/*
 * 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.commons.logging.impl;

import java.io.Serializable;
import org.apache.log.Logger;
import org.apache.log.Hierarchy;
import org.apache.commons.logging.Log;

Implementation of org.apache.commons.logging.Log
that wraps the avalon-logkit
logging system. Configuration of LogKit is left to the user.

LogKit accepts only String messages.
Therefore, this implementation converts object messages into strings
by called their toString() method before logging them.
Version:
$Id: LogKitLogger.java 1448119 2013-02-20 12:28:04Z tn $/**
 * Implementation of <code>org.apache.commons.logging.Log</code>
 * that wraps the <a href="http://avalon.apache.org/logkit/">avalon-logkit</a>
 * logging system. Configuration of <code>LogKit</code> is left to the user.
 * <p>
 * <code>LogKit</code> accepts only <code>String</code> messages.
 * Therefore, this implementation converts object messages into strings
 * by called their <code>toString()</code> method before logging them.
 *
 * @version $Id: LogKitLogger.java 1448119 2013-02-20 12:28:04Z tn $
 */
public class LogKitLogger implements Log, Serializable {

    
Serializable version identifier. /** Serializable version identifier. */
    private static final long serialVersionUID = 3768538055836059519L;

    // ------------------------------------------------------------- Attributes

    
Logging goes to this LogKit logger /** Logging goes to this <code>LogKit</code> logger */
    protected transient volatile Logger logger = null;

    
Name of this logger /** Name of this logger */
    protected String name = null;

    // ------------------------------------------------------------ Constructor

    
Construct LogKitLogger which wraps the LogKit
logger with given name.
Params:
name – log name/**
     * Construct <code>LogKitLogger</code> which wraps the <code>LogKit</code>
     * logger with given name.
     *
     * @param name log name
     */
    public LogKitLogger(String name) {
        this.name = name;
        this.logger = getLogger();
    }

    // --------------------------------------------------------- Public Methods

    
Return the underlying Logger we are using.
/**
     * Return the underlying Logger we are using.
     */
    public Logger getLogger() {
        Logger result = logger;
        if (result == null) {
            synchronized(this) {
                result = logger;
                if (result == null) {
                    logger = result = Hierarchy.getDefaultHierarchy().getLoggerFor(name);
                }
            }
        }
        return result;
    }

    // ----------------------------------------------------- Log Implementation

    
Logs a message with org.apache.log.Priority.DEBUG.
Params:
message – to log
See Also:
Log.trace(Object)/**
     * Logs a message with <code>org.apache.log.Priority.DEBUG</code>.
     *
     * @param message to log
     * @see org.apache.commons.logging.Log#trace(Object)
    */
    public void trace(Object message) {
        debug(message);
    }

    
Logs a message with org.apache.log.Priority.DEBUG.
Params:
message – to log
t – log this cause
See Also:
Log.trace(Object, Throwable)/**
     * Logs a message with <code>org.apache.log.Priority.DEBUG</code>.
     *
     * @param message to log
     * @param t log this cause
     * @see org.apache.commons.logging.Log#trace(Object, Throwable)
     */
    public void trace(Object message, Throwable t) {
        debug(message, t);
    }

    
Logs a message with org.apache.log.Priority.DEBUG.
Params:
message – to log
See Also:
Log.debug(Object)/**
     * Logs a message with <code>org.apache.log.Priority.DEBUG</code>.
     *
     * @param message to log
     * @see org.apache.commons.logging.Log#debug(Object)
     */
    public void debug(Object message) {
        if (message != null) {
            getLogger().debug(String.valueOf(message));
        }
    }

    
Logs a message with org.apache.log.Priority.DEBUG.
Params:
message – to log
t – log this cause
See Also:
Log.debug(Object, Throwable)/**
     * Logs a message with <code>org.apache.log.Priority.DEBUG</code>.
     *
     * @param message to log
     * @param t log this cause
     * @see org.apache.commons.logging.Log#debug(Object, Throwable)
     */
    public void debug(Object message, Throwable t) {
        if (message != null) {
            getLogger().debug(String.valueOf(message), t);
        }
    }

    
Logs a message with org.apache.log.Priority.INFO.
Params:
message – to log
See Also:
Log.info(Object)/**
     * Logs a message with <code>org.apache.log.Priority.INFO</code>.
     *
     * @param message to log
     * @see org.apache.commons.logging.Log#info(Object)
     */
    public void info(Object message) {
        if (message != null) {
            getLogger().info(String.valueOf(message));
        }
    }

    
Logs a message with org.apache.log.Priority.INFO.
Params:
message – to log
t – log this cause
See Also:
Log.info(Object, Throwable)/**
     * Logs a message with <code>org.apache.log.Priority.INFO</code>.
     *
     * @param message to log
     * @param t log this cause
     * @see org.apache.commons.logging.Log#info(Object, Throwable)
     */
    public void info(Object message, Throwable t) {
        if (message != null) {
            getLogger().info(String.valueOf(message), t);
        }
    }

    
Logs a message with org.apache.log.Priority.WARN.
Params:
message – to log
See Also:
Log.warn(Object)/**
     * Logs a message with <code>org.apache.log.Priority.WARN</code>.
     *
     * @param message to log
     * @see org.apache.commons.logging.Log#warn(Object)
     */
    public void warn(Object message) {
        if (message != null) {
            getLogger().warn(String.valueOf(message));
        }
    }

    
Logs a message with org.apache.log.Priority.WARN.
Params:
message – to log
t – log this cause
See Also:
Log.warn(Object, Throwable)/**
     * Logs a message with <code>org.apache.log.Priority.WARN</code>.
     *
     * @param message to log
     * @param t log this cause
     * @see org.apache.commons.logging.Log#warn(Object, Throwable)
     */
    public void warn(Object message, Throwable t) {
        if (message != null) {
            getLogger().warn(String.valueOf(message), t);
        }
    }

    
Logs a message with org.apache.log.Priority.ERROR.
Params:
message – to log
See Also:
Log.error(Object)/**
     * Logs a message with <code>org.apache.log.Priority.ERROR</code>.
     *
     * @param message to log
     * @see org.apache.commons.logging.Log#error(Object)
     */
    public void error(Object message) {
        if (message != null) {
            getLogger().error(String.valueOf(message));
        }
    }

    
Logs a message with org.apache.log.Priority.ERROR.
Params:
message – to log
t – log this cause
See Also:
Log.error(Object, Throwable)/**
     * Logs a message with <code>org.apache.log.Priority.ERROR</code>.
     *
     * @param message to log
     * @param t log this cause
     * @see org.apache.commons.logging.Log#error(Object, Throwable)
     */
    public void error(Object message, Throwable t) {
        if (message != null) {
            getLogger().error(String.valueOf(message), t);
        }
    }

    
Logs a message with org.apache.log.Priority.FATAL_ERROR.
Params:
message – to log
See Also:
Log.fatal(Object)/**
     * Logs a message with <code>org.apache.log.Priority.FATAL_ERROR</code>.
     *
     * @param message to log
     * @see org.apache.commons.logging.Log#fatal(Object)
     */
    public void fatal(Object message) {
        if (message != null) {
            getLogger().fatalError(String.valueOf(message));
        }
    }

    
Logs a message with org.apache.log.Priority.FATAL_ERROR.
Params:
message – to log
t – log this cause
See Also:
Log.fatal(Object, Throwable)/**
     * Logs a message with <code>org.apache.log.Priority.FATAL_ERROR</code>.
     *
     * @param message to log
     * @param t log this cause
     * @see org.apache.commons.logging.Log#fatal(Object, Throwable)
     */
    public void fatal(Object message, Throwable t) {
        if (message != null) {
            getLogger().fatalError(String.valueOf(message), t);
        }
    }

    
Checks whether the LogKit logger will log messages of priority DEBUG.
/**
     * Checks whether the <code>LogKit</code> logger will log messages of priority <code>DEBUG</code>.
     */
    public boolean isDebugEnabled() {
        return getLogger().isDebugEnabled();
    }

    
Checks whether the LogKit logger will log messages of priority ERROR.
/**
     * Checks whether the <code>LogKit</code> logger will log messages of priority <code>ERROR</code>.
     */
    public boolean isErrorEnabled() {
        return getLogger().isErrorEnabled();
    }

    
Checks whether the LogKit logger will log messages of priority FATAL_ERROR.
/**
     * Checks whether the <code>LogKit</code> logger will log messages of priority <code>FATAL_ERROR</code>.
     */
    public boolean isFatalEnabled() {
        return getLogger().isFatalErrorEnabled();
    }

    
Checks whether the LogKit logger will log messages of priority INFO.
/**
     * Checks whether the <code>LogKit</code> logger will log messages of priority <code>INFO</code>.
     */
    public boolean isInfoEnabled() {
        return getLogger().isInfoEnabled();
    }

    
Checks whether the LogKit logger will log messages of priority DEBUG.
/**
     * Checks whether the <code>LogKit</code> logger will log messages of priority <code>DEBUG</code>.
     */
    public boolean isTraceEnabled() {
        return getLogger().isDebugEnabled();
    }

    
Checks whether the LogKit logger will log messages of priority WARN.
/**
     * Checks whether the <code>LogKit</code> logger will log messages of priority <code>WARN</code>.
     */
    public boolean isWarnEnabled() {
        return getLogger().isWarnEnabled();
    }
}