jakarta.faces.event.SystemEvent Maven / Gradle / Ivy
/*
* 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.event;
import java.util.EventObject;
import jakarta.faces.context.FacesContext;
/**
*
* SystemEvent is the base class for non-application
* specific events that can be fired by arbitrary objects.
*
*
* @since 2.0
*/
public abstract class SystemEvent extends EventObject {
private static final long serialVersionUID = 2696415667461888462L;
/**
*
* Stores the Faces context.
*
*/
private transient FacesContext facesContext;
// ------------------------------------------------------------ Constructors
/**
*
* Pass the argument source to the superclass constructor.
*
*
* @param source the source reference to be passed to the superclass constructor.
*
* @throws IllegalArgumentException if the argument is null.
*/
public SystemEvent(Object source) {
super(source);
}
/**
*
* Pass the argument source to the superclass constructor.
*
*
* @param facesContext the Faces context.
* @param source the source reference to be passed to the superclass constructor.
*
* @throws IllegalArgumentException if the argument is null.
*/
public SystemEvent(FacesContext facesContext, Object source) {
super(source);
this.facesContext = facesContext;
}
// ---------------------------------------------------------- Public Methods
/**
*
* Get the Faces context.
*
*
*
* If the constructor was passed a FacesContext we return it, otherwise we call FacesContext.getCurrentInstance() and
* return it.
*
*
* @return the Faces context.
* @since 2.3
*/
public FacesContext getFacesContext() {
if (facesContext == null) {
facesContext = FacesContext.getCurrentInstance();
}
return facesContext;
}
/**
*
* Return true if this {@link FacesListener} is an instance of a
* the appropriate listener class that this event supports. The default implementation
* returns true if the listener is a {@link ComponentSystemEventListener}.
*
*
* @param listener {@link FacesListener} to evaluate
*
* @return the result as specified above
*/
public boolean isAppropriateListener(FacesListener listener) {
return listener instanceof SystemEventListener;
}
/**
*
* Broadcast this event instance to the specified {@link FacesListener}, by whatever mechanism is appropriate.
* Typically, this will be accomplished by calling an event processing method, and passing this instance as a parameter.
*
*
* @param listener {@link FacesListener} to send this {@link FacesEvent} to
*
* @throws AbortProcessingException Signal the Jakarta Server Faces implementation that no further processing on the
* current event should be performed
*/
public void processListener(FacesListener listener) {
((SystemEventListener) listener).processEvent(this);
}
}