001/*
002 * Copyright 2006 - 2013
003 *      Stefan Balev    <stefan.balev@graphstream-project.org>
004 *      Julien Baudry   <julien.baudry@graphstream-project.org>
005 *      Antoine Dutot   <antoine.dutot@graphstream-project.org>
006 *      Yoann Pigné         <yoann.pigne@graphstream-project.org>
007 *      Guilhelm Savin  <guilhelm.savin@graphstream-project.org>
008 *  
009 * GraphStream is a library whose purpose is to handle static or dynamic
010 * graph, create them from scratch, file or any source and display them.
011 * 
012 * This program is free software distributed under the terms of two licenses, the
013 * CeCILL-C license that fits European law, and the GNU Lesser General Public
014 * License. You can  use, modify and/ or redistribute the software under the terms
015 * of the CeCILL-C license as circulated by CEA, CNRS and INRIA at the following
016 * URL <http://www.cecill.info> or under the terms of the GNU LGPL as published by
017 * the Free Software Foundation, either version 3 of the License, or (at your
018 * option) any later version.
019 * 
020 * This program is distributed in the hope that it will be useful, but WITHOUT ANY
021 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
022 * PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more details.
023 * 
024 * You should have received a copy of the GNU Lesser General Public License
025 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
026 * 
027 * The fact that you are presently reading this means that you have had
028 * knowledge of the CeCILL-C and LGPL licenses and that you accept their terms.
029 */
030package org.graphstream.stream.file.gexf;
031
032import java.io.Writer;
033import java.util.LinkedList;
034
035import javax.xml.stream.FactoryConfigurationError;
036import javax.xml.stream.XMLOutputFactory;
037import javax.xml.stream.XMLStreamException;
038import javax.xml.stream.XMLStreamWriter;
039
040public class SmartXMLWriter {
041        public final XMLStreamWriter stream;
042
043        boolean smart;
044        int depth;
045        LinkedList<Integer> childrenCount;
046
047        public SmartXMLWriter(Writer output, boolean smart)
048                        throws XMLStreamException, FactoryConfigurationError {
049                stream = XMLOutputFactory.newFactory().createXMLStreamWriter(output);
050                stream.writeStartDocument("UTF-8", "1.0");
051
052                this.smart = smart;
053                this.depth = 0;
054                this.childrenCount = new LinkedList<Integer>();
055                this.childrenCount.add(0);
056        }
057
058        public void startElement(String name) throws XMLStreamException {
059                if (smart) {
060                        stream.writeCharacters("\n");
061
062                        for (int i = 0; i < depth; i++)
063                                stream.writeCharacters(" ");
064                }
065
066                childrenCount.set(0, childrenCount.get(0) + 1);
067                childrenCount.addFirst(0);
068
069                stream.writeStartElement(name);
070                depth++;
071        }
072
073        public void endElement() throws XMLStreamException {
074                depth--;
075
076                boolean leaf = (childrenCount.pop() == 0);
077
078                if (smart && !leaf) {
079                        stream.writeCharacters("\n");
080
081                        for (int i = 0; i < depth; i++)
082                                stream.writeCharacters(" ");
083                }
084
085                stream.writeEndElement();
086        }
087
088        public void leafWithText(String name, String content)
089                        throws XMLStreamException {
090                startElement(name);
091                stream.writeCharacters(content);
092                endElement();
093        }
094
095        public void flush() {
096                try {
097                        stream.flush();
098                } catch (XMLStreamException e) {
099                        // Ignored
100                }
101        }
102
103        public void close() throws XMLStreamException {
104                stream.writeEndDocument();
105                stream.flush();
106
107                stream.close();
108        }
109}