com.mchange.v2.util.XmlProperties Maven / Gradle / Ivy
/*
* Distributed as part of mchange-commons-java 0.2.11
*
* Copyright (C) 2015 Machinery For Change, Inc.
*
* Author: Steve Waldman
*
* This library is free software; you can redistribute it and/or modify
* it under the terms of EITHER:
*
* 1) The GNU Lesser General Public License (LGPL), version 2.1, as
* published by the Free Software Foundation
*
* OR
*
* 2) The Eclipse Public License (EPL), version 1.0
*
* You may choose which license to accept if you wish to redistribute
* or modify this work. You may offer derivatives of this work
* under the license you have chosen, or you may provide the same
* choice of license which you have been offered here.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
*
* You should have received copies of both LGPL v2.1 and EPL v1.0
* along with this software; see the files LICENSE-EPL and LICENSE-LGPL.
* If not, the text of these licenses are currently available at
*
* LGPL v2.1: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html
* EPL v1.0: http://www.eclipse.org/org/documents/epl-v10.php
*
*/
package com.mchange.v2.util;
import java.io.*;
import java.util.*;
import javax.xml.parsers.*;
import javax.xml.transform.*;
import javax.xml.transform.dom.*;
import javax.xml.transform.stream.*;
import org.w3c.dom.*;
import org.xml.sax.*;
//Example Document:
//
//
//
//
//
//
// This is the first value.
// Spaced Label:
// Whatever.
// ]]>
//
public class XmlProperties extends Properties
{
final static String DTD_SYSTEM_ID = "http://www.mchange.com/dtd/xml-properties.dtd";
final static String DTD_RSRC_PATH = "dtd/xml-properties.dtd";
//MT: members not thread-safe, but access protected by this' lock
DocumentBuilder docBuilder;
Transformer identityTransformer;
public XmlProperties() throws ParserConfigurationException, TransformerConfigurationException
{
EntityResolver er = new EntityResolver()
{
public InputSource resolveEntity (String publicId, String systemId)
{
if (DTD_SYSTEM_ID.equals( systemId ))
{
InputStream is = XmlProperties.class.getResourceAsStream(DTD_RSRC_PATH);
return new InputSource(is);
}
else return null;
}
};
ErrorHandler eh = new ErrorHandler()
{
public void warning(SAXParseException e) throws SAXException
{ System.err.println("[Warning] " + e.toString()); }
public void error(SAXParseException e) throws SAXException
{ System.err.println("[Error] " + e.toString()); }
public void fatalError(SAXParseException e) throws SAXException
{ System.err.println("[Fatal Error] " + e.toString()); }
};
DocumentBuilderFactory dbFact = DocumentBuilderFactory.newInstance();
dbFact.setValidating( true );
dbFact.setCoalescing( true );
dbFact.setIgnoringComments( true );
this.docBuilder = dbFact.newDocumentBuilder();
this.docBuilder.setEntityResolver( er );
this.docBuilder.setErrorHandler( eh );
TransformerFactory tFact = TransformerFactory.newInstance();
this.identityTransformer = tFact.newTransformer();
this.identityTransformer.setOutputProperty("indent", "yes");
this.identityTransformer.setOutputProperty("doctype-system", DTD_SYSTEM_ID);
}
public synchronized void loadXml(InputStream is) throws IOException, SAXException
{
Document doc = docBuilder.parse( is );
NodeList nl = doc.getElementsByTagName("property");
for( int i = 0, len = nl.getLength(); i < len; ++i)
extractProperty( nl.item( i ) );
}
/*
* This method presumes validation by our DTD and a coalescing,
* comment-ignoring parser!
*/
private void extractProperty( Node propNode )
{
Element propElem = (Element) propNode;
String key = propElem.getAttribute( "name" );
boolean trim = Boolean.valueOf( propElem.getAttribute("trim") ).booleanValue();
NodeList nl = propElem.getChildNodes();
int len = nl.getLength();
assert (len >= 0 && len <= 1) : "Bad number of children of property element: " + len;
String val = ( len == 0 ? "" : ((Text) nl.item(0)).getNodeValue() );
if (trim)
val = val.trim();
this.put( key, val );
}
public synchronized void saveXml(OutputStream os)
throws IOException, TransformerException
{ storeXml( os, null ); }
public synchronized void storeXml(OutputStream os, String header)
throws IOException, TransformerException
{
Document doc = docBuilder.newDocument();
if (header != null)
{
Comment comment = doc.createComment( header );
doc.appendChild( comment );
}
Element xmlPropsElem = doc.createElement("xml-properties");
for( Iterator ii = this.keySet().iterator(); ii.hasNext(); )
{
Element propsElem = doc.createElement("property");
String key = (String) ii.next();
String val = (String) this.get(key);
propsElem.setAttribute( "name", key );
Text valNode = doc.createTextNode(val);
propsElem.appendChild( valNode );
xmlPropsElem.appendChild( propsElem );
}
doc.appendChild( xmlPropsElem );
identityTransformer.transform( new DOMSource( doc ), new StreamResult( os ) );
}
public static void main( String[] argv )
{
InputStream is = null;
OutputStream os = null;
try
{
is = new BufferedInputStream( new FileInputStream( argv[0] ) );
os = new BufferedOutputStream( new FileOutputStream( argv[1] ) );
XmlProperties xmlProps = new XmlProperties();
xmlProps.loadXml( is );
xmlProps.list( System.out );
xmlProps.storeXml( os, "This is the resaved test document." );
os.flush();
}
catch ( Exception e )
{ e.printStackTrace(); }
finally
{
try { if (is != null) is.close(); } catch (Exception e) { e.printStackTrace(); }
try { if (os != null) os.close(); } catch (Exception e) { e.printStackTrace(); }
}
}
}