UICommand

java.lang.Object
- jakarta.faces.component.UIComponent
- - jakarta.faces.component.UIComponentBase
  - - jakarta.faces.component.UICommand

All Implemented Interfaces:

ActionSource, ActionSource2, PartialStateHolder, StateHolder, TransientStateHolder, ComponentSystemEventListener, FacesListener, SystemEventListenerHolder, java.util.EventListener

Direct Known Subclasses:

HtmlCommandButton, HtmlCommandLink, HtmlCommandScript
```
public class UICommand
extends UIComponentBase
implements ActionSource2
```
UICommand is a UIComponent that represents a user interface component which, when activated by the user, triggers an application specific "command" or "action". Such a component is typically rendered as a push button, a menu item, or a hyperlink.

When the decode() method of this UICommand, or its corresponding Renderer, detects that this control has been activated, it will queue an ActionEvent. Later on, the broadcast() method will ensure that this event is broadcast to all interested listeners.

Listeners will be invoked in the following order:
1. ActionListeners, in the order in which they were registered.
2. The "actionListener" MethodExpression (which will cover the "actionListener" that was set as a MethodBinding).
3. The default ActionListener, retrieved from the Application - and therefore, any attached "action" MethodExpression.
By default, the rendererType property must be set to "jakarta.faces.Button". This value can be changed by calling the setRendererType() method.

Field Summary

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

Fields inherited from class jakarta.faces.component.UIComponent
ATTRS_WITH_DECLARED_DEFAULT_VALUES, BEANINFO_KEY, bindings, COMPOSITE_COMPONENT_TYPE_KEY, COMPOSITE_FACET_NAME, FACETS_KEY, VIEW_LOCATION_KEY

Constructor Summary

Constructors
Constructor and Description

UICommand()
Create a new UICommand instance with default property values.

Constructors
Constructor and Description
`UICommand()` Create a new `UICommand` instance with default property values.

Method Summary

All Methods Instance Methods Concrete 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 `ActionEvent`s occur.
`void`	`broadcast(FacesEvent event)` In addition to to the default `UIComponent.broadcast(jakarta.faces.event.FacesEvent)` processing, pass the `ActionEvent` being broadcast to the method referenced by `actionListener` (if any), and to the default `ActionListener` registered on the `Application`.
`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.
`ActionListener[]`	`getActionListeners()` Return the set of registered `ActionListener`s for this `ActionSource` instance.
`java.lang.String`	`getFamily()` Return the identifier of the component family to which this component belongs.
`java.lang.Object`	`getValue()` Returns the `value` property of the `UICommand`.
`boolean`	`isImmediate()` The immediate flag.
`void`	`queueEvent(FacesEvent event)` Intercept `queueEvent` and take the following action.
`void`	`removeActionListener(ActionListener listener)` Remove an existing `ActionListener` (if any) from the set of listeners interested in being notified when `ActionEvent`s occur.
`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`	`setImmediate(boolean immediate)` Set the "immediate execution" flag for this `UIComponent`.
`void`	`setValue(java.lang.Object value)` Sets the `value` property of the `UICommand`.

Methods inherited from class jakarta.faces.component.UIComponentBase
addClientBehavior, addFacesListener, clearInitialState, decode, encodeBegin, encodeChildren, encodeEnd, findComponent, getAttributes, getChildCount, getChildren, getClientBehaviors, getClientId, getDefaultEventName, getEventNames, getFacesContext, getFacesListeners, getFacet, getFacetCount, getFacets, getFacetsAndChildren, getId, getListenersForEventClass, getParent, getPassThroughAttributes, getRenderer, getRendererType, getRendersChildren, invokeOnComponent, isRendered, isTransient, markInitialState, processDecodes, processRestoreState, processSaveState, processUpdates, processValidators, removeFacesListener, restoreAttachedState, restoreState, saveAttachedState, saveState, setId, setParent, setRendered, setRendererType, setTransient, subscribeToEvent, unsubscribeFromEvent

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 java.lang.String COMPONENT_TYPE
```
    The standard component type for this component.
    
    See Also:
    
    Constant Field Values
  - COMPONENT_FAMILY
```
public static final java.lang.String COMPONENT_FAMILY
```
    The standard component family for this component.
    
    See Also:
    
    Constant Field Values
- Constructor Detail
  - UICommand
```
public UICommand()
```
    Create a new UICommand instance with default property values.
- Method Detail
  - getFamily
```
public java.lang.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. Note this method should NOT return null
    
    Specified by:
    
    getFamily in class UIComponent
    
    Returns:
    
    the component family (not null).
  - isImmediate
```
public boolean isImmediate()
```
    The immediate flag.
    
    Specified by:
    
    isImmediate in interface ActionSource
    
    Returns:
    
    true if immediate, false otherwise.
  - setImmediate
```
public void setImmediate(boolean immediate)
```
    Description copied from interface: ActionSource
    
    Set the "immediate execution" flag for this UIComponent.
    
    Specified by:
    
    setImmediate in interface ActionSource
    
    Parameters:
    
    immediate - The new immediate execution flag
  - getValue
```
public java.lang.Object getValue()
```
    Returns the value property of the UICommand. This is most often rendered as a label.
    
    Returns:
    
    The object representing the value of this component.
  - setValue
```
public void setValue(java.lang.Object value)
```
    Sets the value property of the UICommand. This is most often rendered as a label.
    
    Parameters:
    
    value - the new value
  - getActionExpression
```
public MethodExpression getActionExpression()
```
    Description copied from interface: ActionSource2
    
    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.
    
    Specified by:
    
    getActionExpression in interface ActionSource2
    
    Returns:
    
    the action expression.
  - setActionExpression
```
public void setActionExpression(MethodExpression actionExpression)
```
    Description copied from interface: ActionSource2
    
    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
  - addActionListener
```
public void addActionListener(ActionListener listener)
```
    Description copied from interface: ActionSource
    
    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
    
    Throws:
    
    java.lang.NullPointerException - if listener is null
  - getActionListeners
```
public ActionListener[] getActionListeners()
```
    Description copied from interface: ActionSource
    
    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
    
    Returns:
    
    the action listeners, or a zero-length array.
  - removeActionListener
```
public void removeActionListener(ActionListener listener)
```
    Description copied from interface: ActionSource
    
    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
    
    Throws:
    
    java.lang.NullPointerException - if listener is null
  - broadcast
```
public void broadcast(FacesEvent event)
               throws AbortProcessingException
```
    In addition to to the default UIComponent.broadcast(jakarta.faces.event.FacesEvent) processing, pass the ActionEvent being broadcast to the method referenced by actionListener (if any), and to the default ActionListener registered on the Application.
    
    Overrides:
    
    broadcast in class UIComponentBase
    
    Parameters:
    
    event - FacesEvent to be broadcast
    
    Throws:
    
    AbortProcessingException - Signal the Jakarta Faces implementation that no further processing on the current event should be performed
    
    java.lang.IllegalArgumentException - if the implementation class of this FacesEvent is not supported by this component
    
    java.lang.NullPointerException - if event is null
  - queueEvent
```
public void queueEvent(FacesEvent event)
```
    Intercept queueEvent and take the following action. If the event is an ActionEvent, obtain the UIComponent instance from the event. If the component is an ActionSource obtain the value of its "immediate" property. If it is true, mark the phaseId for the event to be PhaseId.APPLY_REQUEST_VALUES otherwise, mark the phaseId to be PhaseId.INVOKE_APPLICATION. The event must be passed on to super.queueEvent() before returning from this method.
    
    Overrides:
    
    queueEvent in class UIComponentBase
    
    Parameters:
    
    event - FacesEvent to be queued

Class UICommand

Field Summary

Fields inherited from class jakarta.faces.component.UIComponent

Constructor Summary

Method Summary

Methods inherited from class jakarta.faces.component.UIComponentBase

Methods inherited from class jakarta.faces.component.UIComponent

Methods inherited from class java.lang.Object

Field Detail

COMPONENT_TYPE

COMPONENT_FAMILY

Constructor Detail

UICommand

Method Detail

getFamily

isImmediate

setImmediate

getValue

setValue

getActionExpression

setActionExpression

addActionListener

getActionListeners

removeActionListener

broadcast

queueEvent