javax.faces.component

Class UIViewAction

java.lang.Object

javax.faces.component.UIComponent

javax.faces.component.UIComponentBase

javax.faces.component.UIViewAction

All Implemented Interfaces:

EventListener, ActionSource, ActionSource2, PartialStateHolder, StateHolder, TransientStateHolder, ComponentSystemEventListener, FacesListener, SystemEventListenerHolder

public class UIViewAction
extends UIComponentBase
implements ActionSource2

UIViewAction represents a method invocation that occurs during the request processing lifecycle, usually in response to an initial request, as opposed to a postback.

The ViewDeclarationLanguage implementation must cause an instance of this component to be placed in the view for each occurrence of an <f:viewAction /> element placed inside of an <f:metadata /> element. The user must place <f:metadata /> as a direct child of the UIViewRoot.

Because this class implements ActionSource2, any actions that one would normally take on a component that implements ActionSource2, such as UICommand, are valid for instances of this class. Instances of this class participate in the regular JSF lifecycle, including on Ajax requests.

The purpose of this component is to provide a light-weight front-controller solution for executing code upon the loading of a JSF view to support the integration of system services, content retrieval, view management, and navigation. This functionality is especially useful for non-faces (initial) requests.

The most common use case for this component is to take actions necessary for a particular view, often with the help of one or more UIViewParameters.

The NavigationHandler is consulted after the action is invoked to carry out the navigation case that matches the action signature and outcome. If a navigation case is matched that causes the new viewId to be different from the current viewId, the runtime must force a redirect to that matched navigation case with different viewId, regardless of whether or not the matched navigation case with different viewId called for a redirect. If the response is marked complete by the action, the lifecycle advances appropriately.

It's important to note that the full component tree is not built before the UIViewAction components are processed on an non-faces (initial) request. Rather, the component tree only contains the ViewMetadata, an important part of the optimization of this component and what sets it apart from a PreRenderViewEvent listener.

Since:

2.2

Field Summary

Fields

Modifier and Type	Field and Description
static String	COMPONENT_FAMILY The standard component family for this component.
static String	COMPONENT_TYPE The standard component type for this component.

Fields inherited from class javax.faces.component.UIComponent

ATTRS_WITH_DECLARED_DEFAULT_VALUES, BEANINFO_KEY, bindings, COMPOSITE_COMPONENT_TYPE_KEY, COMPOSITE_FACET_NAME, CURRENT_COMPONENT, CURRENT_COMPOSITE_COMPONENT, FACETS_KEY, HONOR_CURRENT_COMPONENT_ATTRIBUTES_PARAM_NAME, VIEW_LOCATION_KEY

Constructor Summary

Constructors

Constructor and Description
UIViewAction() Create a new UIViewAction instance with default property values.

Method Summary

Methods

Modifier and Type	Method and Description
void	addActionListener(ActionListener listener) Add a new ActionListener to the set of listeners interested in being notified when ActionEvents occur.
void	broadcast(FacesEvent event) Enable the method invocation specified by this component instance to return a value that performs navigation, similar in spirit to UICommand.broadcast(javax.faces.event.FacesEvent).
void	decode(FacesContext context) Override behavior from the superclass to queue an ActionEvent that may result in the invocation of the action or any actionListeners that may be associated with this instance.
MethodBinding	getAction() Deprecated.
MethodExpression	getActionExpression() Return the MethodExpression pointing at the application action to be invoked, if this UIComponent is activated by the user, during the Apply Request Values or Invoke Application phase of the request processing lifecycle, depending on the value of the immediate property.
MethodBinding	getActionListener() Deprecated.
ActionListener[]	getActionListeners() Return the set of registered ActionListeners for this ActionSource instance.
String	getFamily() Return the identifier of the component family to which this component belongs.
String	getPhase() Returns the name of the lifecycle phase in which the action is to be queued.
boolean	isImmediate() If the value of the component's immediate attribute is true, the action will be invoked during the Apply Request Values JSF lifecycle phase.
boolean	isOnPostback() If true this component will operate on postback.
static boolean	isProcessingBroadcast(FacesContext context) Returns true if the current request processing lifecycle is in the midst of processing the broadcast of an event queued during a call to decode(javax.faces.context.FacesContext).
boolean	isRendered() Return true if this component should take the actions specified in the decode(javax.faces.context.FacesContext) method.
void	removeActionListener(ActionListener listener) Remove an existing ActionListener (if any) from the set of listeners interested in being notified when ActionEvents occur.
void	setAction(MethodBinding action) Deprecated.
void	setActionExpression(MethodExpression actionExpression) Set the MethodExpression pointing at the appication action to be invoked, if this UIComponent is activated by the user, during the Apply Request Values or Invoke Application phase of the request processing lifecycle, depending on the value of the immediate property.
void	setActionListener(MethodBinding actionListener) Deprecated.
void	setImmediate(boolean immediate) Set the "immediate execution" flag for this UIComponent.
void	setOnPostback(boolean onPostback) Controls whether or not this component operates on postback.
void	setPhase(String phase) Attempt to set the lifecycle phase in which this instance will queue its ActionEvent.
void	setRendered(boolean condition) Sets the if property of this component.

Methods inherited from class javax.faces.component.UIComponentBase

addClientBehavior, addFacesListener, clearInitialState, encodeBegin, encodeChildren, encodeEnd, findComponent, getAttributes, getChildCount, getChildren, getClientBehaviors, getClientId, getDefaultEventName, getEventNames, getFacesContext, getFacesListeners, getFacet, getFacetCount, getFacets, getFacetsAndChildren, getId, getListenersForEventClass, getParent, getPassThroughAttributes, getRenderer, getRendererType, getRendersChildren, getValueBinding, invokeOnComponent, isTransient, markInitialState, processDecodes, processRestoreState, processSaveState, processUpdates, processValidators, queueEvent, removeFacesListener, restoreAttachedState, restoreState, saveAttachedState, saveState, setId, setParent, setRendererType, setTransient, setValueBinding, subscribeToEvent, unsubscribeFromEvent

Methods inherited from class javax.faces.component.UIComponent

encodeAll, getClientId, getCompositeComponentParent, getContainerClientId, getCurrentComponent, getCurrentCompositeComponent, getNamingContainer, getPassThroughAttributes, getResourceBundleMap, getStateHelper, getStateHelper, getTransientStateHelper, getTransientStateHelper, getValueExpression, initialStateMarked, isCompositeComponent, isInView, isVisitable, popComponentFromEL, processEvent, pushComponentToEL, restoreTransientState, saveTransientState, setInView, setValueExpression, visitTree

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

COMPONENT_TYPE

public static final String COMPONENT_TYPE

The standard component type for this component.

See Also:

Constant Field Values

COMPONENT_FAMILY

public static final String COMPONENT_FAMILY

The standard component family for this component.

See Also:

Constant Field Values

Constructor Detail

UIViewAction

public UIViewAction()

Create a new UIViewAction instance with default property values.

Method Detail

getFamily

public String getFamily()

Description copied from class: UIComponent

Return the identifier of the component family to which this component belongs. This identifier, in conjunction with the value of the rendererType property, may be used to select the appropriate Renderer for this component instance.

Specified by:

getFamily in class UIComponent

getAction

@Deprecated
public MethodBinding getAction()

Deprecated.

If the implementing class also implements ActionSource2, the implementation of this method must call through to ActionSource2.getActionExpression() and examine the result. If the result came from a previous call to ActionSource.setAction(javax.faces.el.MethodBinding), extract the MethodBinding from it and return it. Otherwise, wrap the returned MethodExpression in a MethodBinding implementation, and return it.

If the implementing class does not implement ActionSource2, return the MethodBindingpointing at the application action to be invoked, if this UIComponent is activated by the user, during the Apply Request Values or Invoke Application phase of the request processing lifecycle, depending on the value of the immediate property.

Specified by:

getAction in interface ActionSource

Since:

2.2

setAction

@Deprecated
public void setAction(MethodBinding action)

Deprecated.

If the implementing class also implements ActionSource2, the implementation of this method must wrap the argument action in a class that implements MethodExpression and call through to ActionSource2.setActionExpression(javax.el.MethodExpression), passing the wrapped action.

If the implementing class does not implement ActionSource2, set the MethodBinding pointing at the appication action to be invoked, if this UIComponent is activated by the user, during the Apply Request Values or Invoke Application phase of the request processing lifecycle, depending on the value of the immediate property.

Any method referenced by such an expression must be public, with a return type of String, and accept no parameters.

Specified by:

setAction in interface ActionSource

Parameters:

action - The new MethodBinding expression

Since:

2.2

getActionListener

@Deprecated
public MethodBinding getActionListener()

Deprecated.

If ActionSource.setActionListener(javax.faces.el.MethodBinding) was not previously called for this instance, this method must return null. If it was called, this method must return the exact MethodBinding instance that was passed to ActionSource.setActionListener(javax.faces.el.MethodBinding).

The method to be invoked, if this UIComponent is activated by the user, will be called during the Apply Request Values or Invoke Application phase of the request processing lifecycle, depending upon the value of the immediate property.

Specified by:

getActionListener in interface ActionSource

Since:

2.2

setActionListener

@Deprecated
public void setActionListener(MethodBinding actionListener)

Deprecated.

Wrap the argument actionListener in an implementation of ActionListener and store it in the internal data structure that backs the ActionSource.getActionListeners() method, taking care to over-write any instance that was stored by a previous call to setActionListener.

Any method referenced by such an expression must be public, with a return type of void, and accept a single parameter of type ActionEvent.

Specified by:

setActionListener in interface ActionSource

Parameters:

actionListener - The new method binding expression

Since:

2.2

isImmediate

public boolean isImmediate()

If the value of the component's immediate attribute is true, the action will be invoked during the Apply Request Values JSF lifecycle phase. Otherwise, the action will be invoked during the Invoke Application phase, the default behavior. The phase can be set explicitly in the phase attribute, which takes precedence over the immediate attribute.

Specified by:

isImmediate in interface ActionSource

Since:

2.2

setImmediate

public void setImmediate(boolean immediate)

Set the "immediate execution" flag for this UIComponent.

Specified by:

setImmediate in interface ActionSource

Parameters:

immediate - The new immediate execution flag

Since:

2.2

getPhase

public String getPhase()

Returns the name of the lifecycle phase in which the action is to be queued.

Since:

2.2

setPhase

public void setPhase(String phase)

Attempt to set the lifecycle phase in which this instance will queue its ActionEvent. Pass the argument phase to PhaseId.phaseIdValueOf(java.lang.String). If the result is not one of the following values, FacesException must be thrown.

• PhaseId.APPLY_REQUEST_VALUES

• PhaseId.PROCESS_VALIDATIONS

• PhaseId.UPDATE_MODEL_VALUES

• PhaseId.INVOKE_APPLICATION

If set, this value takes precedence over the immediate flag.

Since:

2.2

isProcessingBroadcast

public static boolean isProcessingBroadcast(FacesContext context)

Returns true if the current request processing lifecycle is in the midst of processing the broadcast of an event queued during a call to decode(javax.faces.context.FacesContext). The implementation of broadcast(javax.faces.event.FacesEvent) is responsible for ensuring that calls to this method accurately reflect this fact.

Parameters:

context - FacesContext for the current request

Since:

2.2

addActionListener

public void addActionListener(ActionListener listener)

Add a new ActionListener to the set of listeners interested in being notified when ActionEvents occur.

Specified by:

addActionListener in interface ActionSource

Parameters:

listener - The ActionListener to be added

Since:

2.2

getActionListeners

public ActionListener[] getActionListeners()

Return the set of registered ActionListeners for this ActionSource instance. If there are no registered listeners, a zero-length array is returned.

Specified by:

getActionListeners in interface ActionSource

Since:

2.2

removeActionListener

public void removeActionListener(ActionListener listener)

Remove an existing ActionListener (if any) from the set of listeners interested in being notified when ActionEvents occur.

Specified by:

removeActionListener in interface ActionSource

Parameters:

listener - The ActionListener to be removed

Since:

2.2

getActionExpression

public MethodExpression getActionExpression()

Return the MethodExpression pointing at the application action to be invoked, if this UIComponent is activated by the user, during the Apply Request Values or Invoke Application phase of the request processing lifecycle, depending on the value of the immediate property.

Note that it's possible that the returned MethodExpression is just a wrapper around a MethodBinding instance whith was set by a call to ActionSource.setAction(javax.faces.el.MethodBinding). This makes it possible for the default ActionListener to continue to work properly with older components.

Specified by:

getActionExpression in interface ActionSource2

Since:

2.2

setActionExpression

public void setActionExpression(MethodExpression actionExpression)

Set the MethodExpression pointing at the appication action to be invoked, if this UIComponent is activated by the user, during the Apply Request Values or Invoke Application phase of the request processing lifecycle, depending on the value of the immediate property.

Any method referenced by such an expression must be public, with a return type of String, and accept no parameters.

Specified by:

setActionExpression in interface ActionSource2

Parameters:

actionExpression - The new method expression

Since:

2.2

isOnPostback

public boolean isOnPostback()

If true this component will operate on postback.

Since:

2.2

setOnPostback

public void setOnPostback(boolean onPostback)

Controls whether or not this component operates on postback.

Since:

2.2

isRendered

public boolean isRendered()

Return true if this component should take the actions specified in the decode(javax.faces.context.FacesContext) method.

Overrides:

isRendered in class UIComponentBase

Since:

2.2

setRendered

public void setRendered(boolean condition)

Sets the if property of this component.

Overrides:

setRendered in class UIComponentBase

Parameters:

condition - the new value of the property.

Since:

2.2

broadcast

public void broadcast(FacesEvent event)
               throws AbortProcessingException

Enable the method invocation specified by this component instance to return a value that performs navigation, similar in spirit to UICommand.broadcast(javax.faces.event.FacesEvent).

Take no action and return immediately if any of the following conditions are true.

• The response has already been marked as complete.

• The current UIViewRoot is different from the event's source's UIViewRoot.

Save a local reference to the viewId of the current UIViewRoot. For discussion, let this reference be viewIdBeforeAction.

Obtain the ActionListener from the Application. Wrap the current FacesContext in an implementation of FacesContextWrapper that overrides the FacesContext.renderResponse() method such that it takes no action. Set the current FacesContext to be the FacesContextWrapper instance. Make it so a call to isProcessingBroadcast(javax.faces.context.FacesContext) on the current FacesContext will return true. This is necessary because the NavigationHandler will call this method to determine if the navigation is happening as the result of a UIViewAction. Invoke ActionListener.processAction(javax.faces.event.ActionEvent). In a finally block, restore the original FacesContext, make it so a call to isProcessingBroadcast(javax.faces.context.FacesContext) on the current context will return false and discard the wrapper.

If the response has been marked as complete during the invocation of processAction(), take no further action and return. Otherwise, compare viewIdBeforeAction with the viewId of the UIViewRoot on the FacesContext after the invocation of processAction(). If the two viewIds are the same and no more UIViewAction events have been queued by a call to decode(javax.faces.context.FacesContext), call FacesContext.renderResponse() and return. It is possible to detect the case where no more UIViewAction events have been queued because the number of such events queued has been noted in the specification for decode(javax.faces.context.FacesContext). Otherwise, execute the lifecycle on the new UIViewRoot.

Overrides:

broadcast in class UIComponentBase

Parameters:

event - FacesEvent to be broadcast

Throws:

AbortProcessingException - Signal the JavaServer Faces implementation that no further processing on the current event should be performed

IllegalArgumentException - if the implementation class of this FacesEvent is not supported by this component

NullPointerException - if event is null

Since:

2.2

decode

public void decode(FacesContext context)

Override behavior from the superclass to queue an ActionEvent that may result in the invocation of the action or any actionListeners that may be associated with this instance.

Take no action if any of the following conditions are true:

• The current request is a postback and the instance has been configured to not operate on postback. See isOnPostback().

• The condition stated in the if property evaluates to false. See isRendered()

  .

Instantiate an ActionEvent, passing this component instance as the source. Set the phaseId property of the ActionEvent as follows.

• If this component instance has been configured with a specific lifecycle phase with a call to setPhase(java.lang.String) use that as the phaseId

• If the value of the immediate property is true, use PhaseId.APPLY_REQUEST_VALUES.

• Otherwise, use PhaseId.INVOKE_APPLICATION.

Queue the event with a call to UIComponentBase.queueEvent(javax.faces.event.FacesEvent). Keep track of the number of events that are queued in this way on this run through the lifecycle. This information is necessary during processing in broadcast(javax.faces.event.FacesEvent).

Overrides:

decode in class UIComponentBase

Parameters:

context - FacesContext for the request we are processing

Since:

2.2