/*
* 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: XMPSerializer.java 426584 2006-07-28 16:01:47Z jeremias $ */
package org.apache.xmlgraphics.xmp;
import java.io.OutputStream;
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.SAXTransformerFactory;
import javax.xml.transform.sax.TransformerHandler;
import javax.xml.transform.stream.StreamResult;
import org.xml.sax.SAXException;
/**
* Serializes an XMP tree to XML or to an XMP packet.
*/
public class XMPSerializer {
private static final String DEFAULT_ENCODING = "UTF-8";
/**
* Writes the in-memory representation of the XMP metadata to a JAXP Result.
* @param meta the metadata
* @param res the JAXP Result to write to
* @throws TransformerConfigurationException if an error occurs setting up the XML
* infrastructure.
* @throws SAXException if a SAX-related problem occurs while writing the XML
*/
public static void writeXML(Metadata meta, Result res)
throws TransformerConfigurationException, SAXException {
writeXML(meta, res, false, false);
}
/**
* Writes the in-memory representation of the XMP metadata to an OutputStream as an XMP packet.
* @param meta the metadata
* @param out the stream to write to
* @param readOnlyXMP true if the generated XMP packet should be read-only
* @throws TransformerConfigurationException if an error occurs setting up the XML
* infrastructure.
* @throws SAXException if a SAX-related problem occurs while writing the XML
*/
public static void writeXMPPacket(Metadata meta, OutputStream out, boolean readOnlyXMP)
throws TransformerConfigurationException, SAXException {
StreamResult res = new StreamResult(out);
writeXML(meta, res, true, readOnlyXMP);
}
private static void writeXML(Metadata meta, Result res,
boolean asXMPPacket, boolean readOnlyXMP)
throws TransformerConfigurationException, SAXException {
SAXTransformerFactory tFactory = (SAXTransformerFactory)SAXTransformerFactory.newInstance();
TransformerHandler handler = tFactory.newTransformerHandler();
Transformer transformer = handler.getTransformer();
if (asXMPPacket) {
transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");
}
transformer.setOutputProperty(OutputKeys.ENCODING, DEFAULT_ENCODING);
transformer.setOutputProperty(OutputKeys.INDENT, "yes");
handler.setResult(res);
handler.startDocument();
if (asXMPPacket) {
handler.processingInstruction("xpacket",
"begin=\"\uFEFF\" id=\"W5M0MpCehiHzreSzNTczkc9d\"");
}
meta.toSAX(handler);
if (asXMPPacket) {
if (readOnlyXMP) {
handler.processingInstruction("xpacket", "end=\"r\"");
} else {
//Create padding string (40 * 101 characters is more or less the recommended 4KB)
StringBuffer sb = new StringBuffer(101);
sb.append('\n');
for (int i = 0; i < 100; i++) {
sb.append(" ");
}
char[] padding = sb.toString().toCharArray();
for (int i = 0; i < 40; i++) {
handler.characters(padding, 0, padding.length);
}
handler.characters(new char[] {'\n'}, 0, 1);
handler.processingInstruction("xpacket", "end=\"w\"");
}
}
handler.endDocument();
}
}