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This is the master POM file for Oracle's Implementation of the JSF 2.3 Specification.
There is a newer version: 2.3-pfd
/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
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 * Copyright (c) 1997-2011 Oracle and/or its affiliates. All rights reserved.
 *
 * The contents of this file are subject to the terms of either the GNU
 * General Public License Version 2 only ("GPL") or the Common Development
 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License.  You can
 * obtain a copy of the License at
 * https://glassfish.dev.java.net/public/CDDL+GPL_1_1.html
 * or packager/legal/LICENSE.txt.  See the License for the specific
 * language governing permissions and limitations under the License.
 *
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 * file and include the License file at packager/legal/LICENSE.txt.
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 * GPL Classpath Exception:
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 * exception as provided by Oracle in the GPL Version 2 section of the License
 * file that accompanied this code.
 *
 * Modifications:
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 * enclosed by brackets [] replaced by your own identifying information:
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 */

package javax.faces.event;

import javax.faces.component.UIComponent;
import javax.faces.context.FacesContext;

/**
 *
 * 
 * ComponentSystemEvent is
 * the base class for {@link SystemEvent}s that are specific to a {@link
 * UIComponent} instance.
 *
 * @since 2.0
 */
public abstract class ComponentSystemEvent extends SystemEvent {

    private static final long serialVersionUID = -4726746661822507506L;

    
    // ------------------------------------------------------------ Constructors


    /**
     * Pass the argument
     * component to the superclass constructor.

     * @param component the UIComponent reference to be
     * passed to the superclass constructor.
     *
     * @throws IllegalArgumentException if the argument is null.
     * 
     * @since 2.0
     */
    public ComponentSystemEvent(UIComponent component) {
        super(component);
    }

    /**
     * Return true if the argument
     * {@link FacesListener} is an instance of the appropriate listener class that this event
     * supports.  The default implementation returns true if the listener
     * is a {@link ComponentSystemEventListener} or if super.isAppropriateListener()
     * returns true.
     *
     * @param listener {@link FacesListener} to evaluate
     * @since 2.2
     */
    @Override
    public boolean isAppropriateListener(FacesListener listener) {
        boolean result = (listener instanceof ComponentSystemEventListener);
        if (!result) {
            result = super.isAppropriateListener(listener);
        }
        return result;
    }

    /**
     * Before calling the corresponding method
     * on the superclass, verify that there is a current component so
     * that EL expressions that start with #{component} or #{cc} operate
     * as expected.
     *
     * @param listener {@link FacesListener} to evaluate
     * @since 2.2
     */
    @Override
    public void processListener(FacesListener listener) {
        UIComponent c = getComponent();
        UIComponent cFromStack;
        boolean didPush = false;
        FacesContext context = FacesContext.getCurrentInstance();
        cFromStack = UIComponent.getCurrentComponent(context);
        if (null == cFromStack) {
            didPush = true;
            c.pushComponentToEL(context, null);
        }
        try {
            if (listener instanceof SystemEventListener) {
                super.processListener(listener);
            } else if (listener instanceof ComponentSystemEventListener) {
                ((ComponentSystemEventListener)listener).processEvent(this);
            }
        } finally {
            if (didPush) {
                c.popComponentFromEL(context);
            }
        }
    }
    
    

    // -------------------------------------------------------------- Properties


    /**
     * the source {@link UIComponent} that sent this event.
     * 
     * @since 2.0
     */
    public UIComponent getComponent() {

        return ((UIComponent) getSource());

    }    

}