/*******************************************************************************
* This file is part of the Symfony eclipse plugin.
*
* (c) Robert Gruendler <r.gruendler@gmail.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
******************************************************************************/
package com.dubture.symfony.core.parser;
import java.io.IOException;
import java.io.InputStream;
import java.util.Stack;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.xml.sax.Attributes;
import org.xml.sax.Locator;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;
/**
* @see http
* ://stackoverflow.com/questions/4915422/get-line-number-from-xml-node-
* java
*/
public class PositionalXMLReader
{
final static String LINE_NUMBER_KEY_NAME = "lineNumber";
public static Document readXML(final InputStream is) throws IOException,
SAXException
{
final Document doc;
SAXParser parser;
try {
final SAXParserFactory factory = SAXParserFactory.newInstance();
parser = factory.newSAXParser();
final DocumentBuilderFactory docBuilderFactory = DocumentBuilderFactory
.newInstance();
final DocumentBuilder docBuilder = docBuilderFactory
.newDocumentBuilder();
doc = docBuilder.newDocument();
} catch (final ParserConfigurationException e) {
throw new RuntimeException(
"Can't create SAX parser / DOM builder.", e);
}
final Stack<Element> elementStack = new Stack<Element>();
final StringBuilder textBuffer = new StringBuilder();
final DefaultHandler handler = new DefaultHandler()
{
private Locator locator;
@Override
public void setDocumentLocator(final Locator locator)
{
this.locator = locator; // Save the locator, so that it can be
// used later for line tracking when
// traversing nodes.
}
@Override
public void startElement(final String uri, final String localName,
final String qName, final Attributes attributes)
throws SAXException
{
addTextIfNeeded();
final Element el = doc.createElement(qName);
for (int i = 0; i < attributes.getLength(); i++) {
el.setAttribute(attributes.getQName(i),
attributes.getValue(i));
}
el.setUserData(LINE_NUMBER_KEY_NAME,
String.valueOf(this.locator.getLineNumber()), null);
elementStack.push(el);
}
@Override
public void endElement(final String uri, final String localName,
final String qName)
{
addTextIfNeeded();
final Element closedEl = elementStack.pop();
if (elementStack.isEmpty()) { // Is this the root element?
doc.appendChild(closedEl);
} else {
final Element parentEl = elementStack.peek();
parentEl.appendChild(closedEl);
}
}
@Override
public void characters(final char ch[], final int start,
final int length) throws SAXException
{
textBuffer.append(ch, start, length);
}
// Outputs text accumulated under the current node
private void addTextIfNeeded()
{
if (textBuffer.length() > 0) {
final Element el = elementStack.peek();
final Node textNode = doc.createTextNode(textBuffer
.toString());
el.appendChild(textNode);
textBuffer.delete(0, textBuffer.length());
}
}
};
parser.parse(is, handler);
return doc;
}
}