/*
 * Copyright 2012 The Netty Project
 *
 * The Netty Project 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.
 */
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 io.netty.util.internal.logging;

Internal-use-only logger used by Netty.  DO NOT
access this class outside of Netty.
/**
 * <em>Internal-use-only</em> logger used by Netty.  <strong>DO NOT</strong>
 * access this class outside of Netty.
 */
public interface InternalLogger {

    
Return the name of this InternalLogger instance. 
Returns:
name of this logger instance/**
     * Return the name of this {@link InternalLogger} instance.
     *
     * @return name of this logger instance
     */
    String name();

    
Is the logger instance enabled for the TRACE level?
Returns:
True if this Logger is enabled for the TRACE level,
        false otherwise./**
     * Is the logger instance enabled for the TRACE level?
     *
     * @return True if this Logger is enabled for the TRACE level,
     *         false otherwise.
     */
    boolean isTraceEnabled();

    
Log a message at the TRACE level.
Params:
msg – the message string to be logged/**
     * Log a message at the TRACE level.
     *
     * @param msg the message string to be logged
     */
    void trace(String msg);

    
Log a message at the TRACE level according to the specified format
and argument.

This form avoids superfluous object creation when the logger
is disabled for the TRACE level. 
Params:
format – the format string
arg –    the argument/**
     * Log a message at the TRACE level according to the specified format
     * and argument.
     * <p/>
     * <p>This form avoids superfluous object creation when the logger
     * is disabled for the TRACE level. </p>
     *
     * @param format the format string
     * @param arg    the argument
     */
    void trace(String format, Object arg);

    
Log a message at the TRACE level according to the specified format
and arguments.

This form avoids superfluous object creation when the logger
is disabled for the TRACE level. 
Params:
format – the format string
argA –   the first argument
argB –   the second argument/**
     * Log a message at the TRACE level according to the specified format
     * and arguments.
     * <p/>
     * <p>This form avoids superfluous object creation when the logger
     * is disabled for the TRACE level. </p>
     *
     * @param format the format string
     * @param argA   the first argument
     * @param argB   the second argument
     */
    void trace(String format, Object argA, Object argB);

    
Log a message at the TRACE level according to the specified format
and arguments.

This form avoids superfluous string concatenation when the logger is disabled for the TRACE level. However, this variant incurs the hidden (and relatively small) cost of creating an Object[] before invoking the method, even if this logger is disabled for TRACE. The variants taking one and two arguments exist solely in order to avoid this hidden cost.
Params:
format –    the format string
arguments – a list of 3 or more arguments/**
     * Log a message at the TRACE level according to the specified format
     * and arguments.
     * <p/>
     * <p>This form avoids superfluous string concatenation when the logger
     * is disabled for the TRACE level. However, this variant incurs the hidden
     * (and relatively small) cost of creating an {@code Object[]} before invoking the method,
     * even if this logger is disabled for TRACE. The variants taking {@link #trace(String, Object) one} and
     * {@link #trace(String, Object, Object) two} arguments exist solely in order to avoid this hidden cost.</p>
     *
     * @param format    the format string
     * @param arguments a list of 3 or more arguments
     */
    void trace(String format, Object... arguments);

    
Log an exception (throwable) at the TRACE level with an
accompanying message.
Params:
msg – the message accompanying the exception
t –   the exception (throwable) to log/**
     * Log an exception (throwable) at the TRACE level with an
     * accompanying message.
     *
     * @param msg the message accompanying the exception
     * @param t   the exception (throwable) to log
     */
    void trace(String msg, Throwable t);

    
Log an exception (throwable) at the TRACE level.
Params:
t –   the exception (throwable) to log/**
     * Log an exception (throwable) at the TRACE level.
     *
     * @param t   the exception (throwable) to log
     */
    void trace(Throwable t);

    
Is the logger instance enabled for the DEBUG level?
Returns:
True if this Logger is enabled for the DEBUG level,
        false otherwise./**
     * Is the logger instance enabled for the DEBUG level?
     *
     * @return True if this Logger is enabled for the DEBUG level,
     *         false otherwise.
     */
    boolean isDebugEnabled();

    
Log a message at the DEBUG level.
Params:
msg – the message string to be logged/**
     * Log a message at the DEBUG level.
     *
     * @param msg the message string to be logged
     */
    void debug(String msg);

    
Log a message at the DEBUG level according to the specified format
and argument.

This form avoids superfluous object creation when the logger
is disabled for the DEBUG level. 
Params:
format – the format string
arg –    the argument/**
     * Log a message at the DEBUG level according to the specified format
     * and argument.
     * <p/>
     * <p>This form avoids superfluous object creation when the logger
     * is disabled for the DEBUG level. </p>
     *
     * @param format the format string
     * @param arg    the argument
     */
    void debug(String format, Object arg);

    
Log a message at the DEBUG level according to the specified format
and arguments.

This form avoids superfluous object creation when the logger
is disabled for the DEBUG level. 
Params:
format – the format string
argA –   the first argument
argB –   the second argument/**
     * Log a message at the DEBUG level according to the specified format
     * and arguments.
     * <p/>
     * <p>This form avoids superfluous object creation when the logger
     * is disabled for the DEBUG level. </p>
     *
     * @param format the format string
     * @param argA   the first argument
     * @param argB   the second argument
     */
    void debug(String format, Object argA, Object argB);

    
Log a message at the DEBUG level according to the specified format
and arguments.

This form avoids superfluous string concatenation when the logger is disabled for the DEBUG level. However, this variant incurs the hidden (and relatively small) cost of creating an Object[] before invoking the method, even if this logger is disabled for DEBUG. The variants taking one and two arguments exist solely in order to avoid this hidden cost.
Params:
format –    the format string
arguments – a list of 3 or more arguments/**
     * Log a message at the DEBUG level according to the specified format
     * and arguments.
     * <p/>
     * <p>This form avoids superfluous string concatenation when the logger
     * is disabled for the DEBUG level. However, this variant incurs the hidden
     * (and relatively small) cost of creating an {@code Object[]} before invoking the method,
     * even if this logger is disabled for DEBUG. The variants taking
     * {@link #debug(String, Object) one} and {@link #debug(String, Object, Object) two}
     * arguments exist solely in order to avoid this hidden cost.</p>
     *
     * @param format    the format string
     * @param arguments a list of 3 or more arguments
     */
    void debug(String format, Object... arguments);

    
Log an exception (throwable) at the DEBUG level with an
accompanying message.
Params:
msg – the message accompanying the exception
t –   the exception (throwable) to log/**
     * Log an exception (throwable) at the DEBUG level with an
     * accompanying message.
     *
     * @param msg the message accompanying the exception
     * @param t   the exception (throwable) to log
     */
    void debug(String msg, Throwable t);

    
Log an exception (throwable) at the DEBUG level.
Params:
t –   the exception (throwable) to log/**
     * Log an exception (throwable) at the DEBUG level.
     *
     * @param t   the exception (throwable) to log
     */
    void debug(Throwable t);

    
Is the logger instance enabled for the INFO level?
Returns:
True if this Logger is enabled for the INFO level,
        false otherwise./**
     * Is the logger instance enabled for the INFO level?
     *
     * @return True if this Logger is enabled for the INFO level,
     *         false otherwise.
     */
    boolean isInfoEnabled();

    
Log a message at the INFO level.
Params:
msg – the message string to be logged/**
     * Log a message at the INFO level.
     *
     * @param msg the message string to be logged
     */
    void info(String msg);

    
Log a message at the INFO level according to the specified format
and argument.

This form avoids superfluous object creation when the logger
is disabled for the INFO level. 
Params:
format – the format string
arg –    the argument/**
     * Log a message at the INFO level according to the specified format
     * and argument.
     * <p/>
     * <p>This form avoids superfluous object creation when the logger
     * is disabled for the INFO level. </p>
     *
     * @param format the format string
     * @param arg    the argument
     */
    void info(String format, Object arg);

    
Log a message at the INFO level according to the specified format
and arguments.

This form avoids superfluous object creation when the logger
is disabled for the INFO level. 
Params:
format – the format string
argA –   the first argument
argB –   the second argument/**
     * Log a message at the INFO level according to the specified format
     * and arguments.
     * <p/>
     * <p>This form avoids superfluous object creation when the logger
     * is disabled for the INFO level. </p>
     *
     * @param format the format string
     * @param argA   the first argument
     * @param argB   the second argument
     */
    void info(String format, Object argA, Object argB);

    
Log a message at the INFO level according to the specified format
and arguments.

This form avoids superfluous string concatenation when the logger is disabled for the INFO level. However, this variant incurs the hidden (and relatively small) cost of creating an Object[] before invoking the method, even if this logger is disabled for INFO. The variants taking one and two arguments exist solely in order to avoid this hidden cost.
Params:
format –    the format string
arguments – a list of 3 or more arguments/**
     * Log a message at the INFO level according to the specified format
     * and arguments.
     * <p/>
     * <p>This form avoids superfluous string concatenation when the logger
     * is disabled for the INFO level. However, this variant incurs the hidden
     * (and relatively small) cost of creating an {@code Object[]} before invoking the method,
     * even if this logger is disabled for INFO. The variants taking
     * {@link #info(String, Object) one} and {@link #info(String, Object, Object) two}
     * arguments exist solely in order to avoid this hidden cost.</p>
     *
     * @param format    the format string
     * @param arguments a list of 3 or more arguments
     */
    void info(String format, Object... arguments);

    
Log an exception (throwable) at the INFO level with an
accompanying message.
Params:
msg – the message accompanying the exception
t –   the exception (throwable) to log/**
     * Log an exception (throwable) at the INFO level with an
     * accompanying message.
     *
     * @param msg the message accompanying the exception
     * @param t   the exception (throwable) to log
     */
    void info(String msg, Throwable t);

    
Log an exception (throwable) at the INFO level.
Params:
t –   the exception (throwable) to log/**
     * Log an exception (throwable) at the INFO level.
     *
     * @param t   the exception (throwable) to log
     */
    void info(Throwable t);

    
Is the logger instance enabled for the WARN level?
Returns:
True if this Logger is enabled for the WARN level,
        false otherwise./**
     * Is the logger instance enabled for the WARN level?
     *
     * @return True if this Logger is enabled for the WARN level,
     *         false otherwise.
     */
    boolean isWarnEnabled();

    
Log a message at the WARN level.
Params:
msg – the message string to be logged/**
     * Log a message at the WARN level.
     *
     * @param msg the message string to be logged
     */
    void warn(String msg);

    
Log a message at the WARN level according to the specified format
and argument.

This form avoids superfluous object creation when the logger
is disabled for the WARN level. 
Params:
format – the format string
arg –    the argument/**
     * Log a message at the WARN level according to the specified format
     * and argument.
     * <p/>
     * <p>This form avoids superfluous object creation when the logger
     * is disabled for the WARN level. </p>
     *
     * @param format the format string
     * @param arg    the argument
     */
    void warn(String format, Object arg);

    
Log a message at the WARN level according to the specified format
and arguments.

This form avoids superfluous string concatenation when the logger is disabled for the WARN level. However, this variant incurs the hidden (and relatively small) cost of creating an Object[] before invoking the method, even if this logger is disabled for WARN. The variants taking one and two arguments exist solely in order to avoid this hidden cost.
Params:
format –    the format string
arguments – a list of 3 or more arguments/**
     * Log a message at the WARN level according to the specified format
     * and arguments.
     * <p/>
     * <p>This form avoids superfluous string concatenation when the logger
     * is disabled for the WARN level. However, this variant incurs the hidden
     * (and relatively small) cost of creating an {@code Object[]} before invoking the method,
     * even if this logger is disabled for WARN. The variants taking
     * {@link #warn(String, Object) one} and {@link #warn(String, Object, Object) two}
     * arguments exist solely in order to avoid this hidden cost.</p>
     *
     * @param format    the format string
     * @param arguments a list of 3 or more arguments
     */
    void warn(String format, Object... arguments);

    
Log a message at the WARN level according to the specified format
and arguments.

This form avoids superfluous object creation when the logger
is disabled for the WARN level. 
Params:
format – the format string
argA –   the first argument
argB –   the second argument/**
     * Log a message at the WARN level according to the specified format
     * and arguments.
     * <p/>
     * <p>This form avoids superfluous object creation when the logger
     * is disabled for the WARN level. </p>
     *
     * @param format the format string
     * @param argA   the first argument
     * @param argB   the second argument
     */
    void warn(String format, Object argA, Object argB);

    
Log an exception (throwable) at the WARN level with an
accompanying message.
Params:
msg – the message accompanying the exception
t –   the exception (throwable) to log/**
     * Log an exception (throwable) at the WARN level with an
     * accompanying message.
     *
     * @param msg the message accompanying the exception
     * @param t   the exception (throwable) to log
     */
    void warn(String msg, Throwable t);

    
Log an exception (throwable) at the WARN level.
Params:
t –   the exception (throwable) to log/**
     * Log an exception (throwable) at the WARN level.
     *
     * @param t   the exception (throwable) to log
     */
    void warn(Throwable t);

    
Is the logger instance enabled for the ERROR level?
Returns:
True if this Logger is enabled for the ERROR level,
        false otherwise./**
     * Is the logger instance enabled for the ERROR level?
     *
     * @return True if this Logger is enabled for the ERROR level,
     *         false otherwise.
     */
    boolean isErrorEnabled();

    
Log a message at the ERROR level.
Params:
msg – the message string to be logged/**
     * Log a message at the ERROR level.
     *
     * @param msg the message string to be logged
     */
    void error(String msg);

    
Log a message at the ERROR level according to the specified format
and argument.

This form avoids superfluous object creation when the logger
is disabled for the ERROR level. 
Params:
format – the format string
arg –    the argument/**
     * Log a message at the ERROR level according to the specified format
     * and argument.
     * <p/>
     * <p>This form avoids superfluous object creation when the logger
     * is disabled for the ERROR level. </p>
     *
     * @param format the format string
     * @param arg    the argument
     */
    void error(String format, Object arg);

    
Log a message at the ERROR level according to the specified format
and arguments.

This form avoids superfluous object creation when the logger
is disabled for the ERROR level. 
Params:
format – the format string
argA –   the first argument
argB –   the second argument/**
     * Log a message at the ERROR level according to the specified format
     * and arguments.
     * <p/>
     * <p>This form avoids superfluous object creation when the logger
     * is disabled for the ERROR level. </p>
     *
     * @param format the format string
     * @param argA   the first argument
     * @param argB   the second argument
     */
    void error(String format, Object argA, Object argB);

    
Log a message at the ERROR level according to the specified format
and arguments.

This form avoids superfluous string concatenation when the logger is disabled for the ERROR level. However, this variant incurs the hidden (and relatively small) cost of creating an Object[] before invoking the method, even if this logger is disabled for ERROR. The variants taking one and two arguments exist solely in order to avoid this hidden cost.
Params:
format –    the format string
arguments – a list of 3 or more arguments/**
     * Log a message at the ERROR level according to the specified format
     * and arguments.
     * <p/>
     * <p>This form avoids superfluous string concatenation when the logger
     * is disabled for the ERROR level. However, this variant incurs the hidden
     * (and relatively small) cost of creating an {@code Object[]} before invoking the method,
     * even if this logger is disabled for ERROR. The variants taking
     * {@link #error(String, Object) one} and {@link #error(String, Object, Object) two}
     * arguments exist solely in order to avoid this hidden cost.</p>
     *
     * @param format    the format string
     * @param arguments a list of 3 or more arguments
     */
    void error(String format, Object... arguments);

    
Log an exception (throwable) at the ERROR level with an
accompanying message.
Params:
msg – the message accompanying the exception
t –   the exception (throwable) to log/**
     * Log an exception (throwable) at the ERROR level with an
     * accompanying message.
     *
     * @param msg the message accompanying the exception
     * @param t   the exception (throwable) to log
     */
    void error(String msg, Throwable t);

    
Log an exception (throwable) at the ERROR level.
Params:
t –   the exception (throwable) to log/**
     * Log an exception (throwable) at the ERROR level.
     *
     * @param t   the exception (throwable) to log
     */
    void error(Throwable t);

    
Is the logger instance enabled for the specified level? 
Returns:
True if this Logger is enabled for the specified level, false otherwise./**
     * Is the logger instance enabled for the specified {@code level}?
     *
     * @return True if this Logger is enabled for the specified {@code level},
     *         false otherwise.
     */
    boolean isEnabled(InternalLogLevel level);

    
Log a message at the specified level. 
Params:
msg – the message string to be logged/**
     * Log a message at the specified {@code level}.
     *
     * @param msg the message string to be logged
     */
    void log(InternalLogLevel level, String msg);

    
Log a message at the specified level according to the specified format and argument. 

This form avoids superfluous object creation when the logger is disabled for the specified level. 
Params:
format – the format string
arg –    the argument/**
     * Log a message at the specified {@code level} according to the specified format
     * and argument.
     * <p/>
     * <p>This form avoids superfluous object creation when the logger
     * is disabled for the specified {@code level}. </p>
     *
     * @param format the format string
     * @param arg    the argument
     */
    void log(InternalLogLevel level, String format, Object arg);

    
Log a message at the specified level according to the specified format and arguments. 

This form avoids superfluous object creation when the logger is disabled for the specified level. 
Params:
format – the format string
argA –   the first argument
argB –   the second argument/**
     * Log a message at the specified {@code level} according to the specified format
     * and arguments.
     * <p/>
     * <p>This form avoids superfluous object creation when the logger
     * is disabled for the specified {@code level}. </p>
     *
     * @param format the format string
     * @param argA   the first argument
     * @param argB   the second argument
     */
    void log(InternalLogLevel level, String format, Object argA, Object argB);

    
Log a message at the specified level according to the specified format and arguments. 

This form avoids superfluous string concatenation when the logger is disabled for the specified level. However, this variant incurs the hidden (and relatively small) cost of creating an Object[] before invoking the method, even if this logger is disabled for the specified level. The variants taking one and two arguments exist solely in order to avoid this hidden cost.
Params:
format –    the format string
arguments – a list of 3 or more arguments/**
     * Log a message at the specified {@code level} according to the specified format
     * and arguments.
     * <p/>
     * <p>This form avoids superfluous string concatenation when the logger
     * is disabled for the specified {@code level}. However, this variant incurs the hidden
     * (and relatively small) cost of creating an {@code Object[]} before invoking the method,
     * even if this logger is disabled for the specified {@code level}. The variants taking
     * {@link #log(InternalLogLevel, String, Object) one} and
     * {@link #log(InternalLogLevel, String, Object, Object) two} arguments exist solely
     * in order to avoid this hidden cost.</p>
     *
     * @param format    the format string
     * @param arguments a list of 3 or more arguments
     */
    void log(InternalLogLevel level, String format, Object... arguments);

    
Log an exception (throwable) at the specified level with an accompanying message. 
Params:
msg – the message accompanying the exception
t –   the exception (throwable) to log/**
     * Log an exception (throwable) at the specified {@code level} with an
     * accompanying message.
     *
     * @param msg the message accompanying the exception
     * @param t   the exception (throwable) to log
     */
    void log(InternalLogLevel level, String msg, Throwable t);

    
Log an exception (throwable) at the specified level. 
Params:
t –   the exception (throwable) to log/**
     * Log an exception (throwable) at the specified {@code level}.
     *
     * @param t   the exception (throwable) to log
     */
    void log(InternalLogLevel level, Throwable t);
}