/*
* Copyright 1999,2004-2005 The Apache Software Foundation.
*
* Licensed 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.
*/
package org.apache.log4j.xml;
import org.apache.log4j.LogManager;
import org.apache.log4j.joran.JoranConfigurator;
import org.apache.log4j.spi.LoggerRepository;
import org.w3c.dom.Element;
import org.w3c.dom.NamedNodeMap;
import org.w3c.dom.Node;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.AttributesImpl;
import org.xml.sax.helpers.DefaultHandler;
import java.net.URL;
import javax.xml.parsers.SAXParser;
// Contributors: Mark Womack
// Arun Katkere
// Curt Arnold
/**
Use this class to initialize the log4j environment using a DOM tree.
<p>The DTD is specified in <a
href="log4j.dtd"><b>log4j.dtd</b></a>.
<p>Sometimes it is useful to see how log4j is reading configuration
files. You can enable log4j internal logging by defining the
<b>log4j.debug</b> variable on the java command
line. Alternatively, set the <code>debug</code> attribute in the
<code>log4j:configuration</code> element. As in
<pre>
<log4j:configuration <b>debug="true"</b> xmlns:log4j="http://jakarta.apache.org/log4j/">
...
</log4j:configuration>
</pre>
<p>There are sample XML files included in the package.
@author Christopher Taylor
@author Ceki Gülcü
@author Anders Kristensen
@deprecated Replaced by the much more flexible {@link org.apache.log4j.joran.JoranConfigurator}.
@since 0.8.3 */
public class DOMConfigurator extends JoranConfigurator {
public static void configure(String file) {
JoranConfigurator joran = new JoranConfigurator();
joran.doConfigure(file, LogManager.getLoggerRepository());
}
public static void configure(URL url) {
JoranConfigurator joran = new JoranConfigurator();
joran.doConfigure(url, LogManager.getLoggerRepository());
}
/**
* Configure log4j using a <code>configuration</code> element.
* @param element element, may not be null.
*/
public static void configure(final Element element) {
DOMConfigurator configurator = new DOMConfigurator();
configurator.doConfigure(element, LogManager.getLoggerRepository());
}
/**
* Configure by taking in an DOM element.
* @param element configuration element, may not be null.
* @param repository logger repository.
*/
public void doConfigure(
final Element element, final LoggerRepository repository) {
ParseAction action = new DOMElementParseAction(element);
doConfigure(action, repository);
}
/**
* Class that "parses" a DOM element by replaying the
* corresponding SAX events.
*/
private static class DOMElementParseAction implements ParseAction {
private final Element element;
private final AttributesImpl attributes = new AttributesImpl();
/**
* Creates an DOMElementParser.
* @param element configuration element.
*/
public DOMElementParseAction(final Element element) {
this.element = element;
}
/**
* Generates the SAX events corresponding to the document element.
* @param parser SAX parser, ignored.
* @param handler content receiver, may not be null.
* @throws SAXException thrown on content or handling exception.
*/
public void parse(final SAXParser parser, final DefaultHandler handler)
throws SAXException {
handler.startDocument();
replay(element, handler);
handler.endDocument();
}
/**
* Generates the SAX events corresponding to the element.
*
* @param element element, may not be null.
* @param handler content handler, may not be null.
* @throws SAXException if content error.
*/
private void replay(final Element element, final DefaultHandler handler)
throws SAXException {
String localName = element.getLocalName();
String nsURI = element.getNamespaceURI();
String qName = element.getNodeName();
if (localName == null) {
localName = qName;
}
attributes.clear();
NamedNodeMap attrNodes = element.getAttributes();
int attrCount = attrNodes.getLength();
Node attr;
for (int i = 0; i < attrCount; i++) {
attr = attrNodes.item(i);
String attrQName = attr.getNodeName();
String attrName = attr.getLocalName();
if (attrName == null) {
attrName = attrQName;
}
String attrNsURI = attr.getNamespaceURI();
String attrValue = attr.getNodeValue();
attributes.addAttribute(
attrNsURI, attrName, attrQName, "#PCDATA", attrValue);
}
handler.startElement(nsURI, localName, qName, attributes);
for (
Node child = element.getFirstChild(); child != null;
child = child.getNextSibling()) {
//
// Joran only inteprets element content,
// so unnecessary to playback comments, character data, etc.
//
if (child.getNodeType() == Node.ELEMENT_NODE) {
replay((Element) child, handler);
}
}
handler.endElement(nsURI, localName, qName);
}
}
}