Skip to content

JSF Life Cycle

The JSF (JavaServer Faces) life cycle consists of a series of phases that process a request and generate a response, typically for web applications. The life cycle begins when a user submits a request (e.g., by clicking a button or link) and ends when the response is rendered to the user. The JSF life cycle is divided into the following phases:

1. Restore View Phase

  • Description: In this initial phase, the JSF framework restores or creates the view. It rebuilds the component tree for the UI based on the incoming request. If it's an initial request, it creates a new view; otherwise, it restores the existing one.
  • Purpose: The UI components and associated event handlers and validators are wired up during this phase.

2. Apply Request Values Phase

  • Description: During this phase, JSF retrieves the form data or parameters from the request and applies them to the corresponding UI components in the component tree.
  • Purpose: The submitted data from the user's request is captured, and each component's value is updated with the request parameter.

3. Process Validations Phase

  • Description: Validators are executed during this phase to ensure the data entered by the user is correct. For example, the data might be checked for type constraints, format, or length.
  • Purpose: To validate the input data for correctness. If validation fails, the process jumps to the Render Response phase to display error messages.

4. Update Model Values Phase

  • Description: In this phase, the values of the validated UI components are used to update the corresponding properties (setter methods) of the managed beans.
  • Purpose: To update the model (managed beans) with the new values submitted by the user.

5. Invoke Application Phase

  • Description: This is where the business logic is executed. If the request includes an action (such as a button click), the corresponding action method on the managed bean is invoked.
  • Purpose: To execute business logic (e.g., interacting with a database or other backend systems).

6. Render Response Phase

  • Description: In the final phase, JSF renders the view back to the client. If it's an initial request, it generates the HTML or other markup for the view. If there were validation errors, this phase displays the validation messages.
  • Purpose: To generate and send the response (e.g., HTML) back to the user.

Summary of the JSF Life Cycle Phases:

  1. Restore View
  2. Apply Request Values
  3. Process Validations
  4. Update Model Values
  5. Invoke Application
  6. Render Response

This structured life cycle ensures smooth processing of requests and rendering of views in JSF-based web applications.