/*
* 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: IFConcatenator.java 1026003 2010-10-21 14:01:59Z jeremias $ */
package org.apache.fop.render.intermediate.util;
import java.awt.Dimension;
import javax.xml.transform.Source;
import javax.xml.transform.TransformerException;
import org.apache.xmlgraphics.xmp.Metadata;
import org.apache.fop.render.intermediate.IFDocumentHandler;
import org.apache.fop.render.intermediate.IFDocumentNavigationHandler;
import org.apache.fop.render.intermediate.IFException;
import org.apache.fop.render.intermediate.IFParser;
/**
* This class allows to concatenate multiple intermediate format files to a single output file
* in the final format. It is based on the SAX API and is therefore very fast and does not
* require to load the individual documents into memory as DOM documents, for example.
* <p>
* Note: This class will filter/ignore any document navigation events. Support for this may be
* added later.
* <p>
* Note: document-level extensions will only be transferred from the first document passed in.
* If you need to merge extensions from all the concatenated documents, you may have to merge
* these manually on the XML level, for example using XSLT.
*/
public class IFConcatenator {
private IFDocumentHandler targetHandler;
private int nextPageIndex = 0;
private boolean inFirstDocument = true;
/**
* Creates a new IF concatenator.
* @param targetHandler the target document handler
* @param metadata the metadata object for the generated file (may be null)
* @throws IFException if an IF-related error occurs
*/
public IFConcatenator(IFDocumentHandler targetHandler, Metadata metadata) throws IFException {
this.targetHandler = targetHandler;
startDocument(metadata);
}
private void startDocument(Metadata metadata) throws IFException {
this.targetHandler.startDocument();
this.targetHandler.startDocumentHeader();
if (metadata != null) {
this.targetHandler.handleExtensionObject(metadata);
}
this.targetHandler.endDocumentHeader();
}
private void endDocument() throws IFException {
this.targetHandler.startPageTrailer();
this.targetHandler.endPageTrailer();
this.targetHandler.endDocument();
}
/**
* Returns the target document handler.
* @return the target document handler
*/
protected IFDocumentHandler getTargetHandler() {
return this.targetHandler;
}
/**
* Properly finishes the current output file by creating an empty document trailer and calling
* {@link IFDocumentHandler#endDocument()}.
* @throws IFException if an IF-related error occurs
*/
public void finish() throws IFException {
endDocument();
}
/**
* Appends another intermediate format document to the current output file. All document-level
* content (i.e. the document header and trailer) is ignored. This method shall not be called
* after {@link #finish()} has been called.
* @param src the JAXP Source identifying the input document
* @throws TransformerException if an XML-related exception occurs during
* @throws IFException if an IF-related error occurs
*/
public void appendDocument(Source src) throws TransformerException, IFException {
IFParser parser = new IFParser();
parser.parse(src, new IFPageSequenceFilter(getTargetHandler()),
getTargetHandler().getContext().getUserAgent());
}
private class IFPageSequenceFilter extends IFDocumentHandlerProxy {
private boolean inPageSequence = false;
public IFPageSequenceFilter(IFDocumentHandler delegate) {
super(delegate);
}
/** {@inheritDoc} */
public void startDocument() throws IFException {
//ignore
}
/** {@inheritDoc} */
public void startDocumentHeader() throws IFException {
//ignore
}
/** {@inheritDoc} */
public void endDocumentHeader() throws IFException {
//ignore
}
/** {@inheritDoc} */
public void startPageSequence(String id) throws IFException {
assert !this.inPageSequence;
this.inPageSequence = true;
super.startPageSequence(id);
}
/** {@inheritDoc} */
public void startPage(int index, String name, String pageMasterName, Dimension size)
throws IFException {
//Adjust page indices
super.startPage(nextPageIndex, name, pageMasterName, size);
nextPageIndex++;
}
/** {@inheritDoc} */
public void endPageSequence() throws IFException {
super.endPageSequence();
assert this.inPageSequence;
this.inPageSequence = false;
}
/** {@inheritDoc} */
public void startDocumentTrailer() throws IFException {
//ignore
}
/** {@inheritDoc} */
public void endDocumentTrailer() throws IFException {
//ignore
}
/** {@inheritDoc} */
public void endDocument() throws IFException {
//ignore
inFirstDocument = false;
}
/** {@inheritDoc} */
public void handleExtensionObject(Object extension) throws IFException {
if (inPageSequence || inFirstDocument) {
//Only pass through when inside page-sequence
//or for the first document (for document-level extensions).
super.handleExtensionObject(extension);
}
//Note:Extensions from non-first documents are ignored!
}
/** {@inheritDoc} */
public IFDocumentNavigationHandler getDocumentNavigationHandler() {
return null; //Document Navigation is filtered!!!
}
}
}