In this phase the Faces servlet iterates over the component objects in the component tree created during the restore view phase .Each component object checks which request values belongs to it and stores them. (This is done by retrieving from the faces context object)They are retrieved from request parametes , they can also be retrieved from cookies or headers.This phase also adds the events to an event queue when the command button or the link is pressed .Events are also executed at the end of each phase. The event processing can end the execution and skip to the render response phase directly or can also terminate the request processing altogether .
If a component's immediate event handling property is not set to true, the values are just converted. So if the field is bound to an Integer property, the value is converted to an Integer. If the value conversion fails, an error message is generated and queued in the FacesContext, where it will be displayed during the render response phase, along with any validation errors.
If a component's immediate event handling property is set to true, the values are converted to the proper type and validated. The converted value is then stored in the component. If the value conversion or value validation fails, an error message is generated and queued in the FacesContext, where it will be displayed during the render response phase, along with any other validation errors.
Immediate event handling
The immediate event handling property of JSF is used to handle events that normally don't need to validate the entire form
posted by Priyanka