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1
2
3
4
5 package net.nutch.ontology;
6
7 import net.nutch.util.NutchConf;
8 import net.nutch.util.LogFormatter;
9
10 import com.hp.hpl.jena.ontology.Individual;
11 import com.hp.hpl.jena.ontology.OntClass;
12 import com.hp.hpl.jena.ontology.OntModel;
13 import com.hp.hpl.jena.ontology.OntModelSpec;
14 import com.hp.hpl.jena.ontology.OntResource;
15 import com.hp.hpl.jena.ontology.Restriction;
16 import com.hp.hpl.jena.rdf.model.Literal;
17 import com.hp.hpl.jena.rdf.model.Resource;
18 import com.hp.hpl.jena.rdf.model.ModelFactory;
19 import com.hp.hpl.jena.shared.PrefixMapping;
20
21 import java.util.Map  ;
22 import java.util.HashMap ;
23 import java.util.Hashtable ;
24 import java.util.Iterator ;
25 import java.util.List ;
26 import java.util.LinkedList ;
27
28 import java.util.logging.Logger ;
29
30 import java.io.PrintStream ;
31
32
39 public class OntologyImpl implements net.nutch.ontology.Ontology {
40 public static final Logger LOG =
41 LogFormatter.getLogger("net.nutch.ontology.Ontology");
42
43 public final static String DELIMITER_SEARCHTERM = " ";
44
45 private static Hashtable searchTerms = new Hashtable ();
46 private static Parser parser;
47
48 private static OntModel ontologyModel;
50
51 private static Ontology ontology = null;
52
53 private static Map m_anonIDs = new HashMap ();
54 private static int m_anonCount = 0;
55
56 public OntologyImpl() {
57 if (ontology == null) {
60 LOG.info( "creating new ontology");
61 parser = new OwlParser();
62 ontology = this;
63 }
64
65 if (ontologyModel == null)
66 ontologyModel =
67 ModelFactory.createOntologyModel(OntModelSpec.OWL_MEM, null);
68 }
70
71 public static Ontology getInstance () {
72 if (ontology == null) {
73 ontology = new net.nutch.ontology.OntologyImpl();
75 }
76 return ontology;
77 }
78
79 public void load (String [] urls) {
80 for (int i=0; i<urls.length; i++) {
81 String url = urls[i].trim();
82 if (!url.equals(""))
83 load(ontologyModel, url);
84 }
85 parser.parse(ontologyModel);
86 }
87
88 private void load (Object m, String url) {
89 try {
90 LOG.info( "reading "+url);
91 ((OntModel)m).read(url);
92 } catch (Exception e) {
93 LOG.severe("failed on attempting to read ontology "+url);
94 LOG.severe(e.getMessage());
95 StackTraceElement [] traces = e.getStackTrace();
96 for (int i=0; i<traces.length; i++) {
97 LOG.severe(traces[i].toString());
98 }
99 }
100 }
101
102 public static Parser getParser() {
103 if (parser == null) {
104 parser = new OwlParser();
105 }
106 return parser;
107 }
108
109 public static OntModel getModel() {
110 return (OntModel)ontologyModel;
111 }
112
113
117
120 public Iterator subclasses (String entitySearchTerm) {
121 Map classMap = retrieve(entitySearchTerm);
122 Map subclasses = new HashMap ();
123
124 Iterator iter = classMap.keySet().iterator();
125 while (iter.hasNext()) {
126 OntResource resource = (OntResource) iter.next();
128
129 if (resource instanceof OntClass) {
130 for (Iterator i=((OntClass)resource).listSubClasses(); i.hasNext();) {
132 OntResource subclass = (OntResource) i.next();
133 for (Iterator j=subclass.listLabels(null); j.hasNext();) {
134 Literal l = (Literal) j.next();
135 subclasses.put(l.toString(), "1");
136 }
137 }
138 for (Iterator i=((OntClass)resource).listInstances(); i.hasNext();) {
140 OntResource subclass = (OntResource) i.next();
141 for (Iterator j=subclass.listLabels(null); j.hasNext();) {
142 Literal l = (Literal) j.next();
143 subclasses.put(l.toString(), "1");
144 }
145 }
146 } else if (resource instanceof Individual) {
147 for (Iterator i=resource.listSameAs(); i.hasNext();) {
148 OntResource subclass = (OntResource) i.next();
149 for (Iterator j=subclass.listLabels(null); j.hasNext();) {
150 Literal l = (Literal) j.next();
151 subclasses.put(l.toString(), "1");
152 }
153 }
154 }
155 }
156
157 return subclasses.keySet().iterator();
158 }
159
160
163 public Iterator synonyms (String queryKeyPhrase) {
164 queryKeyPhrase = queryKeyPhrase.replaceAll("\\s+", "\\+");
166
167 Map classMap = retrieve(queryKeyPhrase);
168
169 Map synonyms = new HashMap ();
170
171 Iterator iter = classMap.keySet().iterator();
172 while (iter.hasNext()) {
173 OntResource resource = (OntResource) iter.next();
174
175 for (Iterator i=resource.listLabels(null); i.hasNext();) {
177 Literal l = (Literal) i.next();
178 synonyms.put(l.toString(), "1");
179 }
180
181 if (resource instanceof Individual) {
182 for (Iterator i=resource.listSameAs(); i.hasNext();) {
184 Individual individual = (Individual) i.next();
185 for (Iterator j =individual.listLabels(null); j.hasNext();) {
187 Literal l = (Literal) i.next();
188 synonyms.put(l.toString(), "1");
189 }
190 }
191 } else if (resource instanceof OntClass) {
192 for (Iterator i=((OntClass)resource).listEquivalentClasses();
194 i.hasNext();) {
195 OntClass equivClass = (OntClass) i.next();
196 for (Iterator j=equivClass.listLabels(null); j.hasNext();) {
198 Literal l = (Literal) j.next();
199 synonyms.put(l.toString(), "1");
200 }
201 }
202 }
203 }
204
205 return synonyms.keySet().iterator();
206 }
207
208 public static void addSearchTerm(String label, OntResource resource) {
209 Map m = retrieve(label);
210 if (m == null) {
211 m=new HashMap ();
212 }
213 m.put(resource, "1");
214 searchTerms.put(label.toLowerCase(), m);
215 }
216
217 public static Map retrieve(String label) {
218 Map m = (Map ) searchTerms.get(label.toLowerCase());
219 if (m==null) {
220 m = new HashMap ();
221 }
222 return m;
223 }
224
225 protected static void renderHierarchy( PrintStream out, OntClass cls,
226 List occurs, int depth ) {
227 renderClassDescription( out, cls, depth );
228 out.println();
229
230 if (cls.canAs( OntClass.class ) && !occurs.contains( cls )) {
232 for (Iterator i = cls.listSubClasses( true ); i.hasNext(); ) {
233 OntClass sub = (OntClass) i.next();
234
235 occurs.add( cls );
237 renderHierarchy( out, sub, occurs, depth + 1 );
238 occurs.remove( cls );
239 }
240 for (Iterator i=cls.listInstances(); i.hasNext(); ) {
241 Individual individual = (Individual) i.next();
242 renderURI(out, individual.getModel(), individual.getURI());
243 out.print(" [");
244 for (Iterator j=individual.listLabels(null); j.hasNext();) {
245 out.print(((Literal)j.next()).getString()+", ");
246 }
247 out.print("] ");
248 out.println();
249 }
250 }
251 }
252
253 public static void renderClassDescription( PrintStream out,
254 OntClass c, int depth ) {
255 indent( out, depth );
256
257 if (c.isRestriction()) {
258 renderRestriction( out, (Restriction) c.as( Restriction.class ) );
259 } else {
260 if (!c.isAnon()) {
261 out.print( "Class " );
262
264 out.print (c.getLocalName());
265
266 out.print( " [" );
267 for (Iterator i=c.listLabels(null); i.hasNext(); ) {
268 out.print(((Literal)i.next()).getString()+", ");
269 }
270 out.print( "] ");
271 } else {
272 renderAnonymous( out, c, "class" );
273 }
274 }
275 }
276
277 protected static void renderRestriction( PrintStream out, Restriction r ) {
278 if (!r.isAnon()) {
279 out.print( "Restriction " );
280 renderURI( out, r.getModel(), r.getURI() );
281 } else {
282 renderAnonymous( out, r, "restriction" );
283 }
284
285 out.print( " on property " );
286 renderURI( out, r.getModel(), r.getOnProperty().getURI() );
287 }
288
289 protected static void renderURI( PrintStream out,
290 PrefixMapping prefixes, String uri ) {
291 out.print( prefixes.usePrefix( uri ) );
292 }
293
294 protected static void renderAnonymous( PrintStream out,
295 Resource anon, String name ) {
296 String anonID = (String ) m_anonIDs.get( anon.getId() );
297 if (anonID == null) {
298 anonID = "a-" + m_anonCount++;
299 m_anonIDs.put( anon.getId(), anonID );
300 }
301
302 out.print( "Anonymous ");
303 out.print( name );
304 out.print( " with ID " );
305 out.print( anonID );
306 }
307
308 protected static void indent( PrintStream out, int depth ) {
309 for (int i = 0; i < depth; i++) {
310 out.print( " " );
311 }
312 }
313
314 public static void main( String [] args ) throws Exception {
315
316 Ontology ontology = OntologyFactory.getOntology();
317
318 String urls = NutchConf.get("extension.ontology.urls");
319 if (urls==null || urls.trim().equals("")) {
320 LOG.severe("No ontology url found.");
321 return;
322 }
323 ontology.load(urls.split("\\s+"));
324 LOG.info( "created new ontology");
325
326 for (Iterator i = getParser().rootClasses( getModel() );
327 i.hasNext(); ) {
328
329 OntClass c = (OntClass) i.next();
331
332 renderHierarchy(System.out, c, new LinkedList (), 0);
333 }
334
335 String [] terms =
336 new String [] { "Season" };
337
338 for (int i=0; i<terms.length; i++) {
339 Iterator iter = ontology.subclasses(terms[i]);
340 while (iter.hasNext()) {
341 System.out.println("subclass >> "+(String )iter.next());
342 }
343 }
344 }
345 }
346 |
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