Copyright (c) 2004-2011 QOS.ch
All rights reserved.
Permission is hereby granted, free  of charge, to any person obtaining
a  copy  of this  software  and  associated  documentation files  (the
"Software"), to  deal in  the Software without  restriction, including
without limitation  the rights to  use, copy, modify,  merge, publish,
distribute,  sublicense, and/or sell  copies of  the Software,  and to
permit persons to whom the Software  is furnished to do so, subject to
the following conditions:
The  above  copyright  notice  and  this permission  notice  shall  be
included in all copies or substantial portions of the Software.
THE  SOFTWARE IS  PROVIDED  "AS  IS", WITHOUT  WARRANTY  OF ANY  KIND,
EXPRESS OR  IMPLIED, INCLUDING  BUT NOT LIMITED  TO THE  WARRANTIES OF
MERCHANTABILITY,    FITNESS    FOR    A   PARTICULAR    PURPOSE    AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
OF CONTRACT, TORT OR OTHERWISE,  ARISING FROM, OUT OF OR IN CONNECTION
WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
/**
 * Copyright (c) 2004-2011 QOS.ch
 * All rights reserved.
 *
 * Permission is hereby granted, free  of charge, to any person obtaining
 * a  copy  of this  software  and  associated  documentation files  (the
 * "Software"), to  deal in  the Software without  restriction, including
 * without limitation  the rights to  use, copy, modify,  merge, publish,
 * distribute,  sublicense, and/or sell  copies of  the Software,  and to
 * permit persons to whom the Software  is furnished to do so, subject to
 * the following conditions:
 *
 * The  above  copyright  notice  and  this permission  notice  shall  be
 * included in all copies or substantial portions of the Software.
 *
 * THE  SOFTWARE IS  PROVIDED  "AS  IS", WITHOUT  WARRANTY  OF ANY  KIND,
 * EXPRESS OR  IMPLIED, INCLUDING  BUT NOT LIMITED  TO THE  WARRANTIES OF
 * MERCHANTABILITY,    FITNESS    FOR    A   PARTICULAR    PURPOSE    AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 * OF CONTRACT, TORT OR OTHERWISE,  ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 */
package org.slf4j.helpers;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.Queue;

import org.slf4j.Logger;
import org.slf4j.Marker;
import org.slf4j.event.EventRecodingLogger;
import org.slf4j.event.LoggingEvent;
import org.slf4j.event.SubstituteLoggingEvent;

A logger implementation which logs via a delegate logger. By default, the delegate is a NOPLogger. However, a different delegate can be set at any time. 

See also the relevant
error code documentation.
Author:
Chetan Mehrotra, Ceki Gulcu/**
 * A logger implementation which logs via a delegate logger. By default, the delegate is a
 * {@link NOPLogger}. However, a different delegate can be set at any time.
 * <p/>
 * See also the <a href="http://www.slf4j.org/codes.html#substituteLogger">relevant
 * error code</a> documentation.
 *
 * @author Chetan Mehrotra
 * @author Ceki Gulcu
 */
public class SubstituteLogger implements Logger {

    private final String name;
    private volatile Logger _delegate;
    private Boolean delegateEventAware;
    private Method logMethodCache;
    private EventRecodingLogger eventRecodingLogger;
    private Queue<SubstituteLoggingEvent> eventQueue;

    private final boolean createdPostInitialization;
    
    public SubstituteLogger(String name, Queue<SubstituteLoggingEvent> eventQueue, boolean createdPostInitialization) {
        this.name = name;
        this.eventQueue = eventQueue;
        this.createdPostInitialization = createdPostInitialization;
    }

    public String getName() {
        return name;
    }

    public boolean isTraceEnabled() {
        return delegate().isTraceEnabled();
    }

    public void trace(String msg) {
        delegate().trace(msg);
    }

    public void trace(String format, Object arg) {
        delegate().trace(format, arg);
    }

    public void trace(String format, Object arg1, Object arg2) {
        delegate().trace(format, arg1, arg2);
    }

    public void trace(String format, Object... arguments) {
        delegate().trace(format, arguments);
    }

    public void trace(String msg, Throwable t) {
        delegate().trace(msg, t);
    }

    public boolean isTraceEnabled(Marker marker) {
        return delegate().isTraceEnabled(marker);
    }

    public void trace(Marker marker, String msg) {
        delegate().trace(marker, msg);
    }

    public void trace(Marker marker, String format, Object arg) {
        delegate().trace(marker, format, arg);
    }

    public void trace(Marker marker, String format, Object arg1, Object arg2) {
        delegate().trace(marker, format, arg1, arg2);
    }

    public void trace(Marker marker, String format, Object... arguments) {
        delegate().trace(marker, format, arguments);
    }

    public void trace(Marker marker, String msg, Throwable t) {
        delegate().trace(marker, msg, t);
    }

    public boolean isDebugEnabled() {
        return delegate().isDebugEnabled();
    }

    public void debug(String msg) {
        delegate().debug(msg);
    }

    public void debug(String format, Object arg) {
        delegate().debug(format, arg);
    }

    public void debug(String format, Object arg1, Object arg2) {
        delegate().debug(format, arg1, arg2);
    }

    public void debug(String format, Object... arguments) {
        delegate().debug(format, arguments);
    }

    public void debug(String msg, Throwable t) {
        delegate().debug(msg, t);
    }

    public boolean isDebugEnabled(Marker marker) {
        return delegate().isDebugEnabled(marker);
    }

    public void debug(Marker marker, String msg) {
        delegate().debug(marker, msg);
    }

    public void debug(Marker marker, String format, Object arg) {
        delegate().debug(marker, format, arg);
    }

    public void debug(Marker marker, String format, Object arg1, Object arg2) {
        delegate().debug(marker, format, arg1, arg2);
    }

    public void debug(Marker marker, String format, Object... arguments) {
        delegate().debug(marker, format, arguments);
    }

    public void debug(Marker marker, String msg, Throwable t) {
        delegate().debug(marker, msg, t);
    }

    public boolean isInfoEnabled() {
        return delegate().isInfoEnabled();
    }

    public void info(String msg) {
        delegate().info(msg);
    }

    public void info(String format, Object arg) {
        delegate().info(format, arg);
    }

    public void info(String format, Object arg1, Object arg2) {
        delegate().info(format, arg1, arg2);
    }

    public void info(String format, Object... arguments) {
        delegate().info(format, arguments);
    }

    public void info(String msg, Throwable t) {
        delegate().info(msg, t);
    }

    public boolean isInfoEnabled(Marker marker) {
        return delegate().isInfoEnabled(marker);
    }

    public void info(Marker marker, String msg) {
        delegate().info(marker, msg);
    }

    public void info(Marker marker, String format, Object arg) {
        delegate().info(marker, format, arg);
    }

    public void info(Marker marker, String format, Object arg1, Object arg2) {
        delegate().info(marker, format, arg1, arg2);
    }

    public void info(Marker marker, String format, Object... arguments) {
        delegate().info(marker, format, arguments);
    }

    public void info(Marker marker, String msg, Throwable t) {
        delegate().info(marker, msg, t);
    }

    public boolean isWarnEnabled() {
        return delegate().isWarnEnabled();
    }

    public void warn(String msg) {
        delegate().warn(msg);
    }

    public void warn(String format, Object arg) {
        delegate().warn(format, arg);
    }

    public void warn(String format, Object arg1, Object arg2) {
        delegate().warn(format, arg1, arg2);
    }

    public void warn(String format, Object... arguments) {
        delegate().warn(format, arguments);
    }

    public void warn(String msg, Throwable t) {
        delegate().warn(msg, t);
    }

    public boolean isWarnEnabled(Marker marker) {
        return delegate().isWarnEnabled(marker);
    }

    public void warn(Marker marker, String msg) {
        delegate().warn(marker, msg);
    }

    public void warn(Marker marker, String format, Object arg) {
        delegate().warn(marker, format, arg);
    }

    public void warn(Marker marker, String format, Object arg1, Object arg2) {
        delegate().warn(marker, format, arg1, arg2);
    }

    public void warn(Marker marker, String format, Object... arguments) {
        delegate().warn(marker, format, arguments);
    }

    public void warn(Marker marker, String msg, Throwable t) {
        delegate().warn(marker, msg, t);
    }

    public boolean isErrorEnabled() {
        return delegate().isErrorEnabled();
    }

    public void error(String msg) {
        delegate().error(msg);
    }

    public void error(String format, Object arg) {
        delegate().error(format, arg);
    }

    public void error(String format, Object arg1, Object arg2) {
        delegate().error(format, arg1, arg2);
    }

    public void error(String format, Object... arguments) {
        delegate().error(format, arguments);
    }

    public void error(String msg, Throwable t) {
        delegate().error(msg, t);
    }

    public boolean isErrorEnabled(Marker marker) {
        return delegate().isErrorEnabled(marker);
    }

    public void error(Marker marker, String msg) {
        delegate().error(marker, msg);
    }

    public void error(Marker marker, String format, Object arg) {
        delegate().error(marker, format, arg);
    }

    public void error(Marker marker, String format, Object arg1, Object arg2) {
        delegate().error(marker, format, arg1, arg2);
    }

    public void error(Marker marker, String format, Object... arguments) {
        delegate().error(marker, format, arguments);
    }

    public void error(Marker marker, String msg, Throwable t) {
        delegate().error(marker, msg, t);
    }

    @Override
    public boolean equals(Object o) {
        if (this == o)
            return true;
        if (o == null || getClass() != o.getClass())
            return false;

        SubstituteLogger that = (SubstituteLogger) o;

        if (!name.equals(that.name))
            return false;

        return true;
    }

    @Override
    public int hashCode() {
        return name.hashCode();
    }

    
Return the delegate logger instance if set. Otherwise, return a NOPLogger instance. /**
     * Return the delegate logger instance if set. Otherwise, return a {@link NOPLogger}
     * instance.
     */
    Logger delegate() {
        if(_delegate != null) {
            return _delegate;
        }
        if(createdPostInitialization) {
            return NOPLogger.NOP_LOGGER;
        } else {
            return getEventRecordingLogger();
        }
    }

    private Logger getEventRecordingLogger() {
        if (eventRecodingLogger == null) {
            eventRecodingLogger = new EventRecodingLogger(this, eventQueue);
        }
        return eventRecodingLogger;
    }

    
Typically called after the LoggerFactory initialization phase is completed. 
Params:
delegate – /**
     * Typically called after the {@link org.slf4j.LoggerFactory} initialization phase is completed.
     * @param delegate
     */
    public void setDelegate(Logger delegate) {
        this._delegate = delegate;
    }

    public boolean isDelegateEventAware() {
        if (delegateEventAware != null)
            return delegateEventAware;

        try {
            logMethodCache = _delegate.getClass().getMethod("log", LoggingEvent.class);
            delegateEventAware = Boolean.TRUE;
        } catch (NoSuchMethodException e) {
            delegateEventAware = Boolean.FALSE;
        }
        return delegateEventAware;
    }

    public void log(LoggingEvent event) {
        if (isDelegateEventAware()) {
            try {
                logMethodCache.invoke(_delegate, event);
            } catch (IllegalAccessException e) {
            } catch (IllegalArgumentException e) {
            } catch (InvocationTargetException e) {
            }
        }
    }


    public boolean isDelegateNull() {
        return _delegate == null;
    }

    public boolean isDelegateNOP() {
        return _delegate instanceof NOPLogger;
    }
}