Actions, Determinations and Validations

Explanation

Actions, determinations and validations are key RAP behavior concepts. An action is triggered explicitly by a user or consumer, such as approve, reject or submit. A determination automatically derives or changes values during modify or save, such as setting default status or calculating total amount. A validation checks business rules and reports errors, such as preventing approval when amount exceeds a limit. Mixing these concepts is a common beginner mistake. Use the correct hook so that behavior remains predictable and easy to test.

Code example

define behavior for ZI_Expense alias Expensepersistent table zexpenselock master{ create; update;  determination setReviewer on modify { create; update; } validation validateAmount on save { create; update; } action submit result [1] $self;} * Determination:* Automatically sets reviewer based on department. * Validation:* Stops save if amount violates policy. * Action:* User explicitly clicks Submit to move status forward.

Real project scenario

An expense report app used validation to enforce policy limits, a determination to auto-set reviewer based on department and an action to submit the report for approval.

Common mistakes

- Using validation to fill default values. - Using determination to raise business errors. - Using action for logic that should happen automatically. - Not returning clear messages from validations.

Best practices

- Use determinations for derived values. - Use validations for rule checks. - Use actions for explicit business commands. - Return clear user-friendly messages.

Interview angle

Interviewers ask this often. Answer must clearly separate when to use action, determination and validation.