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16 package org.apache.cocoon.generation;
17
18 import java.io.IOException  ;
19 import java.util.HashMap ;
20 import java.util.Map ;
21
22 import org.apache.avalon.framework.logger.Logger;
23 import org.apache.avalon.framework.parameters.Parameters;
24 import org.apache.avalon.framework.service.ServiceException;
25 import org.apache.avalon.framework.service.ServiceManager;
26 import org.apache.cocoon.ProcessingException;
27 import org.apache.cocoon.components.source.SourceUtil;
28 import org.apache.cocoon.environment.Context;
29 import org.apache.cocoon.environment.ObjectModelHelper;
30 import org.apache.cocoon.environment.SourceResolver;
31 import org.apache.cocoon.xml.dom.DOMStreamer;
32 import org.apache.excalibur.source.TraversableSource;
33 import org.apache.excalibur.xml.xpath.PrefixResolver;
34 import org.apache.excalibur.xml.xpath.XPathProcessor;
35 import org.apache.regexp.RE;
36 import org.apache.regexp.RESyntaxException;
37 import org.w3c.dom.Document ;
38 import org.w3c.dom.NodeList ;
39 import org.xml.sax.SAXException ;
40 import org.xml.sax.helpers.AttributesImpl ;
41
42
98 public class XPathTraversableGenerator extends TraversableGenerator {
99
100
101 protected static final String XPATH_NODE_NAME = "xpath";
102
103 protected static final String QUERY_ATTR_NAME = "query";
104
105 protected static final String RESULT_DOCID_ATTR = "docid";
106
107
108 protected RE xmlRE;
109
110
111 protected Document doc;
112
113
114 protected String xpath;
115
116
117 protected XPathProcessor processor;
118
119
120 protected XPathPrefixResolver prefixResolver;
121
122
123 protected Context context;
124
125
126 public void setup(SourceResolver resolver, Map objectModel, String src, Parameters par)
127 throws ProcessingException, SAXException , IOException {
128 super.setup(resolver, objectModel, src, par);
129
130 int pointer;
132 if ((pointer = this.source.indexOf("#")) != -1) {
133 int endpointer = this.source.indexOf('?');
134 if (endpointer != -1) {
135 this.xpath = source.substring(pointer + 1, endpointer);
136 } else {
137 this.xpath = source.substring(pointer + 1);
138 }
139 this.source = src.substring(0, pointer);
140 if (endpointer != -1) {
141 this.source += src.substring(endpointer);
142 }
143 } else {
144 this.xpath = par.getParameter("xpath", null);
145 }
146 this.cacheKeyParList.add(this.xpath);
147 if (getLogger().isDebugEnabled()) {
148 getLogger().debug("Applying XPath: " + xpath + " to collection " + source);
149 }
150
151 String xmlFilesPattern = null;
152 try {
153 xmlFilesPattern = par.getParameter("xmlFiles", "\\.xml$");
154 this.cacheKeyParList.add(xmlFilesPattern);
155 this.xmlRE = new RE(xmlFilesPattern);
156 if (this.getLogger().isDebugEnabled()) {
157 this.getLogger().debug("pattern for XML files: " + xmlFilesPattern);
158 }
159 } catch (RESyntaxException rese) {
160 throw new ProcessingException("Syntax error in regexp pattern '"
161 + xmlFilesPattern + "'", rese);
162 }
163
164 String [] params = par.getNames();
165 this.prefixResolver = new XPathPrefixResolver(this.getLogger());
166 for (int i = 0; i < params.length; i++) {
167 if (params[i].startsWith("xmlns:")) {
168 String paramValue = par.getParameter(params[i], "");
169 String paramName = params[i].substring(6);
170 if (getLogger().isDebugEnabled()) {
171 getLogger().debug("add param to prefixResolver: " + paramName);
172 }
173 this.prefixResolver.addPrefix(paramName, paramValue);
174 }
175 }
176
177 this.context = ObjectModelHelper.getContext(objectModel);
178 }
179
180 public void service(ServiceManager manager) throws ServiceException {
181 super.service(manager);
182 processor = (XPathProcessor)manager.lookup(XPathProcessor.ROLE);
183 }
184
185 public void dispose() {
186 if ( this.manager != null ) {
187 this.manager.release( processor );
188 this.processor = null;
189 }
190 super.dispose();
191 }
192
193 protected void addContent(TraversableSource source)
194 throws SAXException , ProcessingException {
195 super.addContent(source);
196 if (!source.isCollection() && isXML(source) && xpath != null) {
197 performXPathQuery(source);
198 }
199 }
200
201
208 protected boolean isXML(TraversableSource path) {
209 String mimeType = this.context.getMimeType(path.getName());
210 return this.xmlRE.match(path.getName()) || "text/xml".equalsIgnoreCase(mimeType);
211 }
212
213
218 protected void performXPathQuery(TraversableSource in) throws SAXException {
219 doc = null;
220 try {
221 doc = SourceUtil.toDOM(this.manager, "text/xml", in);
222 } catch (SAXException se) {
223 getLogger().error("Warning:" + in.getName() + " is not a valid XML document. Ignoring");
224 } catch (Exception e) {
225 this.getLogger().error("Unable to resolve and parse document" + e);
226 }
227 if (doc != null) {
228 NodeList nl = processor.selectNodeList(doc.getDocumentElement(), xpath, this.prefixResolver);
229 final String id = in.getName();
230 AttributesImpl attributes = new AttributesImpl ();
231 attributes.addAttribute("", RESULT_DOCID_ATTR, RESULT_DOCID_ATTR," CDATA", id);
232 attributes.addAttribute("", QUERY_ATTR_NAME, QUERY_ATTR_NAME, "CDATA",xpath);
233 super.contentHandler.startElement(URI, XPATH_NODE_NAME, PREFIX + ":" + XPATH_NODE_NAME, attributes);
234 DOMStreamer ds = new DOMStreamer(super.xmlConsumer);
235 for (int i = 0; i < nl.getLength(); i++) {
236 ds.stream(nl.item(i));
237 }
238 super.contentHandler.endElement(URI, XPATH_NODE_NAME, PREFIX + ":" + XPATH_NODE_NAME);
239 }
240 }
241
242
246 public void recycle() {
247 this.xpath = null;
248 this.doc = null;
249 this.xmlRE = null;
250 this.prefixResolver = null;
251 this.context = null;
252 super.recycle();
253 }
254
255
258 static class XPathPrefixResolver implements PrefixResolver {
259
260 private Map params;
261
262 private Logger logger;
263
264 public XPathPrefixResolver(Logger logger) {
265 this.params = new HashMap ();
266 this.logger = logger;
267 }
268
269
274 public String prefixToNamespace(String prefix) {
275 if (this.logger.isDebugEnabled()) {
276 this.logger.debug("prefix: " + prefix);
277 }
278 if (this.params.containsKey(prefix)) {
279 if(this.logger.isDebugEnabled()) {
280 this.logger.debug("prefix; " + prefix + " - namespace: " + this.params.get(prefix));
281 }
282 return (String ) this.params.get(prefix);
283 }
284 return null;
285 }
286
287 public void addPrefix(String prefix, String uri) {
288 this.params.put(prefix, uri);
289 }
290 }
291 }
292 |
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