| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You 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.transformation; |
| |
| import java.io.IOException; |
| import java.util.HashMap; |
| import java.util.Iterator; |
| import java.util.Map; |
| |
| import org.apache.avalon.framework.parameters.Parameters; |
| |
| import org.apache.cocoon.ProcessingException; |
| import org.apache.cocoon.environment.SourceResolver; |
| import org.apache.cocoon.xml.dom.DOMBuilder; |
| |
| import org.w3c.dom.Document; |
| import org.xml.sax.Attributes; |
| import org.xml.sax.SAXException; |
| |
| |
| /** |
| * This transformer sieves an incoming stream of xml |
| * and feeds a DOMBuilder with it. |
| * |
| * @author <a href="mailto:paul@luminas.co.uk">Paul Russell</a> |
| * @author <a href="mailto:haul@apache.org">Christian Haul</a> |
| * @version CVS $Id$ |
| */ |
| abstract public class AbstractExtractionTransformer extends AbstractTransformer { |
| |
| protected DOMBuilder currentBuilder; |
| |
| private Map prefixMap; |
| |
| protected int extractLevel; |
| |
| |
| /** Setup the transformer. */ |
| public void setup(SourceResolver resolver, Map objectModel, String src, Parameters parameters) |
| throws ProcessingException, SAXException, IOException { |
| extractLevel = 0; |
| prefixMap = new HashMap(); |
| } |
| |
| public void recycle() { |
| this.extractLevel = 0; |
| this.currentBuilder = null; |
| this.prefixMap = null; |
| super.recycle(); |
| } |
| |
| |
| /** |
| * Begin the scope of a prefix-URI Namespace mapping. |
| * |
| * @param prefix The Namespace prefix being declared. |
| * @param uri The Namespace URI the prefix is mapped to. |
| */ |
| public void startPrefixMapping(String prefix, String uri) |
| throws SAXException { |
| if (extractLevel == 0) { |
| super.startPrefixMapping(prefix,uri); |
| prefixMap.put(prefix,uri); |
| } else { |
| this.currentBuilder.startPrefixMapping(prefix,uri); |
| } |
| } |
| |
| /** |
| * End the scope of a prefix-URI mapping. |
| * |
| * @param prefix The prefix that was being mapping. |
| */ |
| public void endPrefixMapping(String prefix) |
| throws SAXException { |
| if (extractLevel == 0) { |
| super.endPrefixMapping(prefix); |
| prefixMap.remove(prefix); |
| } else { |
| this.currentBuilder.endPrefixMapping(prefix); |
| } |
| } |
| |
| |
| /** |
| * Receive notification of the beginning of an element. Uses |
| * startExtraction to determine whether to start |
| * extracting. Nested triggering tags result in only one document. |
| * * startExtractedDocument with the first node of the extracted |
| * Document. |
| * |
| * @param uri The Namespace URI, or the empty string if the element has no |
| * Namespace URI or if Namespace |
| * processing is not being performed. |
| * @param loc The local name (without prefix), or the empty string if |
| * Namespace processing is not being performed. |
| * @param raw The raw XML 1.0 name (with prefix), or the empty string if |
| * raw names are not available. |
| * @param a The attributes attached to the element. If there are no |
| * attributes, it shall be an empty Attributes object. |
| */ |
| public void startElement(String uri, String loc, String raw, Attributes a) throws SAXException { |
| if (!startExtracting(uri, loc, raw, a)) { |
| |
| if (extractLevel == 0) { |
| super.startElement(uri,loc,raw,a); |
| } else { |
| this.currentBuilder.startElement(uri,loc,raw,a); |
| } |
| |
| } else { |
| |
| extractLevel++; |
| if (this.getLogger().isDebugEnabled()) { |
| getLogger().debug("extractLevel now " + extractLevel + "."); |
| } |
| |
| if (extractLevel != 1) { |
| this.currentBuilder.startElement(uri,loc,raw,a); |
| } else { |
| |
| // setup new document |
| this.currentBuilder = new DOMBuilder(); |
| this.currentBuilder.startDocument(); |
| // setup namespaces |
| Iterator itt = prefixMap.entrySet().iterator(); |
| while (itt.hasNext()) { |
| Map.Entry entry = (Map.Entry)itt.next(); |
| this.currentBuilder.startPrefixMapping( |
| (String)entry.getKey(), |
| (String)entry.getValue() |
| ); |
| } |
| // start root node |
| startExtractingDocument(uri, loc, raw, a); |
| |
| } |
| |
| } |
| } |
| |
| |
| /** |
| * Receive notification of the end of an element. Uses |
| * endExtraction to determine whether to stop extracting or |
| * not. Calls endExtractedDocument with the extracted document. |
| * |
| * @param uri The Namespace URI, or the empty string if the element has no |
| * Namespace URI or if Namespace |
| * processing is not being performed. |
| * @param loc The local name (without prefix), or the empty string if |
| * Namespace processing is not being performed. |
| * @param raw The raw XML 1.0 name (with prefix), or the empty string if |
| * raw names are not available. |
| */ |
| public void endElement(String uri, String loc, String raw) |
| throws SAXException { |
| if (extractLevel == 0) { |
| super.endElement(uri,loc,raw); |
| } else { |
| if (endExtracting(uri, loc, raw)) { |
| extractLevel--; |
| if (this.getLogger().isDebugEnabled()) { |
| getLogger().debug("extractLevel now " + extractLevel + "."); |
| } |
| |
| if (extractLevel != 0) { |
| this.currentBuilder.endElement(uri,loc,raw); |
| } else { |
| |
| // end root element |
| endExtractingDocument(uri, loc, raw); |
| // finish building the document. remove existing prefix mappings. |
| Iterator itt = prefixMap.entrySet().iterator(); |
| while (itt.hasNext()) { |
| Map.Entry entry = (Map.Entry) itt.next(); |
| this.currentBuilder.endPrefixMapping( |
| (String)entry.getKey() |
| ); |
| } |
| this.currentBuilder.endDocument(); |
| |
| handleExtractedDocument(this.currentBuilder.getDocument()); |
| |
| if (this.getLogger().isDebugEnabled()) { |
| getLogger().debug("Stored document."); |
| } |
| |
| } |
| } else { |
| this.currentBuilder.endElement(uri, loc, raw); |
| } |
| } |
| } |
| |
| /** |
| * Receive notification of character data. |
| * |
| * @param c The characters from the XML document. |
| * @param start The start position in the array. |
| * @param len The number of characters to read from the array. |
| */ |
| public void characters(char c[], int start, int len) |
| throws SAXException { |
| if (extractLevel == 0) { |
| super.characters(c,start,len); |
| } else { |
| this.currentBuilder.characters(c,start,len); |
| } |
| } |
| |
| /** |
| * Receive notification of ignorable whitespace in element content. |
| * |
| * @param c The characters from the XML document. |
| * @param start The start position in the array. |
| * @param len The number of characters to read from the array. |
| */ |
| public void ignorableWhitespace(char c[], int start, int len) |
| throws SAXException { |
| if (extractLevel == 0) { |
| super.ignorableWhitespace(c,start,len); |
| } else { |
| this.currentBuilder.ignorableWhitespace(c,start,len); |
| } |
| } |
| |
| /** |
| * Receive notification of a processing instruction. |
| * |
| * @param target The processing instruction target. |
| * @param data The processing instruction data, or null if none was |
| * supplied. |
| */ |
| public void processingInstruction(String target, String data) |
| throws SAXException { |
| if (extractLevel == 0) { |
| super.processingInstruction(target,data); |
| } else { |
| this.currentBuilder.processingInstruction(target,data); |
| } |
| } |
| |
| /** |
| * Receive notification of a skipped entity. |
| * |
| * @param name The name of the skipped entity. If it is a parameter |
| * entity, the name will begin with '%'. |
| */ |
| public void skippedEntity(String name) |
| throws SAXException { |
| if (extractLevel == 0) { |
| super.skippedEntity(name); |
| } else { |
| this.currentBuilder.skippedEntity(name); |
| } |
| } |
| |
| /** |
| * Report the start of DTD declarations, if any. |
| * |
| * @param name The document type name. |
| * @param publicId The declared public identifier for the external DTD |
| * subset, or null if none was declared. |
| * @param systemId The declared system identifier for the external DTD |
| * subset, or null if none was declared. |
| */ |
| public void startDTD(String name, String publicId, String systemId) |
| throws SAXException { |
| if (extractLevel == 0) { |
| super.startDTD(name,publicId,systemId); |
| } else { |
| throw new SAXException( |
| "Recieved startDTD after beginning fragment extraction process." |
| ); |
| } |
| } |
| |
| /** |
| * Report the end of DTD declarations. |
| */ |
| public void endDTD() |
| throws SAXException { |
| if (extractLevel == 0) { |
| super.endDTD(); |
| } else { |
| throw new SAXException( |
| "Recieved endDTD after beginning fragment extraction process." |
| ); |
| } |
| } |
| |
| /** |
| * Report the beginning of an entity. |
| * |
| * @param name The name of the entity. If it is a parameter entity, the |
| * name will begin with '%'. |
| */ |
| public void startEntity(String name) |
| throws SAXException { |
| if (extractLevel == 0) { |
| super.startEntity(name); |
| } else { |
| this.currentBuilder.startEntity(name); |
| } |
| } |
| |
| /** |
| * Report the end of an entity. |
| * |
| * @param name The name of the entity that is ending. |
| */ |
| public void endEntity(String name) |
| throws SAXException { |
| if (extractLevel == 0) { |
| super.endEntity(name); |
| } else { |
| this.currentBuilder.endEntity(name); |
| } |
| } |
| |
| /** |
| * Report the start of a CDATA section. |
| */ |
| public void startCDATA() |
| throws SAXException { |
| if (extractLevel == 0) { |
| super.startCDATA(); |
| } else { |
| this.currentBuilder.startCDATA(); |
| } |
| } |
| |
| /** |
| * Report the end of a CDATA section. |
| */ |
| public void endCDATA() |
| throws SAXException { |
| if (extractLevel == 0) { |
| super.endCDATA(); |
| } else { |
| this.currentBuilder.endCDATA(); |
| } |
| } |
| |
| /** |
| * Report an XML comment anywhere in the document. |
| * |
| * @param ch An array holding the characters in the comment. |
| * @param start The starting position in the array. |
| * @param len The number of characters to use from the array. |
| */ |
| public void comment(char ch[], int start, int len) |
| throws SAXException { |
| if (extractLevel == 0) { |
| super.comment(ch,start,len); |
| } else { |
| this.currentBuilder.comment(ch,start,len); |
| } |
| } |
| |
| |
| |
| /** |
| * Receive notification of the beginning of an element and signal extraction start. |
| * |
| * @param uri The Namespace URI, or the empty string if the element has no |
| * Namespace URI or if Namespace |
| * processing is not being performed. |
| * @param loc The local name (without prefix), or the empty string if |
| * Namespace processing is not being performed. |
| * @param raw The raw XML 1.0 name (with prefix), or the empty string if |
| * raw names are not available. |
| * @param a The attributes attached to the element. If there are no |
| * attributes, it shall be an empty Attributes object. |
| * @return a <code>boolean</code> value to signal to start extracting |
| */ |
| abstract boolean startExtracting(String uri, String loc, String raw, Attributes a); |
| |
| /** |
| * Receive notification of the beginning of the extracted Document. Per default send |
| * startElement message to document builder. Override if necessary. Must override |
| * {@link #endExtractingDocument(String, String, String)} as well. |
| * |
| * @param uri The Namespace URI, or the empty string if the element has no |
| * Namespace URI or if Namespace |
| * processing is not being performed. |
| * @param loc The local name (without prefix), or the empty string if |
| * Namespace processing is not being performed. |
| * @param raw The raw XML 1.0 name (with prefix), or the empty string if |
| * raw names are not available. |
| * @param a The attributes attached to the element. If there are no |
| * attributes, it shall be an empty Attributes object. |
| */ |
| public void startExtractingDocument(String uri, String loc, String raw, Attributes a) throws SAXException{ |
| this.currentBuilder.startElement(uri,loc,raw,a); |
| } |
| |
| /** |
| * Receive notification of the end of an element and signal extraction end. |
| * |
| * @param uri The Namespace URI, or the empty string if the element has no |
| * Namespace URI or if Namespace |
| * processing is not being performed. |
| * @param loc The local name (without prefix), or the empty string if |
| * Namespace processing is not being performed. |
| * @param raw The raw XML 1.0 name (with prefix), or the empty string if |
| * @return a <code>boolean</code> value to signal to stop extracting |
| */ |
| abstract boolean endExtracting(String uri, String loc, String raw); |
| |
| /** |
| * Receive notification of the end of the extracted Document. Per default, |
| * send endElement message to document builder. Override if necessary. |
| * Must override |
| * {@link #startExtractingDocument(String, String, String, Attributes)} |
| * as well. |
| * |
| * @param uri The Namespace URI, or the empty string if the element has no |
| * Namespace URI or if Namespace |
| * processing is not being performed. |
| * @param loc The local name (without prefix), or the empty string if |
| * Namespace processing is not being performed. |
| * @param raw The raw XML 1.0 name (with prefix), or the empty string if |
| * raw names are not available. |
| */ |
| public void endExtractingDocument(String uri, String loc, String raw) throws SAXException{ |
| this.currentBuilder.endElement(uri,loc,raw); |
| } |
| |
| /** |
| * Receive notification of the end of the extracted Document. |
| * |
| * @param doc a <code>Document</code> value |
| */ |
| abstract void handleExtractedDocument(Document doc); |
| |
| |
| } |
