/* * $Id: TextElementCommon.java,v 1.5 2002/10/02 19:08:03 hamada Exp $ ******************** * * Copyright (c) 2001 Sun Microsystems, Inc.  All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright *    notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright *    notice, this list of conditions and the following disclaimer in *    the documentation and/or other materials provided with the *    distribution. * * 3. The end-user documentation included with the redistribution, *    if any, must include the following acknowledgment: *       "This product includes software developed by the *       Sun Microsystems, Inc. for Project JXTA." *    Alternately, this acknowledgment may appear in the software itself, *    if and wherever such third-party acknowledgments normally appear. * * 4. The names "Sun", "Sun Microsystems, Inc.", "JXTA" and "Project JXTA" must *    not be used to endorse or promote products derived from this *    software without prior written permission. For written *    permission, please contact Project JXTA at http://www.jxta.org. * * 5. Products derived from this software may not be called "JXTA", *    nor may "JXTA" appear in their name, without prior written *    permission of Sun. * * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED.  IN NO EVENT SHALL SUN MICROSYSTEMS OR * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * ==================================================================== * * This software consists of voluntary contributions made by many * individuals on behalf of Project JXTA.  For more * information on Project JXTA, please see * <http://www.jxta.org/>. * * This license is based on the BSD license adopted by the Apache Foundation. ******************** */package net.jxta.impl.document;import java.util.Enumeration;import net.jxta.document.Element;import net.jxta.document.TextElement;/** * This class represent an element of a Text document. This class provides * some common things needed by TextElement instances. * */public abstract class TextElementCommon implements TextElement {        /**     * Add a child element to this element     *     * @param element the element to be added as a child     */    public void appendChild(Element element) {        if( element instanceof TextElement )            ((TextElement) this).appendChild( (TextElement) element );        else            throw new ClassCastException( element.getClass().getName() + " not supported by appendChild." );    }       /**     * Returns an enumeration of the immediate children of this element whose     * name match the specified string.     *     * @param key The key which will be matched against.     * @return enumeration containing all of the children of this element.     */    public Enumeration getChildren(Object key) {        if( key instanceof String )            return ((TextElement) this).getChildren ( (String) key );        else            throw new ClassCastException( key.getClass().getName() + " not supported by getChildren." );    }        /**     * Get the name associated with an element.     *     * @return A string containing the key of this element.     */    public Object getKey() {        return getName();    }        /**     * Get the value (if any) associated with an element.     *     * @return A string containing the value of this element, if any, otherwise null.     */    public Object getValue() {        return getTextValue();    }    }