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/*
* Copyright (c) 1997, 2020 Oracle and/or its affiliates. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v. 2.0, which is available at
* http://www.eclipse.org/legal/epl-2.0.
*
* This Source Code may also be made available under the following Secondary
* Licenses when the conditions for such availability set forth in the
* Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
* version 2 with the GNU Classpath Exception, which is available at
* https://www.gnu.org/software/classpath/license.html.
*
* SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
*/
package jakarta.faces.component;
import static jakarta.faces.event.PhaseId.APPLY_REQUEST_VALUES;
import static jakarta.faces.event.PhaseId.INVOKE_APPLICATION;
import jakarta.el.MethodExpression;
import jakarta.faces.application.Application;
import jakarta.faces.context.FacesContext;
import jakarta.faces.event.AbortProcessingException;
import jakarta.faces.event.ActionEvent;
import jakarta.faces.event.ActionListener;
import jakarta.faces.event.FacesEvent;
import jakarta.faces.render.Renderer;
/**
*
* UICommand is a {@link 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 {@link UICommand}, or its corresponding {@link Renderer}, detects that
* this control has been activated, it will queue an {@link 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:
*
* - {@link ActionListener}s, in the order in which they were registered.
*
- The "actionListener" {@link MethodExpression} (which will cover the "actionListener" that was set as a
*
MethodBinding).
* - The default {@link ActionListener}, retrieved from the {@link Application} - and therefore, any attached "action"
* {@link MethodExpression}.
*
*
*
* By default, the rendererType property must be set to "jakarta.faces.Button". This value can
* be changed by calling the setRendererType() method.
*
*/
public class UICommand extends UIComponentBase implements ActionSource {
// ------------------------------------------------------ Manifest Constants
/**
*
* The standard component type for this component.
*
*/
public static final String COMPONENT_TYPE = "jakarta.faces.Command";
/**
*
* The standard component family for this component.
*
*/
public static final String COMPONENT_FAMILY = "jakarta.faces.Command";
/**
* Properties that are tracked by state saving.
*/
enum PropertyKeys {
value, immediate, methodBindingActionListener, actionExpression,
}
// ------------------------------------------------------------ Constructors
/**
*
* Create a new {@link UICommand} instance with default property values.
*
*/
public UICommand() {
super();
setRendererType("jakarta.faces.Button");
}
// -------------------------------------------------------------- Properties
@Override
public String getFamily() {
return COMPONENT_FAMILY;
}
// ------------------------------------------------- ActionSource Properties
/**
*
* The immediate flag.
*
*/
@Override
public boolean isImmediate() {
return (Boolean) getStateHelper().eval(PropertyKeys.immediate, false);
}
@Override
public void setImmediate(boolean immediate) {
getStateHelper().put(PropertyKeys.immediate, immediate);
}
/**
*
* Returns the value property of the UICommand. This is most often rendered as a label.
*
*
* @return The object representing the value of this component.
*/
public Object getValue() {
return getStateHelper().eval(PropertyKeys.value);
}
/**
*
* Sets the value property of the UICommand. This is most often rendered as a label.
*
*
* @param value the new value
*/
public void setValue(Object value) {
getStateHelper().put(PropertyKeys.value, value);
}
// ---------------------------------------------------- ActionSource Methods
@Override
public MethodExpression getActionExpression() {
return (MethodExpression) getStateHelper().get(PropertyKeys.actionExpression);
}
@Override
public void setActionExpression(MethodExpression actionExpression) {
getStateHelper().put(PropertyKeys.actionExpression, actionExpression);
}
/**
* @throws NullPointerException {@inheritDoc}
*/
@Override
public void addActionListener(ActionListener listener) {
addFacesListener(listener);
}
@Override
public ActionListener[] getActionListeners() {
return (ActionListener[]) getFacesListeners(ActionListener.class);
}
/**
* @throws NullPointerException {@inheritDoc}
*/
@Override
public void removeActionListener(ActionListener listener) {
removeFacesListener(listener);
}
// ----------------------------------------------------- UIComponent Methods
/**
*
* In addition to to the default {@link UIComponent#broadcast} processing, pass the {@link ActionEvent} being broadcast
* to the method referenced by actionListener (if any), and to the default {@link ActionListener}
* registered on the {@link jakarta.faces.application.Application}.
*
*
* @param event {@link FacesEvent} to be broadcast
*
* @throws AbortProcessingException Signal the Jakarta Faces implementation that no further processing on the
* current event should be performed
* @throws IllegalArgumentException if the implementation class of this {@link FacesEvent} is not supported by this
* component
* @throws NullPointerException if event is null
*/
@Override
public void broadcast(FacesEvent event) throws AbortProcessingException {
// Perform standard superclass processing (including calling our
// ActionListeners)
super.broadcast(event);
if (event instanceof ActionEvent) {
FacesContext context = event.getFacesContext();
// Invoke the default ActionListener
ActionListener listener = context.getApplication().getActionListener();
if (listener != null) {
listener.processAction((ActionEvent) event);
}
}
}
/**
*
*
* Intercept queueEvent and take the following action. If the event is an {@link ActionEvent},
* obtain the UIComponent instance from the event. If the component is an {@link 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.
*
*
*/
@Override
public void queueEvent(FacesEvent event) {
UIComponent component = event.getComponent();
if (event instanceof ActionEvent && component instanceof ActionSource) {
if (((ActionSource) component).isImmediate()) {
event.setPhaseId(APPLY_REQUEST_VALUES);
} else {
event.setPhaseId(INVOKE_APPLICATION);
}
}
super.queueEvent(event);
}
}