Every kind of markup element in Facelets
VDL that has attributes that need to take action on a JSF Java API
artifact is associated with an instance of this class. This class is
an abstraction to enable a rule based method for directing how
different kinds of elements take different kinds of actions in the
JSF Java API. For example, consider this markup:
<h:inputText value="#{user.userid}"
valueChangeListener="#{user.newUserId}" />
This markup element corresponds to an instance of HtmlInputText
in the view.
HtmlImputText
has a number of attributes that are to be
exposed to the page author. HtmlInputText
also
implements EditableValueHolder
, which
extends ValueHolder
. Each of these
interfaces also expose a number of attributes to the page author.
Facelets employes the strategy pattern to allow the manner in
which all possible attributes are handled based on the nature of the
JSF Java API artifact associated with the markup element.
Subclasses override the createMetaRuleset(java.lang.Class)
method to
return a MetaRuleset
instance encapsulating all the strategies
for all the attributes that make sense for this particular markup
element. The runtime calls the setAttributes(FaceletContext, Object)
method to cause those rules to be executed and applied.