/* $RCSfile$
* $Author$
* $Date$
* $Revision$
*
* Copyright (C) 2003-2007 The Chemistry Development Kit (CDK) project
*
* Contact: cdk-devel@lists.sourceforge.net
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License
* as published by the Free Software Foundation; either version 2.1
* of the License, or (at your option) any later version.
* All we ask is that proper credit is given for our work, which includes
* - but is not limited to - adding the above copyright notice to the beginning
* of your source code files, and to any copyright notice that you may distribute
* with programs based on this work.
*
* This program 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. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*/
package org.openscience.cdk.tools.periodictable;
import org.openscience.cdk.tools.ILoggingTool;
import org.openscience.cdk.tools.LoggingToolFactory;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;
import java.io.IOException;
import java.io.Reader;
import java.util.ArrayList;
import java.util.List;
/**
* Reader that instantiates an XML parser and customized handler to process
* the isotope information in the CML2 isotope data file. The Reader first
* tries to instantiate a JAXP XML parser available from Sun JVM 1.4.0 and
* later. If not found it tries the Aelfred2 parser, and as last try the
* Xerces parser.
*
* @author Miguel Rojas
* @cdk.created May 8, 2005
* @cdk.module standard
* @cdk.githash
*/
class ElementPTReader {
private XMLReader parser;
private Reader input;
private static ILoggingTool logger =
LoggingToolFactory.createLoggingTool(ElementPTReader.class);
/**
* Instantiates a new reader that parses the XML from the given <code>input</code>.
*
* @param input Reader with the XML source
*/
public ElementPTReader(Reader input) {
this.init();
this.input = input;
}
private void init() {
boolean success = false;
// If JAXP is prefered (comes with Sun JVM 1.4.0 and higher)
if (!success) {
try {
javax.xml.parsers.SAXParserFactory spf = javax.xml.parsers.SAXParserFactory.newInstance();
spf.setNamespaceAware(true);
javax.xml.parsers.SAXParser saxParser = spf.newSAXParser();
parser = saxParser.getXMLReader();
logger.info("Using JAXP/SAX XML parser.");
success = true;
} catch (Exception exception) {
logger.warn("Could not instantiate JAXP/SAX XML reader!");
logger.debug(exception);
}
}
// Aelfred is first alternative.
if (!success) {
try {
parser = (XMLReader)this.getClass().getClassLoader().
loadClass("gnu.xml.aelfred2.XmlReader").
newInstance();
logger.info("Using Aelfred2 XML parser.");
success = true;
} catch (Exception e) {
logger.warn("Could not instantiate Aelfred2 XML reader!");
logger.debug(e);
}
}
// Xerces is second alternative
if (!success) {
try {
parser = (XMLReader)this.getClass().getClassLoader().
loadClass("org.apache.xerces.parsers.SAXParser").
newInstance();
logger.info("Using Xerces XML parser.");
success = true;
} catch (Exception e) {
logger.warn("Could not instantiate Xerces XML reader!");
logger.debug(e);
}
}
if (!success) {
logger.error("Could not instantiate any XML parser!");
}
}
/**
* Triggers the XML parsing of the data file and returns the read Isotopes.
* It turns of XML validation before parsing.
*
* @return a Vector of Isotope's. Returns an empty vector is some reading error
* occured.
*/
public List<org.openscience.cdk.tools.periodictable.PeriodicTableElement> readElements() {
List<PeriodicTableElement> elements = new ArrayList<org.openscience.cdk.tools.periodictable.PeriodicTableElement>();
try {
parser.setFeature("http://xml.org/sax/features/validation", false);
logger.info("Deactivated validation");
} catch (SAXException exception) {
logger.warn("Cannot deactivate validation: ", exception.getMessage());
logger.debug(exception);
}
ElementPTHandler handler = new org.openscience.cdk.tools.periodictable.ElementPTHandler();
parser.setContentHandler(handler);
try {
parser.parse(new InputSource(input));
elements = handler.getElements();
} catch (IOException exception) {
logger.error("IOException: ", exception.getMessage());
logger.debug(exception);
} catch (SAXException saxe) {
logger.error("SAXException: ", saxe.getClass().getName());
logger.error(saxe.getMessage());
logger.debug(saxe);
}
return elements;
}
}