public abstract class MetaRule extends Object
The root class of the abstraction that
dictates how attributes on a markup element in a Facelets VDL page
are wired to the JSF API object instance associated with that
element. The single method on this interface, applyRule(java.lang.String, javax.faces.view.facelets.TagAttribute, javax.faces.view.facelets.MetadataTarget)
,
returns an encapsulation of the behavior that actually does the work
of handling the attribute and its value. There are implementations of
specific concrete subclasses of this class for all the basic kinds of
elements that appear in Facelets VDL pages: components,
non-components, and attached objects.
For example, consider this markup:
<h:inputText value="#{user.userid}"
valueChangeListener="#{user.newUserId}" />
Two MetaRule
instances are involved in this example.
The first has
an applyRule()
method that returns a Metadata
instance that, when its applyMetada()
method is called,
dictates how the "value" attribute is processed: calling UIComponent.setValueExpression(java.lang.String, javax.el.ValueExpression)
on the
UIComponent
instance associated with the
<h:inputText>
element.
The second has an applyRule()
method that returns
a Metadata
instance that, when its
applyMetadata()
method is called, dictates how the
"valueChangeListener" attribute is processed: calling EditableValueHolder.addValueChangeListener(javax.faces.event.ValueChangeListener)
.
Constructor and Description |
---|
MetaRule() |
Modifier and Type | Method and Description |
---|---|
abstract Metadata |
applyRule(String name,
TagAttribute attribute,
MetadataTarget meta)
Return an abstraction that takes
appropriate action given the kind of rule represented by the
argument |
public abstract Metadata applyRule(String name, TagAttribute attribute, MetadataTarget meta)
Return an abstraction that takes
appropriate action given the kind of rule represented by the
argument name
, in the context of this particular
concrete subclass of MetaRule
. The abstraction must
encapsulate the value from the argument
attribute
.
name
- the name for this rule. This will generally be the
name of a tag attribute in the VDL.attribute
- the name/value pair for this attribute on this
particular instance of an element in the page.meta
- the MetadataTarged
that can be used to
discern what kind of action to encapsulate within the abstraction
to be returned.Copyright © 2012 JBoss by Red Hat. All Rights Reserved.