001    /*
002     * SVGLoader.java
003     *
004     *
005     *  The Salamander Project - 2D and 3D graphics libraries in Java
006     *  Copyright (C) 2004 Mark McKay
007     *
008     *  This library is free software; you can redistribute it and/or
009     *  modify it under the terms of the GNU Lesser General Public
010     *  License as published by the Free Software Foundation; either
011     *  version 2.1 of the License, or (at your option) any later version.
012     *
013     *  This library is distributed in the hope that it will be useful,
014     *  but WITHOUT ANY WARRANTY; without even the implied warranty of
015     *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
016     *  Lesser General Public License for more details.
017     *
018     *  You should have received a copy of the GNU Lesser General Public
019     *  License along with this library; if not, write to the Free Software
020     *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
021     *
022     *  Mark McKay can be contacted at mark@kitfox.com.  Salamander and other
023     *  projects can be found at http://www.kitfox.com
024     *
025     * Created on February 18, 2004, 5:09 PM
026     */
027    
028    package com.kitfox.svg;
029    
030    
031    import java.util.*;
032    import java.net.*;
033    import org.xml.sax.*;
034    import org.xml.sax.helpers.DefaultHandler;
035    
036    import com.kitfox.svg.animation.*;
037    
038    /**
039     * @author Mark McKay
040     * @author <a href="mailto:mark@kitfox.com">Mark McKay</a>
041     */
042    public class SVGLoader extends DefaultHandler
043    {
044        final HashMap nodeClasses = new HashMap();
045        //final HashMap attribClasses = new HashMap();
046        final LinkedList buildStack = new LinkedList();
047    
048        final HashSet ignoreClasses = new HashSet();
049    
050        final SVGLoaderHelper helper;
051    
052        /**
053         * The diagram that represents the base of this SVG document we're loading.
054         * Will be augmented to include node indexing info and other useful stuff.
055         */
056        final SVGDiagram diagram;
057    
058    //    SVGElement loadRoot;
059    
060        //Used to keep track of document elements that are not part of the SVG namespace
061        int skipNonSVGTagDepth = 0;
062        int indent = 0;
063    
064        final boolean verbose;
065        
066        /** Creates a new instance of SVGLoader */
067        public SVGLoader(URI xmlBase, SVGUniverse universe)
068        {
069            this(xmlBase, universe, false);
070        }
071        
072        public SVGLoader(URI xmlBase, SVGUniverse universe, boolean verbose)
073        {
074            this.verbose = verbose;
075            
076            diagram = new SVGDiagram(xmlBase, universe);
077    
078            //Compile a list of important builder classes
079            nodeClasses.put("a", A.class);
080            nodeClasses.put("animate", Animate.class);
081            nodeClasses.put("animatecolor", AnimateColor.class);
082            nodeClasses.put("animatemotion", AnimateMotion.class);
083            nodeClasses.put("animatetransform", AnimateTransform.class);
084            nodeClasses.put("circle", Circle.class);
085            nodeClasses.put("clippath", ClipPath.class);
086            nodeClasses.put("defs", Defs.class);
087            nodeClasses.put("desc", Desc.class);
088            nodeClasses.put("ellipse", Ellipse.class);
089            nodeClasses.put("filter", Filter.class);
090            nodeClasses.put("font", Font.class);
091            nodeClasses.put("font-face", FontFace.class);
092            nodeClasses.put("g", Group.class);
093            nodeClasses.put("glyph", Glyph.class);
094            nodeClasses.put("hkern", Hkern.class);
095            nodeClasses.put("image", ImageSVG.class);
096            nodeClasses.put("line", Line.class);
097            nodeClasses.put("lineargradient", LinearGradient.class);
098            nodeClasses.put("marker", Marker.class);
099            nodeClasses.put("metadata", Metadata.class);
100            nodeClasses.put("missing-glyph", MissingGlyph.class);
101            nodeClasses.put("path", Path.class);
102            nodeClasses.put("pattern", PatternSVG.class);
103            nodeClasses.put("polygon", Polygon.class);
104            nodeClasses.put("polyline", Polyline.class);
105            nodeClasses.put("radialgradient", RadialGradient.class);
106            nodeClasses.put("rect", Rect.class);
107            nodeClasses.put("set", SetSmil.class);
108            nodeClasses.put("shape", ShapeElement.class);
109            nodeClasses.put("stop", Stop.class);
110            nodeClasses.put("style", Style.class);
111            nodeClasses.put("svg", SVGRoot.class);
112            nodeClasses.put("symbol", Symbol.class);
113            nodeClasses.put("text", Text.class);
114            nodeClasses.put("title", Title.class);
115            nodeClasses.put("tspan", Tspan.class);
116            nodeClasses.put("use", Use.class);
117    
118            ignoreClasses.add("midpointstop");
119    
120            //attribClasses.put("clip-path", StyleUrl.class);
121            //attribClasses.put("color", StyleColor.class);
122    
123            helper = new SVGLoaderHelper(xmlBase, universe, diagram);
124        }
125    
126        private String printIndent(int indent, String indentStrn)
127        {
128            StringBuffer sb = new StringBuffer();
129            for (int i = 0; i < indent; i++)
130            {
131                sb.append(indentStrn);
132            }
133            return sb.toString();
134        }
135        
136        public void startDocument() throws SAXException
137        {
138    //        System.err.println("Start doc");
139    
140    //        buildStack.clear();
141        }
142    
143        public void endDocument() throws SAXException
144        {
145    //        System.err.println("End doc");
146        }
147    
148        public void startElement(String namespaceURI, String sName, String qName, Attributes attrs) throws SAXException
149        {
150            if (verbose)
151            {
152                System.err.println(printIndent(indent, " ") + "Starting parse of tag " + sName+ ": " + namespaceURI);
153            }
154            indent++;
155            
156            if (skipNonSVGTagDepth != 0 || (!namespaceURI.equals("") && !namespaceURI.equals(SVGElement.SVG_NS)))
157            {
158                skipNonSVGTagDepth++;
159                return;
160            }
161            
162            sName = sName.toLowerCase();
163    
164    //javax.swing.JOptionPane.showMessageDialog(null, sName);
165    
166            Object obj = nodeClasses.get(sName);
167            if (obj == null)
168            {
169                if (!ignoreClasses.contains(sName))
170                {
171                    if (verbose)
172                    {
173                        System.err.println("SVGLoader: Could not identify tag '" + sName + "'");
174                    }
175                }
176                return;
177            }
178    
179    //Debug info tag depth
180    //for (int i = 0; i < buildStack.size(); i++) System.err.print(" ");
181    //System.err.println("+" + sName);
182    
183            try {
184                Class cls = (Class)obj;
185                SVGElement svgEle = (SVGElement)cls.newInstance();
186    
187                SVGElement parent = null;
188                if (buildStack.size() != 0) parent = (SVGElement)buildStack.getLast();
189                svgEle.loaderStartElement(helper, attrs, parent);
190    
191                buildStack.addLast(svgEle);
192            }
193            catch (Exception e)
194            {
195                e.printStackTrace();
196                throw new SAXException(e);
197            }
198    
199        }
200    
201        public void endElement(String namespaceURI, String sName, String qName)
202            throws SAXException
203        {
204            indent--;
205            if (verbose)
206            {
207                System.err.println(printIndent(indent, " ") + "Ending parse of tag " + sName+ ": " + namespaceURI);
208            }
209            
210            if (skipNonSVGTagDepth != 0)
211            {
212                skipNonSVGTagDepth--;
213                return;
214            }
215            
216            sName = sName.toLowerCase();
217    
218            Object obj = nodeClasses.get(sName);
219            if (obj == null) return;
220    
221    //Debug info tag depth
222    //for (int i = 0; i < buildStack.size(); i++) System.err.print(" ");
223    //System.err.println("-" + sName);
224    
225            try {
226                SVGElement svgEle = (SVGElement)buildStack.removeLast();
227    
228                svgEle.loaderEndElement(helper);
229    
230                SVGElement parent = null;
231                if (buildStack.size() != 0) parent = (SVGElement)buildStack.getLast();
232                //else loadRoot = (SVGElement)svgEle;
233    
234                if (parent != null) parent.loaderAddChild(helper, svgEle);
235                else diagram.setRoot((SVGRoot)svgEle);
236    
237            }
238            catch (Exception e)
239            {
240    e.printStackTrace();
241                throw new SAXException(e);
242            }
243        }
244    
245        public void characters(char buf[], int offset, int len)
246            throws SAXException
247        {
248            if (skipNonSVGTagDepth != 0)
249            {
250                return;
251            }
252    
253            if (buildStack.size() != 0)
254            {
255                SVGElement parent = (SVGElement)buildStack.getLast();
256                String s = new String(buf, offset, len);
257                parent.loaderAddText(helper, s);
258            }
259        }
260    
261        public void processingInstruction(String target, String data)
262            throws SAXException
263        {
264            //Check for external style sheet
265        }
266        
267    //    public SVGElement getLoadRoot() { return loadRoot; }
268        public SVGDiagram getLoadedDiagram() { return diagram; }
269    }