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1
16 package org.apache.cocoon.components.source.impl;
17
18
19 import java.io.InputStream  ;
20 import java.io.IOException ;
21 import java.io.OutputStream ;
22 import java.io.ByteArrayOutputStream ;
23 import java.io.ByteArrayInputStream ;
24 import java.net.MalformedURLException ;
25 import java.util.Map ;
26
27 import org.apache.avalon.framework.configuration.ConfigurationException;
28 import org.apache.avalon.framework.logger.Logger;
29 import org.apache.avalon.framework.service.ServiceException;
30 import org.apache.avalon.framework.service.ServiceManager;
31 import org.apache.avalon.framework.service.ServiceSelector;
32
33 import org.apache.excalibur.source.ModifiableSource;
34 import org.apache.excalibur.source.SourceException;
35 import org.apache.excalibur.source.impl.AbstractSource;
36 import org.apache.excalibur.xml.sax.SAXParser;
37 import org.apache.excalibur.xml.sax.XMLizable;
38
39 import org.apache.cocoon.components.modules.input.InputModule;
40 import org.apache.cocoon.components.modules.output.OutputModule;
41 import org.apache.cocoon.serialization.XMLSerializer;
42 import org.apache.cocoon.util.jxpath.DOMFactory;
43 import org.apache.cocoon.xml.dom.DOMBuilder;
44 import org.apache.cocoon.xml.dom.DOMStreamer;
45
46 import org.apache.commons.jxpath.JXPathContext;
47
48 import org.w3c.dom.Document ;
49 import org.w3c.dom.Node ;
50
51 import org.xml.sax.ContentHandler ;
52 import org.xml.sax.InputSource ;
53 import org.xml.sax.SAXException ;
54
55
72
73 public class XModuleSource
74 extends AbstractSource
75 implements ModifiableSource, XMLizable, DOMBuilder.Listener {
76
77 private final static String SCHEME = "xmodule";
78 private String attributeType;
79 private String attributeName;
80 private String xPath;
81 private ServiceManager manager;
82 private Map objectModel;
83 private Logger logger;
84
85
89 public XModuleSource( Map objectModel, String uri,
90 ServiceManager manager, Logger logger )
91 throws MalformedURLException {
92
93 this.objectModel = objectModel;
94 this.manager = manager;
95 this.logger = logger;
96
97 setSystemId( uri );
98
99 int start = 0;
101 int end = uri.indexOf( ':' );
102 if ( end == -1 )
103 throw new MalformedURLException ("Malformed uri for xmodule source (cannot find scheme) : " + uri);
104
105 String scheme = uri.substring( start, end );
106 if ( !SCHEME.equals( scheme ) )
107 throw new MalformedURLException ("Malformed uri for a xmodule source : " + uri);
108
109 setScheme( scheme );
110
111 start = end + 1;
113 end = uri.indexOf( ':', start );
114 if ( end == -1 ) {
115 throw new MalformedURLException ("Malformed uri for xmodule source (cannot find attribute type) : " + uri);
116 }
117 this.attributeType = uri.substring( start, end );
118
119 start = end + 1;
121 end = uri.indexOf( '#', start );
122
123 if ( end == -1 )
124 end = uri.length();
125
126 if ( end == start )
127 throw new MalformedURLException ("Malformed uri for xmodule source (cannot find attribute name) : " + uri);
128
129 this.attributeName = uri.substring( start, end );
130
131 start = end + 1;
133 this.xPath = start < uri.length() ? uri.substring( start ) : "";
134 }
135
136
140
141 public void toSAX(ContentHandler handler)
142 throws SAXException {
143
144 Object obj = getInputAttribute( this.attributeType, this.attributeName );
145 if ( obj == null )
146 throw new SAXException ( " The attribute: " + this.attributeName +
147 " is empty" );
148
149 if ( !(this.xPath.length() == 0 || this.xPath.equals( "/" )) ) {
150 JXPathContext context = JXPathContext.newContext( obj );
151
152 obj = context.getPointer( this.xPath ).getNode();
153
154 if ( obj == null )
155 throw new SAXException ( "the xpath: " + this.xPath +
156 " applied on the attribute: " +
157 this.attributeName +
158 " returns null");
159 }
160
161 if ( obj instanceof Document ) {
162 DOMStreamer domStreamer = new DOMStreamer( handler );
163 domStreamer.stream( (Document )obj );
164 } else if ( obj instanceof Node ) {
165 DOMStreamer domStreamer = new DOMStreamer( handler );
166 handler.startDocument();
167 domStreamer.stream( (Node )obj );
168 handler.endDocument();
169 } else if ( obj instanceof XMLizable ) {
170 ((XMLizable)obj).toSAX( handler );
171 } else {
172 throw new SAXException ( "The object type: " + obj.getClass() +
173 " could not be serialized to XML: " + obj );
174 }
175 }
176
177
182 public InputStream getInputStream() throws IOException , SourceException {
184 if ( this.logger.isDebugEnabled() ) {
185 this.logger.debug( "Getting InputStream for " + getURI() );
186 }
187
188
190 XMLSerializer serializer = new XMLSerializer();
191 ByteArrayInputStream inputStream = null;
192
193 try {
194 ByteArrayOutputStream outputStream = new ByteArrayOutputStream ( 2048 );
195 serializer.setOutputStream( outputStream );
196 toSAX( serializer );
197 inputStream = new ByteArrayInputStream ( outputStream.toByteArray() );
198 } catch ( SAXException se ) {
199 logger.error( "SAX exception!", se );
200 throw new SourceException( "Serializing SAX to a ByteArray failed!", se );
201 }
202
203 return inputStream;
204 }
205
206
212 public boolean exists() {
213 boolean exists = false;
214 try {
215 exists = getInputAttribute( this.attributeType, this.attributeName ) != null;
216 } catch ( SAXException e ) {
217 exists = false;
218 }
219 return exists;
220 }
221
222
229 public OutputStream getOutputStream() throws IOException {
230 return new DOMOutputStream();
231 }
232
233
236 public void delete() throws SourceException {
237 if ( !(this.xPath.length() == 0 || this.xPath.equals( "/" )) ) {
238 Object value;
239 try {
240 value = getInputAttribute( this.attributeType, this.attributeName );
241 } catch ( SAXException e ) {
242 throw new SourceException( "delete: ", e );
243 }
244 if ( value == null )
245 throw new SourceException( " The attribute: " + this.attributeName +
246 " is empty" );
247
248 JXPathContext context = JXPathContext.newContext( value );
249 context.removeAll( this.xPath );
250 } else {
251 try {
252 setOutputAttribute( this.attributeType, this.attributeName, null );
253 } catch ( SAXException e ) {
254 throw new SourceException( "delete: ", e );
255 }
256 }
257 }
258
259
264 public void deleteTest() throws SourceException {
265 delete();
266 }
267
268
274 public boolean canCancel( OutputStream stream ) { return false; }
275
276
282 public void cancel(OutputStream stream) throws IOException {}
283
284
294 public ContentHandler getContentHandler() {
295 return new DOMBuilder( this );
296 }
297
298 public void notify( Document insertDoc ) throws SAXException {
299
300 if ( !(this.xPath.length() == 0 || this.xPath.equals( "/" )) ) {
303
304 Object value = getInputAttribute( this.attributeType, this.attributeName );
305 if ( value == null )
306 throw new SAXException ( " The attribute: " + this.attributeName +
307 " is empty" );
308
309 JXPathContext context = JXPathContext.newContext( value );
310
311 if ( value instanceof Document ) {
312 Document doc = (Document )value;
317
318 Node importedNode =
319 doc.importNode( insertDoc.getDocumentElement(), true );
320
321 context.setLenient( true );
322 context.setFactory( new DOMFactory() );
323 context.createPathAndSetValue( this.xPath, importedNode );
324 } else {
325 context.setValue( this.xPath, insertDoc );
328 }
329
330 } else {
331 setOutputAttribute( this.attributeType, this.attributeName, insertDoc );
332 }
333 }
334
335 private class DOMOutputStream extends ByteArrayOutputStream {
336 public void close() throws IOException {
337 SAXParser parser = null;
338 try {
339 parser = (SAXParser)XModuleSource.this.manager.lookup( SAXParser.ROLE );
340
341 parser.parse( new InputSource ( new ByteArrayInputStream ( super.toByteArray() ) ),
342 XModuleSource.this.getContentHandler());
343 } catch (Exception e){
344 throw new IOException ("Exception during processing of " +
345 XModuleSource.super.getURI() +
346 e.getMessage());
347 } finally {
348 if (parser != null) XModuleSource.this.manager.release( parser );
349 }
350 super.close();
351 }
352 }
353
354
355 private Object getInputAttribute( String inputModuleName, String attributeName )
356 throws SAXException {
357 Object obj;
358 ServiceSelector selector = null;
359 InputModule inputModule = null;
360 try {
361 selector = (ServiceSelector) this.manager.lookup( InputModule.ROLE + "Selector" );
362 inputModule = (InputModule) selector.select( inputModuleName );
363 obj = inputModule.getAttribute( attributeName, null, this.objectModel );
364
365 } catch ( ServiceException e ) {
366 throw new SAXException ( "Could not find an InputModule of the type " +
367 inputModuleName , e );
368 } catch ( ConfigurationException e ) {
369 throw new SAXException ( "Could not find an attribute: " + attributeName +
370 " from the InputModule " + inputModuleName, e );
371 } finally {
372 if ( inputModule != null ) selector.release( inputModule );
373 this.manager.release( selector );
374 }
375
376 return obj;
377 }
378
379 private void setOutputAttribute( String outputModuleName,
380 String attributeName, Object value )
381 throws SAXException {
382 ServiceSelector selector = null;
383 OutputModule outputModule = null;
384 try {
385 selector = (ServiceSelector) this.manager.lookup( OutputModule.ROLE + "Selector" );
386 outputModule = (OutputModule) selector.select( outputModuleName );
387 outputModule.setAttribute( null, this.objectModel, attributeName, value );
388 outputModule.commit( null, this.objectModel );
389
390 } catch ( ServiceException e ) {
391 throw new SAXException ( "Could not find an OutputModule of the type " +
392 outputModuleName , e );
393 } finally {
394 if ( outputModule != null ) selector.release( outputModule );
395 this.manager.release( selector );
396 }
397 }
398 }
399 |
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