JSF Notes

JSF Life Cycle

 

1. Restore View

Store everything: component, listener, validator in a FaceContext tree under viewRoot. currentView id is used to mark the current view. If not there, created it otherwise, update it.

 

2. apply request value. get value from request and save it to view tree.

If mmediate attribute of component is set, event will propergate to listener , which will be queued.

conversion will happen, if fail will attach new error to component in FaceContext .

 

3. process validation. If any validation errror . error will be display, stop at the stage.

 

4. populate model data. If last step is OK. the bean/model value assocated with view component will be updated.

 

5. invoke the business logic at backend, similar as struts action IMHO.

 

6. JSF render result page to user (I think it go through face-config file to find out next page).

 

JSF support 2 different type of requests and 2 differents type of responses.

1. Face request

2. non-face request

3. face response

4. non-face response

 

 JSF Supports two events types

1. value change event

2. action event.

 

Key points

Long life scope object can not refer to short life object, as reference might points to NULL

 

 JSF Command button

• Attribute: commandName will be sent to even listener.it should only be used to process UI Changes, that dont result in page being loaded.
• Attribute: action will be sent o NavigationHandler
• Attribute: actionRef - action to process...

 Action Listener/ value change listener

you should not create ActionListener to handle event that results associated with navigation.

 

Navigation

1. UICommand defines the outcome.

2. UICommand actionRef will return the outcome.

Then configure file contains the rules for navigation.

 

Common navigation outcome 

1. sucess

2. error

3. logon

4. no results

 

Confusing listener??? have a look at this article

http://onjava.com/pub/a/onjava/excerpt/JSF_chap8/index.html?page=3