| /* |
| * Copyright 1999-2004 The Apache Software Foundation. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.cocoon.generation; |
| |
| import java.io.Serializable; |
| |
| import org.apache.avalon.framework.service.ServiceException; |
| import org.apache.cocoon.ResourceNotFoundException; |
| import org.apache.cocoon.ProcessingException; |
| import org.apache.cocoon.caching.CacheableProcessingComponent; |
| import org.apache.cocoon.components.sax.XMLByteStreamInterpreter; |
| |
| import org.apache.excalibur.source.SourceValidity; |
| import org.apache.excalibur.source.impl.validity.NOPValidity; |
| import org.apache.excalibur.store.Store; |
| |
| import org.xml.sax.SAXException; |
| |
| /** |
| * The generation half of FragmentExtractor. |
| * |
| * FragmentExtractor is a transformer-generator pair which is designed to allow |
| * sitemap managers to extract certain nodes from a SAX stream and move them |
| * into a separate pipeline. The main use for this is to extract inline SVG |
| * images and serve them up through a separate pipeline, usually serializing |
| * them to PNG or JPEG format first. |
| * |
| * This is by no means complete yet, but it should prove useful, particularly |
| * for offline generation. |
| * |
| * @version $Id$ |
| */ |
| public class FragmentExtractorGenerator extends ServiceableGenerator |
| implements CacheableProcessingComponent { |
| |
| /** |
| * Generate the unique key. |
| * This key must be unique inside the space of this component. |
| * |
| * @return The generated key hashes the src |
| */ |
| public Serializable getKey() { |
| return this.source; |
| } |
| |
| /** |
| * Generate the validity object. |
| * |
| * @return The generated validity object or <code>null</code> if the |
| * component is currently not cacheable. |
| */ |
| public SourceValidity getValidity() { |
| return NOPValidity.SHARED_INSTANCE; |
| } |
| |
| public void generate() throws SAXException, ProcessingException { |
| // Obtain the fragmentID (which is simply the filename portion of the source) |
| if (getLogger().isDebugEnabled()) { |
| getLogger().debug("Retrieving fragment " + source + "."); |
| } |
| |
| Store store = null; |
| Object fragment = null; |
| try { |
| store = (Store) this.manager.lookup(Store.TRANSIENT_STORE); |
| fragment = store.get(source); |
| if (fragment == null) { |
| throw new ResourceNotFoundException("Could not find fragment " + source + " in store"); |
| } |
| |
| XMLByteStreamInterpreter deserializer = new XMLByteStreamInterpreter(); |
| deserializer.setConsumer(this.xmlConsumer); |
| deserializer.deserialize(fragment); |
| |
| } catch (ServiceException ce) { |
| if (getLogger().isDebugEnabled()) { |
| getLogger().debug("Could not lookup for component.", ce); |
| } |
| throw new SAXException("Could not lookup for component.", ce); |
| } finally { |
| this.manager.release(store); |
| } |
| } |
| } |