Object name in customer namespace (Z* or Y*) - Transport request assigned (SE09/SE10) - For new Kernel BAdI: ABAP ≥ 7.0 (GET BADI statement) - For new BAdI syntax: ABAP ≥ 7.40 (BADI name directly in code) - ADT/Eclipse recommended for class-based implementation ## BAdI Type Selection - **Classic BAdI** (≤ 7.0): Uses `CL_EXITHANDLER=>GET_INSTANCE`. Deprecated — avoid for new development. - **Kernel BAdI** (≥ 7.0): Uses `GET BADI` statement. Filter support, multiple-use. - **New BAdI** (≥ 7.40): Direct `BADI_NAME` reference. Best: type-safe, filter UI, fallback class. > **Rule:** Always prefer New/Kernel BAdI. Only touch classic BAdI when enhancing existing SAP code that already calls `CL_EXITHANDLER`. ## Step 1 — Find the Right BAdI ```abap " Search BAdI definitions by keyword (SE18 or SQL) SELECT name, descript FROM badi WHERE name LIKE '%MATERIAL%' INTO TABLE @DATA(lt_badis). " Check existing implementations SELECT badi_name, impl_name FROM badi_imp