/*
* 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.
*/
/* $Id: AbstractXMLWritingIFDocumentHandler.java 820672 2009-10-01 14:48:27Z jeremias $ */
package org.apache.fop.render.intermediate;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.Result;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerConfigurationException;
import javax.xml.transform.sax.SAXResult;
import javax.xml.transform.sax.SAXTransformerFactory;
import javax.xml.transform.sax.TransformerHandler;
import org.xml.sax.ContentHandler;
import org.apache.fop.util.GenerationHelperContentHandler;
/**
* Abstract base class for XML-writing {@link IFDocumentHandler} implementations.
*/
public abstract class AbstractXMLWritingIFDocumentHandler extends AbstractIFDocumentHandler {
/**
* Default SAXTransformerFactory that can be used by subclasses.
*/
protected SAXTransformerFactory tFactory
= (SAXTransformerFactory)SAXTransformerFactory.newInstance();
/** Main SAX ContentHandler to receive the generated SAX events. */
protected GenerationHelperContentHandler handler;
/** {@inheritDoc} */
public void setResult(Result result) throws IFException {
if (result instanceof SAXResult) {
SAXResult saxResult = (SAXResult)result;
this.handler = new GenerationHelperContentHandler(
saxResult.getHandler(), getMainNamespace());
} else {
this.handler = new GenerationHelperContentHandler(
createContentHandler(result), getMainNamespace());
}
}
/**
* Returns the main namespace used for generated XML content.
* @return the main namespace
*/
protected abstract String getMainNamespace();
/**
* Creates a ContentHandler for the given JAXP Result instance.
* @param result the JAXP Result instance
* @return the requested SAX ContentHandler
* @throws IFException if an error occurs setting up the output
*/
protected ContentHandler createContentHandler(Result result) throws IFException {
try {
TransformerHandler tHandler = tFactory.newTransformerHandler();
Transformer transformer = tHandler.getTransformer();
transformer.setOutputProperty(OutputKeys.INDENT, "yes");
transformer.setOutputProperty(OutputKeys.METHOD, "xml");
tHandler.setResult(result);
return tHandler;
} catch (TransformerConfigurationException tce) {
throw new IFException(
"Error while setting up the serializer for XML output", tce);
}
}
}