org.apache.avalon.excalibur.logger.log4j.Log4JConfAdapter Maven / Gradle / Ivy
/*
* 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.
*/
package org.apache.avalon.excalibur.logger.log4j;
import org.apache.avalon.framework.configuration.Configurable;
import org.apache.avalon.framework.configuration.Configuration;
import org.apache.avalon.framework.configuration.ConfigurationException;
import org.apache.avalon.framework.configuration.ConfigurationUtil;
import org.apache.avalon.framework.context.Context;
import org.apache.avalon.framework.context.ContextException;
import org.apache.avalon.framework.context.Contextualizable;
import org.apache.log4j.Hierarchy;
import org.apache.log4j.Level;
import org.apache.log4j.spi.RootCategory;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
/**
* A LoggerManager for Log4j that will configure the Log4j subsystem
* using specified configuration.
*
* Note that in case of logging errors Log4J will (via the
* org.apache.log4j.helpers.LogLog class) write to System.err.
* This can be switched off but we can not substitute our
* own handler to log erros the way we prefer to do this. :-(
*
*
* So, unlike the LogKit case we have no Log4JLogger helper to
* implement and hence a different architecture: this class
* is not a helper but a regular subclass of Log4JAdapter.
*
*
* Attach PrefixDecorator and/or CachingDecorator if desired.
*
* @author Avalon Development Team
* @version CVS $Revision: 1.4 $ $Date: 2004/03/10 13:54:51 $
* @since 4.0
*/
public class Log4JConfAdapter extends Log4JAdapter
implements Configurable, Contextualizable
{
private Context m_context;
/* (non-Javadoc)
* @see org.apache.avalon.framework.context.Contextualizable#contextualize(org.apache.avalon.framework.context.Context)
*/
public void contextualize(Context context) throws ContextException
{
m_context = context;
}
/**
* This constructor creates a completely independent
* Log4J hierarchy. If you want to log to an existing
* Log4J hierarchy please use Log4JAdapter. This class
* always creates a new private hierarchy and configures
* it all by itself.
*/
public Log4JConfAdapter()
{
/**
* Copied from org.apache.log4j.LogManager.
*/
super( new Hierarchy( new RootCategory( Level.ALL ) ) );
}
/**
* Feed our configuration to Log4J.
*/
public void configure( final Configuration configuration )
throws ConfigurationException
{
final Element element = ConfigurationUtil.toElement( configuration );
final Document document = element.getOwnerDocument();
final Element newElement = document.createElement( "log4j:configuration" );
final NodeList childNodes = element.getChildNodes();
final int length = childNodes.getLength();
for( int i = 0; i < length; i++ )
{
final Node node = childNodes.item( i );
final Node newNode = node.cloneNode( true );
newElement.appendChild( newNode );
}
document.appendChild( newElement );
/**
* Copied from org.apache.log4j.xml.DomConfigurator configure().
* We want our own hierarchy to be configured, so we shall
* be a bit more elaborate then just calling configure().
*/
final Log4JConfigurator domConfigurator = new Log4JConfigurator( m_context );
domConfigurator.doConfigure( newElement, m_hierarchy );
}
}