public abstract class ViewDeclarationLanguage extends Object
The contract that a view declaration language must implement to interact with the JSF runtime. An implementation of this class must be thread-safe.
Instances of this class are application scoped and must be
obtained from the ViewDeclarationLanguageFactory
.
Modifier and Type | Field and Description |
---|---|
static String |
FACELETS_VIEW_DECLARATION_LANGUAGE_ID
Identifier for the Facelets view declaration language. |
static String |
JSP_VIEW_DECLARATION_LANGUAGE_ID
Identifier for the JSP view declaration language. |
Constructor and Description |
---|
ViewDeclarationLanguage() |
Modifier and Type | Method and Description |
---|---|
abstract void |
buildView(FacesContext context,
UIViewRoot root)
Take any actions specific to
this VDL implementation to cause the argument
|
List<String> |
calculateResourceLibraryContracts(FacesContext context,
String viewId)
Return the list of resource library
contracts that will be made available for use in the view
specified by the argument |
UIComponent |
createComponent(FacesContext context,
String taglibURI,
String tagName,
Map<String,Object> attributes)
Create a component given a
|
abstract UIViewRoot |
createView(FacesContext context,
String viewId)
Create
a |
abstract BeanInfo |
getComponentMetadata(FacesContext context,
Resource componentResource)
Return a reference to the component
metadata for the composite component represented by the argument
|
String |
getId()
Returns a non-null String that can be used to identify this view declaration language. |
abstract Resource |
getScriptComponentResource(FacesContext context,
Resource componentResource)
Take implementation specific action
to discover a |
abstract StateManagementStrategy |
getStateManagementStrategy(FacesContext context,
String viewId)
For implementations that want to
control the implementation of state saving and restoring, the
|
abstract ViewMetadata |
getViewMetadata(FacesContext context,
String viewId)
Return a reference to the view
metadata for the view represented by the argument
|
abstract void |
renderView(FacesContext context,
UIViewRoot view)
Render a view rooted at
argument |
abstract UIViewRoot |
restoreView(FacesContext context,
String viewId)
Restore a |
void |
retargetAttachedObjects(FacesContext context,
UIComponent topLevelComponent,
List<AttachedObjectHandler> handlers)
Assuming the component
metadata for argument |
void |
retargetMethodExpressions(FacesContext context,
UIComponent topLevelComponent)
Assuming the component metadata for
argument |
boolean |
viewExists(FacesContext context,
String viewId)
Tests whether a physical resource corresponding to the specified viewId exists. |
public static final String JSP_VIEW_DECLARATION_LANGUAGE_ID
Identifier for the JSP view declaration language.
public static final String FACELETS_VIEW_DECLARATION_LANGUAGE_ID
Identifier for the Facelets view declaration language.
public abstract BeanInfo getComponentMetadata(FacesContext context, Resource componentResource)
Return a reference to the component
metadata for the composite component represented by the argument
componentResource
, or null
if the
metadata cannot be found. See section JSF.7.7.2 for the
specification of the default implementation. JSP implementations
must throw UnsupportedOperationException
.
context
- The FacesContext
for this request.componentResource
- The Resource
that represents the component.NullPointerException
- if any of the arguments are
null
.FacesException
- if there is an error in
obtaining the metadataUnsupportedOperationException
- if this is a JSP VDL
implementation.public abstract ViewMetadata getViewMetadata(FacesContext context, String viewId)
Return a reference to the view
metadata for the view represented by the argument
viewId
, or null
if the metadata cannot
be found. See section JSF.7.7.2 for the specification of the
default implementation. Facelets for JSF 2 implementation must
return non-null
. JSP implementations must return
null
.
context
- The FacesContext
for this request.viewId
- the view id from whith to extract the metadataNullPointerException
- if any of the arguments are
null
.FacesException
- if there is an error in
obtaining the metadatapublic abstract Resource getScriptComponentResource(FacesContext context, Resource componentResource)
Take implementation specific action
to discover a Resource
given the argument
componentResource
. See section JSF.7.7.2 for the
specification of the default implementation. JSP implementations
must throw UnsupportedOperationException
.
context
- The FacesContext
for this request.componentResource
- The Resource
that represents the component.NullPointerException
- if any of the arguments are
null
.FacesException
- if there is an error in
obtaining the script component resourceUnsupportedOperationException
- if this is a JSP VDL
implementation.public abstract UIViewRoot createView(FacesContext context, String viewId)
Create
a UIViewRoot
from the VDL contained in the artifact referenced by the argument
viewId
. See section JSF.7.7.2 for the specification of
the default implementation.
context
- the FacesContext
for this request.viewId
- the identifier of an artifact that contains the VDL
syntax that describes this view.NullPointerException
- if any of the arguments are
null
public UIComponent createComponent(FacesContext context, String taglibURI, String tagName, Map<String,Object> attributes)
Create a component given a
ViewDeclarationLanguage
specific
tag library URI and tag name. The runtime must support this method operating
for the Facelets VDL.
Other kinds of ViewDeclarationLanguage
may be supported but are not
required to be supported. For backward compatibility
with decorated ViewDeclrationLanguage
implementations that do
not override this method, a default implementation is provided that returns
null
. However, any implementation that is compliant with the
version of the specification in which this method was introduced must
implement this method.
context
- the FacesContext
for this requesttaglibURI
- the fully qualified tag library URI that contains the componenttagName
- the name of the tag within that library that exposes the componentattributes
- any name=value pairs that would otherwise have been
given on the markup that would cause the creation of this component or
null
if no attributes need be given.NullPointerException
- if context
, taglibURI
, or
tagName
are null
public abstract UIViewRoot restoreView(FacesContext context, String viewId)
Restore a UIViewRoot
from a previously created view. See section JSF.7.7.2 for the
specification of the default implementation.
context
- the FacesContext
for this request.viewId
- the identifier for a previously rendered view.NullPointerException
- if any of the arguments are
null
public void retargetAttachedObjects(FacesContext context, UIComponent topLevelComponent, List<AttachedObjectHandler> handlers)
Assuming the component
metadata for argument topLevelComponent
has been
made available by an earlier call to getComponentMetadata(javax.faces.context.FacesContext, javax.faces.application.Resource)
, leverage the
component metadata for the purpose of re-targeting attached
objects from the top level composite component to the individual
AttachedObjectTarget
instances inside the composite
component. This method must be called by the ViewDeclarationLanguage
implementation when creating the
UIComponent
tree when a composite component usage is
encountered.
An algorithm semantically equivalent to the following must be implemented.
Obtain the metadata for the composite component.
Currently this entails getting the value of the UIComponent.BEANINFO_KEY
component attribute, which will be
an instance of BeanInfo
. If the metadata cannot
be found, log an error message and return.
Get the BeanDescriptor
from the
BeanInfo
.
Get the value of the AttachedObjectTarget.ATTACHED_OBJECT_TARGETS_KEY
from the
BeanDescriptor
's getValue()
method.
This will be a List<
. Let this be
targetList.AttachedObjectTarget
>
For each curHandler entry in the argument
handlers
Let forAttributeValue be the return from
AttachedObjectHandler.getFor()
.
For each curTarget entry in targetList, the first of the following items that causes a match will take this action:
For each UIComponent
in the
list returned from curTarget.getTargets(), call
curHandler.applyAttachedObject(),
passing the FacesContext
and the
UIComponent
.
and cause this inner loop to terminate.
If curHandler is an instance of ActionSource2AttachedObjectHandler
and curTarget is an
instance of ActionSource2AttachedObjectTarget
, and
curTarget.getName() is equal to curTargetName,
consider it a match.
If curHandler is an instance of EditableValueHolderAttachedObjectHandler
and curTarget
is an instance of EditableValueHolderAttachedObjectTarget
,
and
curTarget.getName() is equal to curTargetName,
consider it a match.
If curHandler
is an instance of ValueHolderAttachedObjectHandler
and
curTarget is an instance of ValueHolderAttachedObjectTarget
, and curTarget.getName()
is equal to curTargetName, consider it a match.
If curHandler is an instance of BehaviorHolderAttachedObjectHandler
and curTarget is an
instance of BehaviorHolderAttachedObjectTarget
, and either
of the following conditions are true,
null
and is equal to curTargetName.null
and
curTarget.isDefaultEvent() is true
.consider it a match.
The implementation must support retargeting attached objects from the top level compsite component to targets that are composite and non-composite components.
An implementation is provided that will throw
UnsupportedOperationException
. A Faces implementation
compliant with version 2.0 and beyond of the specification must
override this method.
context
- the FacesContext for this request.topLevelComponent
- The UIComponent in the view to which the
attached objects must be attached. This UIComponent must have
its component metadata already associated and available from via
the JavaBeans API.NullPointerException
- if any of the arguments are
null
.public void retargetMethodExpressions(FacesContext context, UIComponent topLevelComponent)
Assuming the component metadata for
argument topLevelComponent
has been made available
by an earlier call to getComponentMetadata(javax.faces.context.FacesContext, javax.faces.application.Resource)
, leverage the
component metadata for the purpose of re-targeting any method
expressions from the top level component to the appropriate inner
component. For each attribute that is a
MethodExpression
(as indicated by the presence of a
"method-signature
" attribute and the absence of a
"type
" attribute), the following action must be
taken:
Get the value of the targets attribute. If the
value is a ValueExpression
evaluate it. If there is
no targets attribute, let the name of the metadata
element be the evaluated value of the targets
attribute.
Interpret targets as a space (not tab) separated list of ids. For each entry in the list:
Find the inner component of the topLevelComponent with the id equal to the current list entry. For discussion, this component is called target. If not found, log and error and continue to the next attribute.
For discussion the declared name of the attribute is called name.
In the attributes map of the
topLevelComponent, look up the entry under the key
name. Assume the result is a
ValueExpression
. For discussion, this is
attributeValueExpression. If not found, log an error
and continue to the next attribute.
If name is equal to the string "action", or
"actionListener" without the quotes, assume target is
an ActionSource2
.
If name is equal to the string "validator", or
"valueChangeListener" without the quotes, assume
target is an EditableValueHolder
.
Call getExpressionString()
on the
attributeValueExpression and use that string to
create a MethodExpression
of the appropriate
signature for name.
If name is not equal to any of the previously
listed strings, call getExpressionString()
on the
attributeValueExpression and use that string to
create a MethodExpression
where the signature is
created based on the value of the
"method-signature
" attribute of the
<composite:attribute />
tag.
Let the resultant MethodExpression
be
called attributeMethodExpression for discussion.
If name is equal to the string "action"
without the quotes, call ActionSource2.setActionExpression(javax.el.MethodExpression)
on
target, passing attributeMethodExpression.
If name is equal to the string
"actionListener" without the quotes, call ActionSource.addActionListener(javax.faces.event.ActionListener)
on
target, passing attributeMethodExpression
wrapped in a MethodExpressionActionListener
.
If name is equal to the string
"validator" without the quotes, call EditableValueHolder.addValidator(javax.faces.validator.Validator)
on target,
passing attributeMethodExpression wrapped in a MethodExpressionValidator
.
If name is equal to the string
"valueChangeListener" without the quotes, call EditableValueHolder.addValueChangeListener(javax.faces.event.ValueChangeListener)
on
target, passing attributeMethodExpression wrapped in a
MethodExpressionValueChangeListener
.
Otherwise, assume that the MethodExpression
should be placed in the components attribute set. The runtme
must create the MethodExpression
instance based on
the value of the "method-signature
"
attribute.
An implementation is provided that will throw
UnsupportedOperationException
. A Faces implementation
compliant with version 2.0 and beyond of the specification must
override this method.
context
- the FacesContext for this request.topLevelComponent
- The UIComponent in the view to which the
attached objects must be attached. This UIComponent must have
its component metadata already associated and available from via
the JavaBeans API.NullPointerException
- if context
or topLevelComponent
is null
.public List<String> calculateResourceLibraryContracts(FacesContext context, String viewId)
Return the list of resource library
contracts that will be made available for use in the view
specified by the argument viewId
. If no match is found,
return an empty list. See section JSF.7.7.2 for the
specification of the default implementation. For backward
compatibility with prior implementations, an implementation is
provided that returns null
, but any implementation
compliant with the version of the specification in which this
method was introduced must implement it as specified in
JSF.7.7.2.
context
- the FacesContext
for this requestviewId
- the view id for which the applicable resource library
contracts should be calculated.public abstract void buildView(FacesContext context, UIViewRoot root) throws IOException
Take any actions specific to
this VDL implementation to cause the argument
UIViewRoot
which must have been created via a call
to createView(javax.faces.context.FacesContext, java.lang.String)
, to be populated with children.
The Facelets implementation must insure that markup comprising
the view must be executed, with the UIComponent
instances in the view being
encountered in the same depth-first order as in other lifecycle
methods defined on UIComponent
, and added to the
view (but not rendered) during the traversal. The runtime must
guarantee that the view must be fully populated before any of the
following happen.
The PhaseListener.afterPhase(javax.faces.event.PhaseEvent)
method of any PhaseListener
s attached to the
application is called
The UIViewRoot
phase
listener installed via UIViewRoot.setAfterPhaseListener(javax.el.MethodExpression)
or UIViewRoot.addPhaseListener(javax.faces.event.PhaseListener)
are called.
If the root
is
already populated with children, the view must still be re-built,
but care must be taken to ensure that the existing components are
correctly paired up with their VDL counterparts in the VDL page.
Also, any system events that would normally be generated during
the adding or removing of components from the view must be
temporarily disabled during the creation of the view and then
re-enabled when the view has been built.
context
- the FacesContext
for this requestroot
- the UIViewRoot
to populate with children
using techniques specific to this VDL implementation.IOException
public abstract void renderView(FacesContext context, UIViewRoot view) throws IOException
Render a view rooted at
argumentview
. See section JSF.7.7.2 for the
specification of the default implementation.
context
- the FacesContext
for this request.view
- the UIViewRoot
from an early call to
createView(javax.faces.context.FacesContext, java.lang.String)
or restoreView(javax.faces.context.FacesContext, java.lang.String)
.NullPointerException
- if any of the arguments are
null
IOException
public abstract StateManagementStrategy getStateManagementStrategy(FacesContext context, String viewId)
For implementations that want to
control the implementation of state saving and restoring, the
StateManagementStrategy
allows them to do so. Returning
null
indicates that the implementation wishes the
runtime to handle the state saving and restoring.
Implementations that provide the VDL for Facelets for JSF 2.0 and
later must return non-null
from this method.
public boolean viewExists(FacesContext context, String viewId)
Tests whether a physical resource corresponding to the specified viewId exists.
The default implementation uses
ResourceHandler.createViewResource(javax.faces.context.FacesContext, java.lang.String)
to locate the physical resource.
context
- The FacesContext
for this request.viewId
- the view id to testpublic String getId()
Returns a non-null String that can be used to identify this view declaration language.
The default implementation returns the fully qualified class name of the view declaration language implementation. Subclasses may override to provide a more meaningful id.
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