package org.apache.velocity.runtime.log;
/*
* 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.
*/
import java.io.IOException;
import java.lang.reflect.Field;
import org.apache.log4j.Level;
import org.apache.log4j.Logger;
import org.apache.log4j.PatternLayout;
import org.apache.log4j.RollingFileAppender;
import org.apache.velocity.runtime.RuntimeConstants;
import org.apache.velocity.runtime.RuntimeServices;
import org.apache.velocity.util.ExceptionUtils;
/**
* Implementation of a simple log4j system that will either latch onto
* an existing category, or just do a simple rolling file log.
*
* @author <a href="mailto:geirm@apache.org>Geir Magnusson Jr.</a>
* @author <a href="mailto:dlr@finemaltcoding.com>Daniel L. Rall</a>
* @author <a href="mailto:nbubna@apache.org>Nathan Bubna</a>
* @version $Id: Log4JLogChute.java 463298 2006-10-12 16:10:32Z henning $
* @since Velocity 1.5
*/
public class Log4JLogChute implements LogChute
{
/**
*
*/
public static final String RUNTIME_LOG_LOG4J_LOGGER =
"runtime.log.logsystem.log4j.logger";
private RuntimeServices rsvc = null;
private boolean hasTrace = false;
private RollingFileAppender appender = null;
/**
* <a href="http://jakarta.apache.org/log4j/">Log4J</a> logging API.
*/
protected Logger logger = null;
/**
* @see org.apache.velocity.runtime.log.LogChute#init(org.apache.velocity.runtime.RuntimeServices)
*/
public void init(RuntimeServices rs) throws Exception
{
rsvc = rs;
/* first see if there is a category specified and just use that - it allows
* the application to make us use an existing logger
*/
String name = (String)rsvc.getProperty(RUNTIME_LOG_LOG4J_LOGGER);
if (name != null)
{
logger = Logger.getLogger(name);
log(DEBUG_ID, "Log4JLogChute using logger '" + name + '\'');
}
else
{
// create a logger with this class name to avoid conflicts
logger = Logger.getLogger(this.getClass().getName());
// if we have a file property, then create a separate
// rolling file log for velocity messages only
String file = rsvc.getString(RuntimeConstants.RUNTIME_LOG);
if (file != null && file.length() > 0)
{
initAppender(file);
}
}
/* Ok, now let's see if this version of log4j supports the trace level. */
try
{
Field traceLevel = Level.class.getField("TRACE");
// we'll never get here in pre 1.2.12 log4j
hasTrace = true;
}
catch (NoSuchFieldException e)
{
log(DEBUG_ID,
"The version of log4j being used does not support the \"trace\" level.");
}
}
// This tries to create a file appender for the specified file name.
private void initAppender(String file) throws Exception
{
try
{
// to add the appender
PatternLayout layout = new PatternLayout("%d - %m%n");
this.appender = new RollingFileAppender(layout, file, true);
// if we successfully created the file appender,
// configure it and set the logger to use only it
appender.setMaxBackupIndex(1);
appender.setMaximumFileSize(100000);
// don't inherit appenders from higher in the logger heirarchy
logger.setAdditivity(false);
// this impl checks levels (by default don't include trace level)
logger.setLevel(Level.DEBUG);
logger.addAppender(appender);
log(DEBUG_ID, "Log4JLogChute initialized using file '"+file+'\'');
}
catch (IOException ioe)
{
rsvc.getLog().warn("Could not create file appender '"+file+'\'', ioe);
throw ExceptionUtils.createRuntimeException("Error configuring Log4JLogChute : ", ioe);
}
}
/**
* logs messages
*
* @param level severity level
* @param message complete error message
*/
public void log(int level, String message)
{
switch (level)
{
case LogChute.WARN_ID:
logger.warn(message);
break;
case LogChute.INFO_ID:
logger.info(message);
break;
case LogChute.DEBUG_ID:
logger.debug(message);
break;
case LogChute.TRACE_ID:
if (hasTrace)
{
logger.trace(message);
}
else
{
logger.debug(message);
}
break;
case LogChute.ERROR_ID:
logger.error(message);
break;
default:
logger.debug(message);
break;
}
}
/**
* @see org.apache.velocity.runtime.log.LogChute#log(int, java.lang.String, java.lang.Throwable)
*/
public void log(int level, String message, Throwable t)
{
switch (level)
{
case LogChute.WARN_ID:
logger.warn(message, t);
break;
case LogChute.INFO_ID:
logger.info(message, t);
break;
case LogChute.DEBUG_ID:
logger.debug(message, t);
break;
case LogChute.TRACE_ID:
if (hasTrace)
{
logger.trace(message, t);
}
else
{
logger.debug(message, t);
}
break;
case LogChute.ERROR_ID:
logger.error(message, t);
break;
default:
logger.debug(message, t);
break;
}
}
/**
* @see org.apache.velocity.runtime.log.LogChute#isLevelEnabled(int)
*/
public boolean isLevelEnabled(int level)
{
switch (level)
{
case LogChute.DEBUG_ID:
return logger.isDebugEnabled();
case LogChute.INFO_ID:
return logger.isInfoEnabled();
case LogChute.TRACE_ID:
if (hasTrace)
{
return logger.isTraceEnabled();
}
else
{
return logger.isDebugEnabled();
}
case LogChute.WARN_ID:
return logger.isEnabledFor(Level.WARN);
case LogChute.ERROR_ID:
// can't be disabled in log4j
return logger.isEnabledFor(Level.ERROR);
default:
return true;
}
}
/**
* Also do a shutdown if the object is destroy()'d.
* @throws Throwable
*/
protected void finalize() throws Throwable
{
shutdown();
}
/** Close all destinations*/
public void shutdown()
{
if (appender != null)
{
logger.removeAppender(appender);
appender.close();
appender = null;
}
}
}