/*
 * Copyright (c) 1997, 2009, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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 */

package java.beans.beancontext;

import java.util.EventObject;

import java.beans.beancontext.BeanContext;

/**
 * <p>
 * {@code BeanContextEvent} is the abstract root event class
 * for all events emitted
 * from, and pertaining to the semantics of, a {@code BeanContext}.
 * This class introduces a mechanism to allow the propagation of
 * {@code BeanContextEvent} subclasses through a hierarchy of
 * {@code BeanContext}s. The {@code setPropagatedFrom()}
 * and {@code getPropagatedFrom()} methods allow a
 * {@code BeanContext} to identify itself as the source
 * of a propagated event.
 * </p>
 *
 * @author      Laurence P. G. Cable
 * @since       1.2
 * @see         java.beans.beancontext.BeanContext
 */

public abstract class BeanContextEvent extends EventObject {
    private static final long serialVersionUID = 7267998073569045052L;

    /**
     * Contruct a BeanContextEvent
     *
     * @param bc        The BeanContext source
     */
    protected BeanContextEvent(BeanContext bc) {
        super(bc);
    }

    /**
     * Gets the {@code BeanContext} associated with this event.
     * @return the {@code BeanContext} associated with this event.
     */
    public BeanContext getBeanContext() { return (BeanContext)getSource(); }

    /**
     * Sets the {@code BeanContext} from which this event was propagated.
     * @param bc the {@code BeanContext} from which this event
     * was propagated
     */
    public synchronized void setPropagatedFrom(BeanContext bc) {
        propagatedFrom = bc;
    }

    /**
     * Gets the {@code BeanContext} from which this event was propagated.
     * @return the {@code BeanContext} from which this
     * event was propagated
     */
    public synchronized BeanContext getPropagatedFrom() {
        return propagatedFrom;
    }

    /**
     * Reports whether or not this event is
     * propagated from some other {@code BeanContext}.
     * @return {@code true} if propagated, {@code false}
     * if not
     */
    public synchronized boolean isPropagated() {
        return propagatedFrom != null;
    }

    /*
     * fields
     */

    /**
     * The {@code BeanContext} from which this event was propagated
     */
    @SuppressWarnings("serial") // Not statically typed as Serializable
    protected BeanContext propagatedFrom;
}