|
1 package prefuse.data.io;
2
3 import java.io.InputStream  ;
4 import java.util.Date ;
5 import java.util.HashMap ;
6
7 import javax.xml.parsers.SAXParser ;
8 import javax.xml.parsers.SAXParserFactory ;
9
10 import org.xml.sax.Attributes ;
11 import org.xml.sax.SAXException ;
12 import org.xml.sax.helpers.DefaultHandler ;
13
14 import prefuse.data.Graph;
15 import prefuse.data.Schema;
16 import prefuse.data.Table;
17 import prefuse.data.parser.DataParseException;
18 import prefuse.data.parser.DataParser;
19 import prefuse.data.parser.ParserFactory;
20 import prefuse.util.collections.IntIterator;
21
22
23
32 public class GraphMLReader extends AbstractGraphReader implements GraphReader {
33
34
37 public Graph readGraph(InputStream is) throws DataIOException {
38 try {
39 SAXParserFactory factory = SAXParserFactory.newInstance();
40 SAXParser saxParser = factory.newSAXParser();
41
42 GraphMLHandler handler = new GraphMLHandler();
43 saxParser.parse(is, handler);
44 return handler.getGraph();
45 } catch ( Exception e ) {
46 if ( e instanceof DataIOException ) {
47 throw (DataIOException)e;
48 } else {
49 throw new DataIOException(e);
50 }
51 }
52 }
53
54
57 public interface Tokens {
58 public static final String ID = "id";
59 public static final String GRAPH = "graph";
60 public static final String EDGEDEF = "edgedefault";
61 public static final String DIRECTED = "directed";
62 public static final String UNDIRECTED = "undirected";
63
64 public static final String KEY = "key";
65 public static final String FOR = "for";
66 public static final String ALL = "all";
67 public static final String ATTRNAME = "attr.name";
68 public static final String ATTRTYPE = "attr.type";
69 public static final String DEFAULT = "default";
70
71 public static final String NODE = "node";
72 public static final String EDGE = "edge";
73 public static final String SOURCE = "source";
74 public static final String TARGET = "target";
75 public static final String DATA = "data";
76 public static final String TYPE = "type";
77
78 public static final String INT = "int";
79 public static final String INTEGER = "integer";
80 public static final String LONG = "long";
81 public static final String FLOAT = "float";
82 public static final String DOUBLE = "double";
83 public static final String REAL = "real";
84 public static final String BOOLEAN = "boolean";
85 public static final String STRING = "string";
86 public static final String DATE = "date";
87 }
88
89
92 public static class GraphMLHandler extends DefaultHandler implements Tokens
93 {
94 protected ParserFactory m_pf = ParserFactory.getDefaultFactory();
95
96 protected static final String SRC = Graph.DEFAULT_SOURCE_KEY;
97 protected static final String TRG = Graph.DEFAULT_TARGET_KEY;
98 protected static final String SRCID = SRC+'_'+ID;
99 protected static final String TRGID = TRG+'_'+ID;
100
101 protected Schema m_nsch = new Schema();
102 protected Schema m_esch = new Schema();
103
104 protected String m_graphid;
105 protected Graph m_graph = null;
106 protected Table m_nodes;
107 protected Table m_edges;
108
109 protected String m_id;
111 protected String m_for;
112 protected String m_name;
113 protected String m_type;
114 protected String m_dflt;
115
116 protected StringBuffer m_sbuf = new StringBuffer ();
117
118 private String m_key;
120 private int m_row = -1;
121 private Table m_table = null;
122 protected HashMap m_nodeMap = new HashMap ();
123 protected HashMap m_idMap = new HashMap ();
124
125 private boolean m_directed = false;
126 private boolean inSchema;
127
128 public void startDocument() {
129 m_nodeMap.clear();
130 inSchema = true;
131
132 m_esch.addColumn(SRC, int.class);
133 m_esch.addColumn(TRG, int.class);
134 m_esch.addColumn(SRCID, String .class);
135 m_esch.addColumn(TRGID, String .class);
136 }
137
138 public void endDocument() throws SAXException {
139 IntIterator rows = m_edges.rows();
141 while (rows.hasNext()) {
142 int r = rows.nextInt();
143
144 String src = m_edges.getString(r, SRCID);
145 if (!m_nodeMap.containsKey(src)) {
146 throw new SAXException (
147 "Tried to create edge with source node id=" + src
148 + " which does not exist.");
149 }
150 int s = ((Integer ) m_nodeMap.get(src)).intValue();
151 m_edges.setInt(r, SRC, s);
152
153 String trg = m_edges.getString(r, TRGID);
154 if (!m_nodeMap.containsKey(trg)) {
155 throw new SAXException (
156 "Tried to create edge with target node id=" + trg
157 + " which does not exist.");
158 }
159 int t = ((Integer ) m_nodeMap.get(trg)).intValue();
160 m_edges.setInt(r, TRG, t);
161 }
162 m_edges.removeColumn(SRCID);
163 m_edges.removeColumn(TRGID);
164
165 m_graph = new Graph(m_nodes, m_edges, m_directed);
167 if (m_graphid != null)
168 m_graph.putClientProperty(ID, m_graphid);
169 }
170
171 public void startElement(String namespaceURI, String localName,
172 String qName, Attributes atts)
173 {
174 m_sbuf.delete(0, m_sbuf.length());
176
177 if ( qName.equals(GRAPH) )
178 {
179 String edef = atts.getValue(EDGEDEF);
181 m_directed = DIRECTED.equalsIgnoreCase(edef);
182 m_graphid = atts.getValue(ID);
183 }
184 else if ( qName.equals(KEY) )
185 {
186 if ( !inSchema ) {
187 error("\""+KEY+"\" elements can not"
188 + " occur after the first node or edge declaration.");
189 }
190 m_for = atts.getValue(FOR);
191 m_id = atts.getValue(ID);
192 m_name = atts.getValue(ATTRNAME);
193 m_type = atts.getValue(ATTRTYPE);
194 }
195 else if ( qName.equals(NODE) )
196 {
197 schemaCheck();
198
199 m_row = m_nodes.addRow();
200
201 String id = atts.getValue(ID);
202 m_nodeMap.put(id, new Integer (m_row));
203 m_table = m_nodes;
204 }
205 else if ( qName.equals(EDGE) )
206 {
207 schemaCheck();
208
209 m_row = m_edges.addRow();
210
211 m_edges.setString(m_row, SRCID, atts.getValue(SRC));
219 m_edges.setString(m_row, TRGID, atts.getValue(TRG));
220
221 m_table = m_edges;
230 }
231 else if ( qName.equals(DATA) )
232 {
233 m_key = atts.getValue(KEY);
234 }
235 }
236
237 public void endElement(String namespaceURI,
238 String localName, String qName)
239 {
240 if ( qName.equals(DEFAULT) ) {
241 m_dflt = m_sbuf.toString();
243 }
244 else if ( qName.equals(KEY) ) {
245 addToSchema();
247 }
248 else if ( qName.equals(DATA) ) {
249 String value = m_sbuf.toString();
251 String name = (String )m_idMap.get(m_key);
252 Class type = m_table.getColumnType(name);
253 try {
254 Object val = parse(value, type);
255 m_table.set(m_row, name, val);
256 } catch ( DataParseException dpe ) {
257 error(dpe);
258 }
259 }
260 else if ( qName.equals(NODE) || qName.equals(EDGE) ) {
261 m_row = -1;
262 m_table = null;
263 }
264 }
265
266 public void characters(char[] ch, int start, int length) throws SAXException {
267 m_sbuf.append(ch, start, length);
268 }
269
270
272 protected void schemaCheck() {
273 if ( inSchema ) {
274 m_nsch.lockSchema();
275 m_esch.lockSchema();
276 m_nodes = m_nsch.instantiate();
277 m_edges = m_esch.instantiate();
278 inSchema = false;
279 }
280 }
281
282 protected void addToSchema() {
283 if ( m_name == null || m_name.length() == 0 )
284 error("Empty "+KEY+" name.");
285 if ( m_type == null || m_type.length() == 0 )
286 error("Empty "+KEY+" type.");
287
288 try {
289 Class type = parseType(m_type);
290 Object dflt = m_dflt==null ? null : parse(m_dflt, type);
291
292 if ( m_for == null || m_for.equals(ALL) ) {
293 m_nsch.addColumn(m_name, type, dflt);
294 m_esch.addColumn(m_name, type, dflt);
295 } else if ( m_for.equals(NODE) ) {
296 m_nsch.addColumn(m_name, type, dflt);
297 } else if ( m_for.equals(EDGE) ) {
298 m_esch.addColumn(m_name, type, dflt);
299 } else {
300 error("Unrecognized \""+FOR+"\" value: "+ m_for);
301 }
302 m_idMap.put(m_id, m_name);
303
304 m_dflt = null;
305 } catch ( DataParseException dpe ) {
306 error(dpe);
307 }
308 }
309
310 protected Class parseType(String type) {
311 type = type.toLowerCase();
312 if ( type.equals(INT) || type.equals(INTEGER) ) {
313 return int.class;
314 } else if ( type.equals(LONG) ) {
315 return long.class;
316 } else if ( type.equals(FLOAT) ) {
317 return float.class;
318 } else if ( type.equals(DOUBLE) || type.equals(REAL)) {
319 return double.class;
320 } else if ( type.equals(BOOLEAN) ) {
321 return boolean.class;
322 } else if ( type.equals(STRING) ) {
323 return String .class;
324 } else if ( type.equals(DATE) ) {
325 return Date .class;
326 } else {
327 error("Unrecognized data type: "+type);
328 return null;
329 }
330 }
331
332 protected Object parse(String s, Class type)
333 throws DataParseException
334 {
335 DataParser dp = m_pf.getParser(type);
336 return dp.parse(s);
337 }
338
339 public Graph getGraph() {
340 return m_graph;
341 }
342
343 protected void error(String s) {
344 throw new RuntimeException (s);
345 }
346
347 protected void error(Exception e) {
348 throw new RuntimeException (e);
349 }
350
351 }
353 } |
Popular Tags |
Java API By Example, From Geeks To Geeks.