org.slf4j/slf4j-simple/1.7.26 : org/slf4j/impl/SimpleLogger.java

SimpleLogger
http://www.slf4j.org: SLF4J Simple binding (QOS.ch)
MIT License
Ceki Gulcu
Copyright (c) 2004-2012 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) 2004-2012 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.impl;

import java.io.PrintStream;
import java.util.Date;

import org.slf4j.Logger;
import org.slf4j.event.LoggingEvent;
import org.slf4j.helpers.FormattingTuple;
import org.slf4j.helpers.MarkerIgnoringBase;
import org.slf4j.helpers.MessageFormatter;
import org.slf4j.spi.LocationAwareLogger;

 Simple implementation of Logger that sends all enabled log messages, for all defined loggers, to the console (System.err). The following system properties are supported to configure the behavior of this logger: 

org.slf4j.simpleLogger.logFile - The output target which can
be the path to a file, or the special values "System.out" and
"System.err". Default is "System.err".
org.slf4j.simpleLogger.cacheOutputStream - If the output
target is set to "System.out" or "System.err" (see preceding entry), by
default, logs will be output to the latest value referenced by
System.out/err variables. By setting this
parameter to true, the output stream will be cached, i.e. assigned once at
initialization time and re-used independently of the current value referenced by
 System.out/err.

org.slf4j.simpleLogger.defaultLogLevel - Default log level
for all instances of SimpleLogger. Must be one of ("trace", "debug", "info",
"warn", "error" or "off"). If not specified, defaults to "info".
org.slf4j.simpleLogger.log.a.b.c - Logging detail
level for a SimpleLogger instance named "a.b.c". Right-side value must be one
of "trace", "debug", "info", "warn", "error" or "off". When a SimpleLogger
named "a.b.c" is initialized, its level is assigned from this property. If
unspecified, the level of nearest parent logger will be used, and if none is
set, then the value specified by
org.slf4j.simpleLogger.defaultLogLevel will be used.
org.slf4j.simpleLogger.showDateTime - Set to
true if you want the current date and time to be included in
output messages. Default is false
org.slf4j.simpleLogger.dateTimeFormat - The date and time
format to be used in the output messages. The pattern describing the date and
time format is defined by 
SimpleDateFormat. If the format is not specified or is
invalid, the number of milliseconds since start up will be output.
org.slf4j.simpleLogger.showThreadName -Set to
true if you want to output the current thread name. Defaults to
true.
org.slf4j.simpleLogger.showLogName - Set to
true if you want the Logger instance name to be included in
output messages. Defaults to true.
org.slf4j.simpleLogger.showShortLogName - Set to
true if you want the last component of the name to be included
in output messages. Defaults to false.
org.slf4j.simpleLogger.levelInBrackets - Should the level
string be output in brackets? Defaults to false.
org.slf4j.simpleLogger.warnLevelString - The string value
output for the warn level. Defaults to WARN.


In addition to looking for system properties with the names specified above,
this implementation also checks for a class loader resource named
"simplelogger.properties", and includes any matching definitions
from this resource (if it exists).


With no configuration, the default output includes the relative time in
milliseconds, thread name, the level, logger name, and the message followed
by the line separator for the host. In log4j terms it amounts to the "%r [%t]
%level %logger - %m%n" pattern.


Sample output follows.

176 [main] INFO examples.Sort - Populating an array of 2 elements in reverse order.
225 [main] INFO examples.SortAlgo - Entered the sort method.
304 [main] INFO examples.SortAlgo - Dump of integer array:
317 [main] INFO examples.SortAlgo - Element [0] = 0
331 [main] INFO examples.SortAlgo - Element [1] = 1
343 [main] INFO examples.Sort - The next log statement should be an error message.
346 [main] ERROR examples.SortAlgo - Tried to dump an uninitialized array.
  at org.log4j.examples.SortAlgo.dump(SortAlgo.java:58)
  at org.log4j.examples.Sort.main(Sort.java:64)
467 [main] INFO  examples.Sort - Exiting main method.


This implementation is heavily inspired by
Apache Commons Logging's
SimpleLog.

Author: Ceki Gülcü, Scott Sanders, Rod Waldhoff, Robert Burrell Donkin, Cédrik LIME/**
 * <p>
 * Simple implementation of {@link Logger} that sends all enabled log messages,
 * for all defined loggers, to the console ({@code System.err}). The following
 * system properties are supported to configure the behavior of this logger:
 * </p>
 *
 * <ul>
 * <li><code>org.slf4j.simpleLogger.logFile</code> - The output target which can
 * be the <em>path</em> to a file, or the special values "System.out" and
 * "System.err". Default is "System.err".</li>
 * 
 * <li><code>org.slf4j.simpleLogger.cacheOutputStream</code> - If the output
 * target is set to "System.out" or "System.err" (see preceding entry), by
 * default, logs will be output to the latest value referenced by
 * <code>System.out/err</code> variables. By setting this
 * parameter to true, the output stream will be cached, i.e. assigned once at
 * initialization time and re-used independently of the current value referenced by
 *  <code>System.out/err</code>.
 * </li>
 * 
 * <li><code>org.slf4j.simpleLogger.defaultLogLevel</code> - Default log level
 * for all instances of SimpleLogger. Must be one of ("trace", "debug", "info",
 * "warn", "error" or "off"). If not specified, defaults to "info".</li>
 *
 * <li><code>org.slf4j.simpleLogger.log.<em>a.b.c</em></code> - Logging detail
 * level for a SimpleLogger instance named "a.b.c". Right-side value must be one
 * of "trace", "debug", "info", "warn", "error" or "off". When a SimpleLogger
 * named "a.b.c" is initialized, its level is assigned from this property. If
 * unspecified, the level of nearest parent logger will be used, and if none is
 * set, then the value specified by
 * <code>org.slf4j.simpleLogger.defaultLogLevel</code> will be used.</li>
 *
 * <li><code>org.slf4j.simpleLogger.showDateTime</code> - Set to
 * <code>true</code> if you want the current date and time to be included in
 * output messages. Default is <code>false</code></li>
 *
 * <li><code>org.slf4j.simpleLogger.dateTimeFormat</code> - The date and time
 * format to be used in the output messages. The pattern describing the date and
 * time format is defined by <a href=
 * "http://docs.oracle.com/javase/1.5.0/docs/api/java/text/SimpleDateFormat.html">
 * <code>SimpleDateFormat</code></a>. If the format is not specified or is
 * invalid, the number of milliseconds since start up will be output.</li>
 *
 * <li><code>org.slf4j.simpleLogger.showThreadName</code> -Set to
 * <code>true</code> if you want to output the current thread name. Defaults to
 * <code>true</code>.</li>
 *
 * <li><code>org.slf4j.simpleLogger.showLogName</code> - Set to
 * <code>true</code> if you want the Logger instance name to be included in
 * output messages. Defaults to <code>true</code>.</li>
 *
 * <li><code>org.slf4j.simpleLogger.showShortLogName</code> - Set to
 * <code>true</code> if you want the last component of the name to be included
 * in output messages. Defaults to <code>false</code>.</li>
 *
 * <li><code>org.slf4j.simpleLogger.levelInBrackets</code> - Should the level
 * string be output in brackets? Defaults to <code>false</code>.</li>
 *
 * <li><code>org.slf4j.simpleLogger.warnLevelString</code> - The string value
 * output for the warn level. Defaults to <code>WARN</code>.</li>
 * 
 * </ul>
 *
 * <p>
 * In addition to looking for system properties with the names specified above,
 * this implementation also checks for a class loader resource named
 * <code>"simplelogger.properties"</code>, and includes any matching definitions
 * from this resource (if it exists).
 * </p>
 *
 * <p>
 * With no configuration, the default output includes the relative time in
 * milliseconds, thread name, the level, logger name, and the message followed
 * by the line separator for the host. In log4j terms it amounts to the "%r [%t]
 * %level %logger - %m%n" pattern.
 * </p>
 * <p>
 * Sample output follows.
 * </p>
 * 
 * <pre>
 * 176 [main] INFO examples.Sort - Populating an array of 2 elements in reverse order.
 * 225 [main] INFO examples.SortAlgo - Entered the sort method.
 * 304 [main] INFO examples.SortAlgo - Dump of integer array:
 * 317 [main] INFO examples.SortAlgo - Element [0] = 0
 * 331 [main] INFO examples.SortAlgo - Element [1] = 1
 * 343 [main] INFO examples.Sort - The next log statement should be an error message.
 * 346 [main] ERROR examples.SortAlgo - Tried to dump an uninitialized array.
 *   at org.log4j.examples.SortAlgo.dump(SortAlgo.java:58)
 *   at org.log4j.examples.Sort.main(Sort.java:64)
 * 467 [main] INFO  examples.Sort - Exiting main method.
 * </pre>
 *
 * <p>
 * This implementation is heavily inspired by
 * <a href="http://commons.apache.org/logging/">Apache Commons Logging</a>'s
 * SimpleLog.
 * </p>
 *
 * @author Ceki G&uuml;lc&uuml;
 * @author Scott Sanders
 * @author Rod Waldhoff
 * @author Robert Burrell Donkin
 * @author C&eacute;drik LIME
 */
public class SimpleLogger extends MarkerIgnoringBase {

    private static final long serialVersionUID = -632788891211436180L;

    private static long START_TIME = System.currentTimeMillis();

    protected static final int LOG_LEVEL_TRACE = LocationAwareLogger.TRACE_INT;
    protected static final int LOG_LEVEL_DEBUG = LocationAwareLogger.DEBUG_INT;
    protected static final int LOG_LEVEL_INFO = LocationAwareLogger.INFO_INT;
    protected static final int LOG_LEVEL_WARN = LocationAwareLogger.WARN_INT;
    protected static final int LOG_LEVEL_ERROR = LocationAwareLogger.ERROR_INT;
    // The OFF level can only be used in configuration files to disable logging.
    // It has
    // no printing method associated with it in o.s.Logger interface.
    protected static final int LOG_LEVEL_OFF = LOG_LEVEL_ERROR + 10;

    private static boolean INITIALIZED = false;
    static SimpleLoggerConfiguration CONFIG_PARAMS = null;

    static void lazyInit() {
        if (INITIALIZED) {
            return;
        }
        INITIALIZED = true;
        init();
    }

    // external software might be invoking this method directly. Do not rename
    // or change its semantics.
    static void init() {
        CONFIG_PARAMS = new SimpleLoggerConfiguration();
        CONFIG_PARAMS.init();
    }

    The current log level /** The current log level */
    protected int currentLogLevel = LOG_LEVEL_INFO;
    The short name of this simple log instance /** The short name of this simple log instance */
    private transient String shortLogName = null;

    All system properties used by SimpleLogger start with this
prefix
/**
     * All system properties used by <code>SimpleLogger</code> start with this
     * prefix
     */
    public static final String SYSTEM_PREFIX = "org.slf4j.simpleLogger.";

    public static final String LOG_KEY_PREFIX = SimpleLogger.SYSTEM_PREFIX + "log.";

    public static final String CACHE_OUTPUT_STREAM_STRING_KEY = SimpleLogger.SYSTEM_PREFIX + "cacheOutputStream";

    public static final String WARN_LEVEL_STRING_KEY = SimpleLogger.SYSTEM_PREFIX + "warnLevelString";

    public static final String LEVEL_IN_BRACKETS_KEY = SimpleLogger.SYSTEM_PREFIX + "levelInBrackets";

    public static final String LOG_FILE_KEY = SimpleLogger.SYSTEM_PREFIX + "logFile";

    public static final String SHOW_SHORT_LOG_NAME_KEY = SimpleLogger.SYSTEM_PREFIX + "showShortLogName";

    public static final String SHOW_LOG_NAME_KEY = SimpleLogger.SYSTEM_PREFIX + "showLogName";

    public static final String SHOW_THREAD_NAME_KEY = SimpleLogger.SYSTEM_PREFIX + "showThreadName";

    public static final String DATE_TIME_FORMAT_KEY = SimpleLogger.SYSTEM_PREFIX + "dateTimeFormat";

    public static final String SHOW_DATE_TIME_KEY = SimpleLogger.SYSTEM_PREFIX + "showDateTime";

    public static final String DEFAULT_LOG_LEVEL_KEY = SimpleLogger.SYSTEM_PREFIX + "defaultLogLevel";

    Package access allows only SimpleLoggerFactory to instantiate SimpleLogger instances. /**
     * Package access allows only {@link SimpleLoggerFactory} to instantiate
     * SimpleLogger instances.
     */
    SimpleLogger(String name) {
        this.name = name;

        String levelString = recursivelyComputeLevelString();
        if (levelString != null) {
            this.currentLogLevel = SimpleLoggerConfiguration.stringToLevel(levelString);
        } else {
            this.currentLogLevel = CONFIG_PARAMS.defaultLogLevel;
        }
    }

    String recursivelyComputeLevelString() {
        String tempName = name;
        String levelString = null;
        int indexOfLastDot = tempName.length();
        while ((levelString == null) && (indexOfLastDot > -1)) {
            tempName = tempName.substring(0, indexOfLastDot);
            levelString = CONFIG_PARAMS.getStringProperty(SimpleLogger.LOG_KEY_PREFIX + tempName, null);
            indexOfLastDot = String.valueOf(tempName).lastIndexOf(".");
        }
        return levelString;
    }

    This is our internal implementation for logging regular
(non-parameterized) log messages.
Params: level – 
           One of the LOG_LEVEL_XXX constants defining the log level
message – 
           The message itself
t – 
           The exception whose stack trace should be logged/**
     * This is our internal implementation for logging regular
     * (non-parameterized) log messages.
     *
     * @param level
     *            One of the LOG_LEVEL_XXX constants defining the log level
     * @param message
     *            The message itself
     * @param t
     *            The exception whose stack trace should be logged
     */
    private void log(int level, String message, Throwable t) {
        if (!isLevelEnabled(level)) {
            return;
        }

        StringBuilder buf = new StringBuilder(32);

        // Append date-time if so configured
        if (CONFIG_PARAMS.showDateTime) {
            if (CONFIG_PARAMS.dateFormatter != null) {
                buf.append(getFormattedDate());
                buf.append(' ');
            } else {
                buf.append(System.currentTimeMillis() - START_TIME);
                buf.append(' ');
            }
        }

        // Append current thread name if so configured
        if (CONFIG_PARAMS.showThreadName) {
            buf.append('[');
            buf.append(Thread.currentThread().getName());
            buf.append("] ");
        }

        if (CONFIG_PARAMS.levelInBrackets)
            buf.append('[');

        // Append a readable representation of the log level
        String levelStr = renderLevel(level);
        buf.append(levelStr);
        if (CONFIG_PARAMS.levelInBrackets)
            buf.append(']');
        buf.append(' ');

        // Append the name of the log instance if so configured
        if (CONFIG_PARAMS.showShortLogName) {
            if (shortLogName == null)
                shortLogName = computeShortName();
            buf.append(String.valueOf(shortLogName)).append(" - ");
        } else if (CONFIG_PARAMS.showLogName) {
            buf.append(String.valueOf(name)).append(" - ");
        }

        // Append the message
        buf.append(message);

        write(buf, t);

    }

    protected String renderLevel(int level) {
        switch (level) {
        case LOG_LEVEL_TRACE:
            return "TRACE";
        case LOG_LEVEL_DEBUG:
            return ("DEBUG");
        case LOG_LEVEL_INFO:
            return "INFO";
        case LOG_LEVEL_WARN:
            return CONFIG_PARAMS.warnLevelString;
        case LOG_LEVEL_ERROR:
            return "ERROR";
        }
        throw new IllegalStateException("Unrecognized level [" + level + "]");
    }

    void write(StringBuilder buf, Throwable t) {
        PrintStream targetStream = CONFIG_PARAMS.outputChoice.getTargetPrintStream();

        targetStream.println(buf.toString());
        writeThrowable(t, targetStream);
        targetStream.flush();
    }

    protected void writeThrowable(Throwable t, PrintStream targetStream) {
        if (t != null) {
            t.printStackTrace(targetStream);
        }
    }

    private String getFormattedDate() {
        Date now = new Date();
        String dateText;
        synchronized (CONFIG_PARAMS.dateFormatter) {
            dateText = CONFIG_PARAMS.dateFormatter.format(now);
        }
        return dateText;
    }

    private String computeShortName() {
        return name.substring(name.lastIndexOf(".") + 1);
    }

    For formatted messages, first substitute arguments and then log.
Params: level – 
format – 
arg1 – 
arg2 – /**
     * For formatted messages, first substitute arguments and then log.
     *
     * @param level
     * @param format
     * @param arg1
     * @param arg2
     */
    private void formatAndLog(int level, String format, Object arg1, Object arg2) {
        if (!isLevelEnabled(level)) {
            return;
        }
        FormattingTuple tp = MessageFormatter.format(format, arg1, arg2);
        log(level, tp.getMessage(), tp.getThrowable());
    }

    For formatted messages, first substitute arguments and then log.
Params: level – 
format – 
arguments – 
           a list of 3 ore more arguments/**
     * For formatted messages, first substitute arguments and then log.
     *
     * @param level
     * @param format
     * @param arguments
     *            a list of 3 ore more arguments
     */
    private void formatAndLog(int level, String format, Object... arguments) {
        if (!isLevelEnabled(level)) {
            return;
        }
        FormattingTuple tp = MessageFormatter.arrayFormat(format, arguments);
        log(level, tp.getMessage(), tp.getThrowable());
    }

    Is the given log level currently enabled?
Params: logLevel – 
           is this level enabled?/**
     * Is the given log level currently enabled?
     *
     * @param logLevel
     *            is this level enabled?
     */
    protected boolean isLevelEnabled(int logLevel) {
        // log level are numerically ordered so can use simple numeric
        // comparison
        return (logLevel >= currentLogLevel);
    }

    Are trace messages currently enabled? /** Are {@code trace} messages currently enabled? */
    public boolean isTraceEnabled() {
        return isLevelEnabled(LOG_LEVEL_TRACE);
    }

    A simple implementation which logs messages of level TRACE according to
the format outlined above.
/**
     * A simple implementation which logs messages of level TRACE according to
     * the format outlined above.
     */
    public void trace(String msg) {
        log(LOG_LEVEL_TRACE, msg, null);
    }

    Perform single parameter substitution before logging the message of level
TRACE according to the format outlined above.
/**
     * Perform single parameter substitution before logging the message of level
     * TRACE according to the format outlined above.
     */
    public void trace(String format, Object param1) {
        formatAndLog(LOG_LEVEL_TRACE, format, param1, null);
    }

    Perform double parameter substitution before logging the message of level
TRACE according to the format outlined above.
/**
     * Perform double parameter substitution before logging the message of level
     * TRACE according to the format outlined above.
     */
    public void trace(String format, Object param1, Object param2) {
        formatAndLog(LOG_LEVEL_TRACE, format, param1, param2);
    }

    Perform double parameter substitution before logging the message of level
TRACE according to the format outlined above.
/**
     * Perform double parameter substitution before logging the message of level
     * TRACE according to the format outlined above.
     */
    public void trace(String format, Object... argArray) {
        formatAndLog(LOG_LEVEL_TRACE, format, argArray);
    }

    Log a message of level TRACE, including an exception. /** Log a message of level TRACE, including an exception. */
    public void trace(String msg, Throwable t) {
        log(LOG_LEVEL_TRACE, msg, t);
    }

    Are debug messages currently enabled? /** Are {@code debug} messages currently enabled? */
    public boolean isDebugEnabled() {
        return isLevelEnabled(LOG_LEVEL_DEBUG);
    }

    A simple implementation which logs messages of level DEBUG according to
the format outlined above.
/**
     * A simple implementation which logs messages of level DEBUG according to
     * the format outlined above.
     */
    public void debug(String msg) {
        log(LOG_LEVEL_DEBUG, msg, null);
    }

    Perform single parameter substitution before logging the message of level
DEBUG according to the format outlined above.
/**
     * Perform single parameter substitution before logging the message of level
     * DEBUG according to the format outlined above.
     */
    public void debug(String format, Object param1) {
        formatAndLog(LOG_LEVEL_DEBUG, format, param1, null);
    }

    Perform double parameter substitution before logging the message of level
DEBUG according to the format outlined above.
/**
     * Perform double parameter substitution before logging the message of level
     * DEBUG according to the format outlined above.
     */
    public void debug(String format, Object param1, Object param2) {
        formatAndLog(LOG_LEVEL_DEBUG, format, param1, param2);
    }

    Perform double parameter substitution before logging the message of level
DEBUG according to the format outlined above.
/**
     * Perform double parameter substitution before logging the message of level
     * DEBUG according to the format outlined above.
     */
    public void debug(String format, Object... argArray) {
        formatAndLog(LOG_LEVEL_DEBUG, format, argArray);
    }

    Log a message of level DEBUG, including an exception. /** Log a message of level DEBUG, including an exception. */
    public void debug(String msg, Throwable t) {
        log(LOG_LEVEL_DEBUG, msg, t);
    }

    Are info messages currently enabled? /** Are {@code info} messages currently enabled? */
    public boolean isInfoEnabled() {
        return isLevelEnabled(LOG_LEVEL_INFO);
    }

    A simple implementation which logs messages of level INFO according to
the format outlined above.
/**
     * A simple implementation which logs messages of level INFO according to
     * the format outlined above.
     */
    public void info(String msg) {
        log(LOG_LEVEL_INFO, msg, null);
    }

    Perform single parameter substitution before logging the message of level
INFO according to the format outlined above.
/**
     * Perform single parameter substitution before logging the message of level
     * INFO according to the format outlined above.
     */
    public void info(String format, Object arg) {
        formatAndLog(LOG_LEVEL_INFO, format, arg, null);
    }

    Perform double parameter substitution before logging the message of level
INFO according to the format outlined above.
/**
     * Perform double parameter substitution before logging the message of level
     * INFO according to the format outlined above.
     */
    public void info(String format, Object arg1, Object arg2) {
        formatAndLog(LOG_LEVEL_INFO, format, arg1, arg2);
    }

    Perform double parameter substitution before logging the message of level
INFO according to the format outlined above.
/**
     * Perform double parameter substitution before logging the message of level
     * INFO according to the format outlined above.
     */
    public void info(String format, Object... argArray) {
        formatAndLog(LOG_LEVEL_INFO, format, argArray);
    }

    Log a message of level INFO, including an exception. /** Log a message of level INFO, including an exception. */
    public void info(String msg, Throwable t) {
        log(LOG_LEVEL_INFO, msg, t);
    }

    Are warn messages currently enabled? /** Are {@code warn} messages currently enabled? */
    public boolean isWarnEnabled() {
        return isLevelEnabled(LOG_LEVEL_WARN);
    }

    A simple implementation which always logs messages of level WARN
according to the format outlined above.
/**
     * A simple implementation which always logs messages of level WARN
     * according to the format outlined above.
     */
    public void warn(String msg) {
        log(LOG_LEVEL_WARN, msg, null);
    }

    Perform single parameter substitution before logging the message of level
WARN according to the format outlined above.
/**
     * Perform single parameter substitution before logging the message of level
     * WARN according to the format outlined above.
     */
    public void warn(String format, Object arg) {
        formatAndLog(LOG_LEVEL_WARN, format, arg, null);
    }

    Perform double parameter substitution before logging the message of level
WARN according to the format outlined above.
/**
     * Perform double parameter substitution before logging the message of level
     * WARN according to the format outlined above.
     */
    public void warn(String format, Object arg1, Object arg2) {
        formatAndLog(LOG_LEVEL_WARN, format, arg1, arg2);
    }

    Perform double parameter substitution before logging the message of level
WARN according to the format outlined above.
/**
     * Perform double parameter substitution before logging the message of level
     * WARN according to the format outlined above.
     */
    public void warn(String format, Object... argArray) {
        formatAndLog(LOG_LEVEL_WARN, format, argArray);
    }

    Log a message of level WARN, including an exception. /** Log a message of level WARN, including an exception. */
    public void warn(String msg, Throwable t) {
        log(LOG_LEVEL_WARN, msg, t);
    }

    Are error messages currently enabled? /** Are {@code error} messages currently enabled? */
    public boolean isErrorEnabled() {
        return isLevelEnabled(LOG_LEVEL_ERROR);
    }

    A simple implementation which always logs messages of level ERROR
according to the format outlined above.
/**
     * A simple implementation which always logs messages of level ERROR
     * according to the format outlined above.
     */
    public void error(String msg) {
        log(LOG_LEVEL_ERROR, msg, null);
    }

    Perform single parameter substitution before logging the message of level
ERROR according to the format outlined above.
/**
     * Perform single parameter substitution before logging the message of level
     * ERROR according to the format outlined above.
     */
    public void error(String format, Object arg) {
        formatAndLog(LOG_LEVEL_ERROR, format, arg, null);
    }

    Perform double parameter substitution before logging the message of level
ERROR according to the format outlined above.
/**
     * Perform double parameter substitution before logging the message of level
     * ERROR according to the format outlined above.
     */
    public void error(String format, Object arg1, Object arg2) {
        formatAndLog(LOG_LEVEL_ERROR, format, arg1, arg2);
    }

    Perform double parameter substitution before logging the message of level
ERROR according to the format outlined above.
/**
     * Perform double parameter substitution before logging the message of level
     * ERROR according to the format outlined above.
     */
    public void error(String format, Object... argArray) {
        formatAndLog(LOG_LEVEL_ERROR, format, argArray);
    }

    Log a message of level ERROR, including an exception. /** Log a message of level ERROR, including an exception. */
    public void error(String msg, Throwable t) {
        log(LOG_LEVEL_ERROR, msg, t);
    }

    public void log(LoggingEvent event) {
        int levelInt = event.getLevel().toInt();

        if (!isLevelEnabled(levelInt)) {
            return;
        }
        FormattingTuple tp = MessageFormatter.arrayFormat(event.getMessage(), event.getArgumentArray(), event.getThrowable());
        log(levelInt, tp.getMessage(), event.getThrowable());
    }

}
/

org.slf4j/ slf4j-simple/ 1.7.26/ org/slf4j/impl/SimpleLogger.java
