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1
16 package org.apache.cocoon.generation;
17
18 import org.apache.avalon.framework.activity.Initializable;
19 import org.apache.avalon.framework.configuration.Configurable;
20 import org.apache.avalon.framework.configuration.Configuration;
21 import org.apache.avalon.framework.configuration.ConfigurationException;
22 import org.apache.avalon.framework.parameters.Parameters;
23
24 import org.apache.cocoon.ProcessingException;
25 import org.apache.cocoon.ResourceNotFoundException;
26 import org.apache.cocoon.caching.CacheableProcessingComponent;
27 import org.apache.cocoon.environment.SourceResolver;
28 import org.apache.cocoon.util.Deprecation;
29
30 import org.apache.excalibur.source.SourceValidity;
31 import org.xml.sax.SAXException  ;
32 import org.xml.sax.helpers.AttributesImpl ;
33 import org.xmldb.api.DatabaseManager;
34 import org.xmldb.api.base.Collection;
35 import org.xmldb.api.base.Database;
36 import org.xmldb.api.base.XMLDBException;
37
38 import java.io.IOException ;
39 import java.util.Map ;
40
41
63 public class XMLDBCollectionGenerator extends ServiceableGenerator
64 implements CacheableProcessingComponent, Configurable, Initializable {
65
66 protected static final String URI =
67 "http://apache.org/cocoon/xmldb/1.0";
68 protected static final String PREFIX = "collection";
69 protected static final String RESOURCE_COUNT_ATTR = "resources";
70 protected static final String COLLECTION_COUNT_ATTR = "collections";
71 protected static final String COLLECTION = "collection";
72 protected static final String QCOLLECTION = PREFIX + ":collection";
73 protected static final String RESOURCE = "resource";
74 protected static final String QRESOURCE = PREFIX + ":resource";
75
76 protected String driver;
77 protected String base;
78 protected String col;
79 protected Database database;
80 protected Collection collection;
81 protected final AttributesImpl attributes = new AttributesImpl ();
82
83
87 public void recycle() {
88 super.recycle();
89 this.col = null;
90 this.collection = null;
91 }
92
93
107 public void configure(Configuration conf) throws ConfigurationException {
108 this.driver = conf.getChild("driver").getValue();
109 this.base = conf.getChild("base").getValue();
110 }
111
112
117 public void initialize() throws Exception {
118 try {
119 Class c = Class.forName(driver);
120 database = (Database)c.newInstance();
121 DatabaseManager.registerDatabase(database);
122 } catch (XMLDBException xde) {
123 getLogger().error("Unable to connect to the XML:DB database");
124 throw new ProcessingException("Unable to connect to the XML DB"
125 + xde.getMessage());
126 } catch (Exception e) {
127 getLogger().error("There was a problem setting up the connection");
128 getLogger().error("Make sure that your driver is available");
129 throw new ProcessingException("Problem setting up the connection: "
130 + e.getMessage());
131 }
132 }
133
134 public void setup(SourceResolver resolver,
135 Map objectModel,
136 String src,
137 Parameters par)
138 throws ProcessingException, SAXException ,IOException {
139 Deprecation.logger.warn("The XMLDBCollectionGenerator is deprecated. Use the XML:DB pseudo protocol instead");
140 super.setup(resolver, objectModel, src, par);
141 }
142
143
146 public SourceValidity getValidity() {
147 return null;
148 }
149
150
153 public java.io.Serializable getKey() {
154 return null;
155 }
156
157
163 public void generate()
164 throws IOException , SAXException , ProcessingException {
165
167 col = source;
169
170 try {
171 collection = DatabaseManager.getCollection(base + col);
172 if (collection == null) {
173 throw new ResourceNotFoundException("Collection " + col +
174 " not found");
175 }
176
177 collectionToSAX(collection);
178 collection.close();
179 } catch (XMLDBException xde) {
180 throw new ProcessingException("Unable to fetch content '"
181 + source + "':" + xde.getMessage());
182 } catch (NullPointerException npe) {
183 getLogger().error("The XML:DB driver raised an exception");
184 getLogger().error("probably the document was not found");
185 throw new ProcessingException("Null pointer exception while " +
186 "retrieving document : " + npe.getMessage());
187 }
188 }
189
190
195 public void collectionToSAX(Collection collection)
196 throws SAXException {
197
198 String ncollections;
199 String nresources;
200 String [] resources;
201 String [] collections;
202
203 try {
204 ncollections = Integer.toString(collection.getChildCollectionCount());
205 nresources = Integer.toString(collection.getResourceCount());
206
207 attributes.clear();
208 attributes.addAttribute("", RESOURCE_COUNT_ATTR,
209 RESOURCE_COUNT_ATTR, "CDATA", nresources);
210 attributes.addAttribute("", COLLECTION_COUNT_ATTR,
211 COLLECTION_COUNT_ATTR, "CDATA", ncollections);
212
213 collections = collection.listChildCollections();
214 resources = collection.listResources();
215
216 this.xmlConsumer.startDocument();
217 this.xmlConsumer.startPrefixMapping(PREFIX, URI);
218
219 this.xmlConsumer.startElement(URI, "collections",
220 "collection:collections", attributes);
221
222
224 for (int i = 0; i < collections.length; i++) {
225 attributes.clear();
226 attributes.addAttribute("", "name", "name", "CDATA", collections[i]);
227 this.xmlConsumer.startElement(URI, COLLECTION,
228 QCOLLECTION, attributes);
229 this.xmlConsumer.endElement(URI, COLLECTION, COLLECTION);
230 }
231
232
234 for (int i = 0; i < resources.length; i++) {
235 attributes.clear();
236 attributes.addAttribute("", "name", "name", "CDATA", resources[i]);
237 this.xmlConsumer.startElement(URI, RESOURCE,
238 QRESOURCE, attributes);
239 this.xmlConsumer.endElement(URI, RESOURCE, RESOURCE);
240 }
241
242 this.xmlConsumer.endElement(URI, "collections",
243 "collection:collections");
244
245 this.xmlConsumer.endPrefixMapping(PREFIX);
246 this.xmlConsumer.endDocument();
247 } catch (XMLDBException xde) {
248 getLogger().warn("Collection listing failed: " + xde.getMessage());
249 throw new SAXException ("Collection listing failed: " + xde.getMessage());
250 }
251 }
252 }
253 |
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