ADF Faces Life Cycle Extension
The framework can support validation checking and other traditional server-side functionality, without a round trip to the database server. Do not make this your only validation point in the application. Including database validation prevents applications that circumvent the client (SQL*Plus or procedures) from corrupting your data.
The ADF life cycle prepares and updates the data model, validates the data in the model layer, and executes methods on the business layer. The ADF life cycle uses the binding container to make data available for easy referencing by the page during the current page request.
The combined JSF and ADF life cycle is only one sequence within a larger sequence of events that happens when an HTTP request arrives at the application server until the page is returned to the client. This overall sequence of events can be called the Web page life cycle.