Validation Options for ADF BC Applications
There are various options for handling validation in ADF BC applications:
Business services. You should build in as much validation as you can when creating the business services in order to protect the integrity of the data in the database and to prevent malicious attacks. There are a multitude of opportunities to add validation at the business services level:
Oracle ADF Business Components provides a number of predefined validation rule classes that enable you to add business logic without writing a single line of code, or you can also add programmatic validation.
You can implement validation in the database; however, such validation cannot be exposed in the UI. For example, you cannot use database validation to expose a list of valid values in the UI.
User interface. The ADF Faces input components that you use to build the pages of your application also have built-in validation capabilities. You use these prebuilt ADF Faces validators to ensure that when a user edits or enters data in a field and submits the form, the data is validated against the rules and conditions you have specified. However, UI validation should always have equivalent validation at the business services layer, so that the same validation is applied when the model is exposed in other ways.