Reject bad input; derive predictable values

A requested amount must be positive. Separately, a new request can start with an initial status. RAP provides different extension points for these jobs:

• A validation checks data and can report an error that prevents the transaction from saving.
• A determination derives or adjusts data at a defined point in the interaction/save lifecycle.

Declare the trigger conditions

validation validateAmount on save {
  create;
  field RequestedAmount;
}

determination setInitialStatus on modify {
  create;
}

These declarations belong in a behavior definition. Their implementations live in a behavior pool and must populate RAP response information correctly. The exact trigger and implementation logic should follow the BO contract; don’t put a rule in a determination just because it changes data.

For complex behavior, use focused methods and add ABAP Unit coverage. Syntax and available trigger additions depend on the target release.

Sources

• SAP Samples: RAP BDEF validations and determinations
• ABAP Keyword Documentation: RAP validations and determinations

validation validateAmount on save {
  create;
  field RequestedAmount;
}
determination setInitialStatus on modify {
  create;
}