/*-- $Id: ElementFilter.java,v 1.20 2007/11/10 05:29:00 jhunter Exp $ Copyright (C) 2000-2007 Jason Hunter & Brett McLaughlin. 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 disclaimer that follows    these conditions in the documentation and/or other materials    provided with the distribution. 3. The name "JDOM" must not be used to endorse or promote products    derived from this software without prior written permission.  For    written permission, please contact <request_AT_jdom_DOT_org>. 4. Products derived from this software may not be called "JDOM", nor    may "JDOM" appear in their name, without prior written permission    from the JDOM Project Management <request_AT_jdom_DOT_org>. In addition, we request (but do not require) that you include in the end-user documentation provided with the redistribution and/or in the software itself an acknowledgement equivalent to the following:     "This product includes software developed by the      JDOM Project (http://www.jdom.org/)." Alternatively, the acknowledgment may be graphical using the logos available at http://www.jdom.org/images/logos. 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 THE JDOM AUTHORS OR THE PROJECT 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 the JDOM Project and was originally created by Jason Hunter <jhunter_AT_jdom_DOT_org> and Brett McLaughlin <brett_AT_jdom_DOT_org>.  For more information on the JDOM Project, please see <http://www.jdom.org/>. */package org.jdom.filter;import java.io.*;import org.jdom.*;/** * A Filter that only matches {@link org.jdom.Element} objects. * * @version $Revision: 1.20 $, $Date: 2007/11/10 05:29:00 $ * @author  Jools Enticknap * @author  Bradley S. Huffman */public class ElementFilter extends AbstractFilter {    private static final String CVS_ID =      "@(#) $RCSfile: ElementFilter.java,v $ $Revision: 1.20 $ $Date: 2007/11/10 05:29:00 $ $Name: jdom_1_1 $";    /** The element name */    private String name;    /** The element namespace */    private transient Namespace namespace;    /**     * Select only the Elements.     */    public ElementFilter() {}    /**     * Select only the Elements with the supplied name in any Namespace.     *     * @param name   The name of the Element.     */    public ElementFilter(String name) {        this.name   = name;    }    /**     * Select only the Elements with the supplied Namespace.     *     * @param namespace The namespace the Element lives in.     */    public ElementFilter(Namespace namespace) {        this.namespace = namespace;    }    /**     * Select only the Elements with the supplied name and Namespace.     *     * @param name   The name of the Element.     * @param namespace The namespace the Element lives in.     */    public ElementFilter(String name, Namespace namespace) {        this.name   = name;        this.namespace = namespace;    }    /**     * Check to see if the object matches a predefined set of rules.     *     * @param obj The object to verify.     * @return <code>true</code> if the objected matched a predfined     *           set of rules.     */    public boolean matches(Object obj) {        if (obj instanceof Element) {            Element el = (Element) obj;            return              (this.name == null || this.name.equals(el.getName())) &&              (this.namespace == null || this.namespace.equals(el.getNamespace()));        }        return false;    }    /**     * Returns whether the two filters are equivalent (i&#46;e&#46; the     * matching names and namespace are equivalent).     *     * @param  obj                   the object to compare against     * @return                     whether the two filters are equal     */    public boolean equals(Object obj) {        // Generated by IntelliJ        if (this == obj) return true;        if (!(obj instanceof ElementFilter)) return false;        final ElementFilter filter = (ElementFilter) obj;        if (name != null ? !name.equals(filter.name) : filter.name != null) return false;        if (namespace != null ? !namespace.equals(filter.namespace) : filter.namespace != null) return false;        return true;    }    public int hashCode() {        // Generated by IntelliJ        int result;        result = (name != null ? name.hashCode() : 0);        result = 29 * result + (namespace != null ? namespace.hashCode() : 0);        return result;    }    // Support a custom Namespace serialization so no two namespace    // object instances may exist for the same prefix/uri pair    private void writeObject(ObjectOutputStream out) throws IOException {        out.defaultWriteObject();        // We use writeObject() and not writeUTF() to minimize space        // This allows for writing pointers to already written strings        if (namespace != null) {            out.writeObject(namespace.getPrefix());            out.writeObject(namespace.getURI());        }        else {            out.writeObject(null);            out.writeObject(null);        }    }    private void readObject(ObjectInputStream in)            throws IOException, ClassNotFoundException {        in.defaultReadObject();        Object prefix = in.readObject();        Object uri = in.readObject();        if (prefix != null) {  // else leave namespace null here            namespace = Namespace.getNamespace((String) prefix, (String) uri);        }    }}