    001    /* ========================================================================
    002     * JCommon : a free general purpose class library for the Java(tm) platform
    003     * ========================================================================
    004     *
    005     * (C) Copyright 2000-2005, by Object Refinery Limited and Contributors.
    006     *
    007     * Project Info:  http://www.jfree.org/jcommon/index.html
    008     *
    009     * This library is free software; you can redistribute it and/or modify it
    010     * under the terms of the GNU Lesser General Public License as published by
    011     * the Free Software Foundation; either version 2.1 of the License, or
    012     * (at your option) any later version.
    013     *
    014     * This library is distributed in the hope that it will be useful, but
    015     * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
    016     * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
    017     * License for more details.
    018     *
    019     * You should have received a copy of the GNU Lesser General Public
    020     * License along with this library; if not, write to the Free Software
    021     * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
    022     * USA.
    023     *
    024     * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
    025     * in the United States and other countries.]
    026     *
    027     * --------------------
    028     * ListReadHandler.java
    029     * --------------------
    030     * (C)opyright 2003, 2004, by Thomas Morgner and Contributors.
    031     *
    032     * Original Author:  Thomas Morgner;
    033     * Contributor(s):   David Gilbert (for Object Refinery Limited);
    034     *
    035     * $Id: ListReadHandler.java,v 1.3 2005/10/18 13:33:32 mungady Exp $
    036     *
    037     * Changes
    038     * -------
    039     * 12-Nov-2003 : Initial version (TM);
    040     *
    041     */
    042
    043    package org.jfree.xml.parser.coretypes;
    044
    045    import java.util.ArrayList;
    046    import java.util.LinkedList;
    047    import java.util.List;
    048    import java.util.Stack;
    049    import java.util.Vector;
    050
    051    import org.jfree.xml.parser.AbstractXmlReadHandler;
    052    import org.jfree.xml.parser.XmlReadHandler;
    053    import org.jfree.xml.parser.XmlReaderException;
    054    import org.xml.sax.Attributes;
    055    import org.xml.sax.SAXException;
    056
    057    /**
    058     * A SAX handler for reading a list from an XML element.
    059     */
    060    public class ListReadHandler extends AbstractXmlReadHandler {
    061
    062        /** The list under construction. */
    063        private List retval;
    064
    065        /** The handlers. */
    066        private ArrayList handlers;
    067
    068        /** The type of list ('array-list', 'linked-list', 'stack', 'vector'). */
    069        private String listType;
    070
    071        /**
    072         * Default constructor.
    073         */
    074        public ListReadHandler() {
    075            super();
    076        }
    077
    078        /**
    079         * Start parsing.
    080         *
    081         * @param attrs  the attributes.
    082         *
    083         * @throws SAXException if there is a parsing error.
    084         */
    085        protected void startParsing(final Attributes attrs) throws SAXException {
    086            this.listType = attrs.getValue("type");
    087            if (this.listType == null) {
    088                this.listType = "array-list";
    089            }
    090            this.handlers = new ArrayList();
    091        }
    092
    093        /**
    094         * Gets a handler for a child.
    095         *
    096         * @param tagName  the tag name.
    097         * @param atts  the attributes.
    098         *
    099         * @return A handler.
    100         *
    101         * @throws XmlReaderException if there is a problem with the reader.
    102         * @throws SAXException if there is a parsing error.
    103         */
    104        protected XmlReadHandler getHandlerForChild(final String tagName, final Attributes atts)
    105            throws XmlReaderException, SAXException {
    106            final XmlReadHandler handler = getRootHandler().createHandler(Object.class, tagName, atts);
    107            this.handlers.add(handler);
    108            return handler;
    109        }
    110
    111        /**
    112         * Parsing is finished.
    113         *
    114         * @throws SAXException if there is a parsing error.
    115         * @throws XmlReaderException if there is a problem with the reader.
    116         *
    117         */
    118        protected void doneParsing() throws SAXException, XmlReaderException {
    119            final XmlReadHandler[] handler = (XmlReadHandler[])
    120            this.handlers.toArray(new XmlReadHandler[this.handlers.size()]);
    121            this.retval = createList(handler.length);
    122            for (int i = 0; i < handler.length; i++) {
    123                this.retval.add(handler[i].getObject());
    124            }
    125            this.handlers.clear();
    126        }
    127
    128        /**
    129         * Creates a list.
    130         *
    131         * @param initialSize  the initial size.
    132         *
    133         * @return A new list.
    134         */
    135        private List createList(final int initialSize) {
    136            if (this.listType.equals("stack")) {
    137                return new Stack();
    138            }
    139            if (this.listType.equals("linked-list")) {
    140                return new LinkedList();
    141            }
    142            if (this.listType.equals("vector")) {
    143                return new Vector(initialSize);
    144            }
    145            return new ArrayList(initialSize);
    146        }
    147
    148        /**
    149         * Returns the object under construction.
    150         *
    151         * @return The list.
    152         */
    153        public Object getObject() {
    154            return this.retval;
    155        }
    156
    157    }