001/**
002 * Copyright (c) 2004-2011 QOS.ch
003 * All rights reserved.
004 *
005 * Permission is hereby granted, free  of charge, to any person obtaining
006 * a  copy  of this  software  and  associated  documentation files  (the
007 * "Software"), to  deal in  the Software without  restriction, including
008 * without limitation  the rights to  use, copy, modify,  merge, publish,
009 * distribute,  sublicense, and/or sell  copies of  the Software,  and to
010 * permit persons to whom the Software  is furnished to do so, subject to
011 * the following conditions:
012 *
013 * The  above  copyright  notice  and  this permission  notice  shall  be
014 * included in all copies or substantial portions of the Software.
015 *
016 * THE  SOFTWARE IS  PROVIDED  "AS  IS", WITHOUT  WARRANTY  OF ANY  KIND,
017 * EXPRESS OR  IMPLIED, INCLUDING  BUT NOT LIMITED  TO THE  WARRANTIES OF
018 * MERCHANTABILITY,    FITNESS    FOR    A   PARTICULAR    PURPOSE    AND
019 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
020 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
021 * OF CONTRACT, TORT OR OTHERWISE,  ARISING FROM, OUT OF OR IN CONNECTION
022 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
023 *
024 */
025
026package org.slf4j;
027
028/**
029 * The org.slf4j.Logger interface is the main user entry point of SLF4J API.
030 * It is expected that logging takes place through concrete implementations
031 * of this interface.
032 * <p/>
033 * <h3>Typical usage pattern:</h3>
034 * <pre>
035 * import org.slf4j.Logger;
036 * import org.slf4j.LoggerFactory;
037 *
038 * public class Wombat {
039 *
040 *   <span style="color:green">final static Logger logger = LoggerFactory.getLogger(Wombat.class);</span>
041 *   Integer t;
042 *   Integer oldT;
043 *
044 *   public void setTemperature(Integer temperature) {
045 *     oldT = t;
046 *     t = temperature;
047 *     <span style="color:green">logger.debug("Temperature set to {}. Old temperature was {}.", t, oldT);</span>
048 *     if(temperature.intValue() > 50) {
049 *       <span style="color:green">logger.info("Temperature has risen above 50 degrees.");</span>
050 *     }
051 *   }
052 * }
053 * </pre>
054 *
055 * Be sure to read the FAQ entry relating to <a href="../../../faq.html#logging_performance">parameterized
056 * logging</a>. Note that logging statements can be parameterized in
057 * <a href="../../../faq.html#paramException">presence of an exception/throwable</a>.
058 *
059 * <p>Once you are comfortable using loggers, i.e. instances of this interface, consider using
060 * <a href="MDC.html">MDC</a> as well as <a href="Marker.html">Markers</a>.</p>
061 *
062 * @author Ceki G&uuml;lc&uuml;
063 */
064public interface Logger {
065
066    /**
067     * Case insensitive String constant used to retrieve the name of the root logger.
068     *
069     * @since 1.3
070     */
071    final public String ROOT_LOGGER_NAME = "ROOT";
072
073    /**
074     * Return the name of this <code>Logger</code> instance.
075     * @return name of this logger instance 
076     */
077    public String getName();
078
079    /**
080     * Is the logger instance enabled for the TRACE level?
081     *
082     * @return True if this Logger is enabled for the TRACE level,
083     *         false otherwise.
084     * @since 1.4
085     */
086    public boolean isTraceEnabled();
087
088    /**
089     * Log a message at the TRACE level.
090     *
091     * @param msg the message string to be logged
092     * @since 1.4
093     */
094    public void trace(String msg);
095
096    /**
097     * Log a message at the TRACE level according to the specified format
098     * and argument.
099     * <p/>
100     * <p>This form avoids superfluous object creation when the logger
101     * is disabled for the TRACE level. </p>
102     *
103     * @param format the format string
104     * @param arg    the argument
105     * @since 1.4
106     */
107    public void trace(String format, Object arg);
108
109    /**
110     * Log a message at the TRACE level according to the specified format
111     * and arguments.
112     * <p/>
113     * <p>This form avoids superfluous object creation when the logger
114     * is disabled for the TRACE level. </p>
115     *
116     * @param format the format string
117     * @param arg1   the first argument
118     * @param arg2   the second argument
119     * @since 1.4
120     */
121    public void trace(String format, Object arg1, Object arg2);
122
123    /**
124     * Log a message at the TRACE level according to the specified format
125     * and arguments.
126     * <p/>
127     * <p>This form avoids superfluous string concatenation when the logger
128     * is disabled for the TRACE level. However, this variant incurs the hidden
129     * (and relatively small) cost of creating an <code>Object[]</code> before invoking the method,
130     * even if this logger is disabled for TRACE. The variants taking {@link #trace(String, Object) one} and
131     * {@link #trace(String, Object, Object) two} arguments exist solely in order to avoid this hidden cost.</p>
132     *
133     * @param format    the format string
134     * @param arguments a list of 3 or more arguments
135     * @since 1.4
136     */
137    public void trace(String format, Object... arguments);
138
139    /**
140     * Log an exception (throwable) at the TRACE level with an
141     * accompanying message.
142     *
143     * @param msg the message accompanying the exception
144     * @param t   the exception (throwable) to log
145     * @since 1.4
146     */
147    public void trace(String msg, Throwable t);
148
149    /**
150     * Similar to {@link #isTraceEnabled()} method except that the
151     * marker data is also taken into account.
152     *
153     * @param marker The marker data to take into consideration
154     * @return True if this Logger is enabled for the TRACE level,
155     *         false otherwise.
156     *         
157     * @since 1.4
158     */
159    public boolean isTraceEnabled(Marker marker);
160
161    /**
162     * Log a message with the specific Marker at the TRACE level.
163     *
164     * @param marker the marker data specific to this log statement
165     * @param msg    the message string to be logged
166     * @since 1.4
167     */
168    public void trace(Marker marker, String msg);
169
170    /**
171     * This method is similar to {@link #trace(String, Object)} method except that the
172     * marker data is also taken into consideration.
173     *
174     * @param marker the marker data specific to this log statement
175     * @param format the format string
176     * @param arg    the argument
177     * @since 1.4
178     */
179    public void trace(Marker marker, String format, Object arg);
180
181    /**
182     * This method is similar to {@link #trace(String, Object, Object)}
183     * method except that the marker data is also taken into
184     * consideration.
185     *
186     * @param marker the marker data specific to this log statement
187     * @param format the format string
188     * @param arg1   the first argument
189     * @param arg2   the second argument
190     * @since 1.4
191     */
192    public void trace(Marker marker, String format, Object arg1, Object arg2);
193
194    /**
195     * This method is similar to {@link #trace(String, Object...)}
196     * method except that the marker data is also taken into
197     * consideration.
198     *
199     * @param marker   the marker data specific to this log statement
200     * @param format   the format string
201     * @param argArray an array of arguments
202     * @since 1.4
203     */
204    public void trace(Marker marker, String format, Object... argArray);
205
206    /**
207     * This method is similar to {@link #trace(String, Throwable)} method except that the
208     * marker data is also taken into consideration.
209     *
210     * @param marker the marker data specific to this log statement
211     * @param msg    the message accompanying the exception
212     * @param t      the exception (throwable) to log
213     * @since 1.4
214     */
215    public void trace(Marker marker, String msg, Throwable t);
216
217    /**
218     * Is the logger instance enabled for the DEBUG level?
219     *
220     * @return True if this Logger is enabled for the DEBUG level,
221     *         false otherwise.
222     */
223    public boolean isDebugEnabled();
224
225    /**
226     * Log a message at the DEBUG level.
227     *
228     * @param msg the message string to be logged
229     */
230    public void debug(String msg);
231
232    /**
233     * Log a message at the DEBUG level according to the specified format
234     * and argument.
235     * <p/>
236     * <p>This form avoids superfluous object creation when the logger
237     * is disabled for the DEBUG level. </p>
238     *
239     * @param format the format string
240     * @param arg    the argument
241     */
242    public void debug(String format, Object arg);
243
244    /**
245     * Log a message at the DEBUG level according to the specified format
246     * and arguments.
247     * <p/>
248     * <p>This form avoids superfluous object creation when the logger
249     * is disabled for the DEBUG level. </p>
250     *
251     * @param format the format string
252     * @param arg1   the first argument
253     * @param arg2   the second argument
254     */
255    public void debug(String format, Object arg1, Object arg2);
256
257    /**
258     * Log a message at the DEBUG level according to the specified format
259     * and arguments.
260     * <p/>
261     * <p>This form avoids superfluous string concatenation when the logger
262     * is disabled for the DEBUG level. However, this variant incurs the hidden
263     * (and relatively small) cost of creating an <code>Object[]</code> before invoking the method,
264     * even if this logger is disabled for DEBUG. The variants taking
265     * {@link #debug(String, Object) one} and {@link #debug(String, Object, Object) two}
266     * arguments exist solely in order to avoid this hidden cost.</p>
267     *
268     * @param format    the format string
269     * @param arguments a list of 3 or more arguments
270     */
271    public void debug(String format, Object... arguments);
272
273    /**
274     * Log an exception (throwable) at the DEBUG level with an
275     * accompanying message.
276     *
277     * @param msg the message accompanying the exception
278     * @param t   the exception (throwable) to log
279     */
280    public void debug(String msg, Throwable t);
281
282    /**
283     * Similar to {@link #isDebugEnabled()} method except that the
284     * marker data is also taken into account.
285     *
286     * @param marker The marker data to take into consideration
287     * @return True if this Logger is enabled for the DEBUG level,
288     *         false otherwise. 
289     */
290    public boolean isDebugEnabled(Marker marker);
291
292    /**
293     * Log a message with the specific Marker at the DEBUG level.
294     *
295     * @param marker the marker data specific to this log statement
296     * @param msg    the message string to be logged
297     */
298    public void debug(Marker marker, String msg);
299
300    /**
301     * This method is similar to {@link #debug(String, Object)} method except that the
302     * marker data is also taken into consideration.
303     *
304     * @param marker the marker data specific to this log statement
305     * @param format the format string
306     * @param arg    the argument
307     */
308    public void debug(Marker marker, String format, Object arg);
309
310    /**
311     * This method is similar to {@link #debug(String, Object, Object)}
312     * method except that the marker data is also taken into
313     * consideration.
314     *
315     * @param marker the marker data specific to this log statement
316     * @param format the format string
317     * @param arg1   the first argument
318     * @param arg2   the second argument
319     */
320    public void debug(Marker marker, String format, Object arg1, Object arg2);
321
322    /**
323     * This method is similar to {@link #debug(String, Object...)}
324     * method except that the marker data is also taken into
325     * consideration.
326     *
327     * @param marker    the marker data specific to this log statement
328     * @param format    the format string
329     * @param arguments a list of 3 or more arguments
330     */
331    public void debug(Marker marker, String format, Object... arguments);
332
333    /**
334     * This method is similar to {@link #debug(String, Throwable)} method except that the
335     * marker data is also taken into consideration.
336     *
337     * @param marker the marker data specific to this log statement
338     * @param msg    the message accompanying the exception
339     * @param t      the exception (throwable) to log
340     */
341    public void debug(Marker marker, String msg, Throwable t);
342
343    /**
344     * Is the logger instance enabled for the INFO level?
345     *
346     * @return True if this Logger is enabled for the INFO level,
347     *         false otherwise.
348     */
349    public boolean isInfoEnabled();
350
351    /**
352     * Log a message at the INFO level.
353     *
354     * @param msg the message string to be logged
355     */
356    public void info(String msg);
357
358    /**
359     * Log a message at the INFO level according to the specified format
360     * and argument.
361     * <p/>
362     * <p>This form avoids superfluous object creation when the logger
363     * is disabled for the INFO level. </p>
364     *
365     * @param format the format string
366     * @param arg    the argument
367     */
368    public void info(String format, Object arg);
369
370    /**
371     * Log a message at the INFO level according to the specified format
372     * and arguments.
373     * <p/>
374     * <p>This form avoids superfluous object creation when the logger
375     * is disabled for the INFO level. </p>
376     *
377     * @param format the format string
378     * @param arg1   the first argument
379     * @param arg2   the second argument
380     */
381    public void info(String format, Object arg1, Object arg2);
382
383    /**
384     * Log a message at the INFO level according to the specified format
385     * and arguments.
386     * <p/>
387     * <p>This form avoids superfluous string concatenation when the logger
388     * is disabled for the INFO level. However, this variant incurs the hidden
389     * (and relatively small) cost of creating an <code>Object[]</code> before invoking the method,
390     * even if this logger is disabled for INFO. The variants taking
391     * {@link #info(String, Object) one} and {@link #info(String, Object, Object) two}
392     * arguments exist solely in order to avoid this hidden cost.</p>
393     *
394     * @param format    the format string
395     * @param arguments a list of 3 or more arguments
396     */
397    public void info(String format, Object... arguments);
398
399    /**
400     * Log an exception (throwable) at the INFO level with an
401     * accompanying message.
402     *
403     * @param msg the message accompanying the exception
404     * @param t   the exception (throwable) to log
405     */
406    public void info(String msg, Throwable t);
407
408    /**
409     * Similar to {@link #isInfoEnabled()} method except that the marker
410     * data is also taken into consideration.
411     *
412     * @param marker The marker data to take into consideration
413     * @return true if this logger is warn enabled, false otherwise 
414     */
415    public boolean isInfoEnabled(Marker marker);
416
417    /**
418     * Log a message with the specific Marker at the INFO level.
419     *
420     * @param marker The marker specific to this log statement
421     * @param msg    the message string to be logged
422     */
423    public void info(Marker marker, String msg);
424
425    /**
426     * This method is similar to {@link #info(String, Object)} method except that the
427     * marker data is also taken into consideration.
428     *
429     * @param marker the marker data specific to this log statement
430     * @param format the format string
431     * @param arg    the argument
432     */
433    public void info(Marker marker, String format, Object arg);
434
435    /**
436     * This method is similar to {@link #info(String, Object, Object)}
437     * method except that the marker data is also taken into
438     * consideration.
439     *
440     * @param marker the marker data specific to this log statement
441     * @param format the format string
442     * @param arg1   the first argument
443     * @param arg2   the second argument
444     */
445    public void info(Marker marker, String format, Object arg1, Object arg2);
446
447    /**
448     * This method is similar to {@link #info(String, Object...)}
449     * method except that the marker data is also taken into
450     * consideration.
451     *
452     * @param marker    the marker data specific to this log statement
453     * @param format    the format string
454     * @param arguments a list of 3 or more arguments
455     */
456    public void info(Marker marker, String format, Object... arguments);
457
458    /**
459     * This method is similar to {@link #info(String, Throwable)} method
460     * except that the marker data is also taken into consideration.
461     *
462     * @param marker the marker data for this log statement
463     * @param msg    the message accompanying the exception
464     * @param t      the exception (throwable) to log
465     */
466    public void info(Marker marker, String msg, Throwable t);
467
468    /**
469     * Is the logger instance enabled for the WARN level?
470     *
471     * @return True if this Logger is enabled for the WARN level,
472     *         false otherwise.
473     */
474    public boolean isWarnEnabled();
475
476    /**
477     * Log a message at the WARN level.
478     *
479     * @param msg the message string to be logged
480     */
481    public void warn(String msg);
482
483    /**
484     * Log a message at the WARN level according to the specified format
485     * and argument.
486     * <p/>
487     * <p>This form avoids superfluous object creation when the logger
488     * is disabled for the WARN level. </p>
489     *
490     * @param format the format string
491     * @param arg    the argument
492     */
493    public void warn(String format, Object arg);
494
495    /**
496     * Log a message at the WARN level according to the specified format
497     * and arguments.
498     * <p/>
499     * <p>This form avoids superfluous string concatenation when the logger
500     * is disabled for the WARN level. However, this variant incurs the hidden
501     * (and relatively small) cost of creating an <code>Object[]</code> before invoking the method,
502     * even if this logger is disabled for WARN. The variants taking
503     * {@link #warn(String, Object) one} and {@link #warn(String, Object, Object) two}
504     * arguments exist solely in order to avoid this hidden cost.</p>
505     *
506     * @param format    the format string
507     * @param arguments a list of 3 or more arguments
508     */
509    public void warn(String format, Object... arguments);
510
511    /**
512     * Log a message at the WARN level according to the specified format
513     * and arguments.
514     * <p/>
515     * <p>This form avoids superfluous object creation when the logger
516     * is disabled for the WARN level. </p>
517     *
518     * @param format the format string
519     * @param arg1   the first argument
520     * @param arg2   the second argument
521     */
522    public void warn(String format, Object arg1, Object arg2);
523
524    /**
525     * Log an exception (throwable) at the WARN level with an
526     * accompanying message.
527     *
528     * @param msg the message accompanying the exception
529     * @param t   the exception (throwable) to log
530     */
531    public void warn(String msg, Throwable t);
532
533    /**
534     * Similar to {@link #isWarnEnabled()} method except that the marker
535     * data is also taken into consideration.
536     *
537     * @param marker The marker data to take into consideration
538     * @return True if this Logger is enabled for the WARN level,
539     *         false otherwise.
540     */
541    public boolean isWarnEnabled(Marker marker);
542
543    /**
544     * Log a message with the specific Marker at the WARN level.
545     *
546     * @param marker The marker specific to this log statement
547     * @param msg    the message string to be logged
548     */
549    public void warn(Marker marker, String msg);
550
551    /**
552     * This method is similar to {@link #warn(String, Object)} method except that the
553     * marker data is also taken into consideration.
554     *
555     * @param marker the marker data specific to this log statement
556     * @param format the format string
557     * @param arg    the argument
558     */
559    public void warn(Marker marker, String format, Object arg);
560
561    /**
562     * This method is similar to {@link #warn(String, Object, Object)}
563     * method except that the marker data is also taken into
564     * consideration.
565     *
566     * @param marker the marker data specific to this log statement
567     * @param format the format string
568     * @param arg1   the first argument
569     * @param arg2   the second argument
570     */
571    public void warn(Marker marker, String format, Object arg1, Object arg2);
572
573    /**
574     * This method is similar to {@link #warn(String, Object...)}
575     * method except that the marker data is also taken into
576     * consideration.
577     *
578     * @param marker    the marker data specific to this log statement
579     * @param format    the format string
580     * @param arguments a list of 3 or more arguments
581     */
582    public void warn(Marker marker, String format, Object... arguments);
583
584    /**
585     * This method is similar to {@link #warn(String, Throwable)} method
586     * except that the marker data is also taken into consideration.
587     *
588     * @param marker the marker data for this log statement
589     * @param msg    the message accompanying the exception
590     * @param t      the exception (throwable) to log
591     */
592    public void warn(Marker marker, String msg, Throwable t);
593
594    /**
595     * Is the logger instance enabled for the ERROR level?
596     *
597     * @return True if this Logger is enabled for the ERROR level,
598     *         false otherwise.
599     */
600    public boolean isErrorEnabled();
601
602    /**
603     * Log a message at the ERROR level.
604     *
605     * @param msg the message string to be logged
606     */
607    public void error(String msg);
608
609    /**
610     * Log a message at the ERROR level according to the specified format
611     * and argument.
612     * <p/>
613     * <p>This form avoids superfluous object creation when the logger
614     * is disabled for the ERROR level. </p>
615     *
616     * @param format the format string
617     * @param arg    the argument
618     */
619    public void error(String format, Object arg);
620
621    /**
622     * Log a message at the ERROR level according to the specified format
623     * and arguments.
624     * <p/>
625     * <p>This form avoids superfluous object creation when the logger
626     * is disabled for the ERROR level. </p>
627     *
628     * @param format the format string
629     * @param arg1   the first argument
630     * @param arg2   the second argument
631     */
632    public void error(String format, Object arg1, Object arg2);
633
634    /**
635     * Log a message at the ERROR level according to the specified format
636     * and arguments.
637     * <p/>
638     * <p>This form avoids superfluous string concatenation when the logger
639     * is disabled for the ERROR level. However, this variant incurs the hidden
640     * (and relatively small) cost of creating an <code>Object[]</code> before invoking the method,
641     * even if this logger is disabled for ERROR. The variants taking
642     * {@link #error(String, Object) one} and {@link #error(String, Object, Object) two}
643     * arguments exist solely in order to avoid this hidden cost.</p>
644     *
645     * @param format    the format string
646     * @param arguments a list of 3 or more arguments
647     */
648    public void error(String format, Object... arguments);
649
650    /**
651     * Log an exception (throwable) at the ERROR level with an
652     * accompanying message.
653     *
654     * @param msg the message accompanying the exception
655     * @param t   the exception (throwable) to log
656     */
657    public void error(String msg, Throwable t);
658
659    /**
660     * Similar to {@link #isErrorEnabled()} method except that the
661     * marker data is also taken into consideration.
662     *
663     * @param marker The marker data to take into consideration
664     * @return True if this Logger is enabled for the ERROR level,
665     *         false otherwise.
666     */
667    public boolean isErrorEnabled(Marker marker);
668
669    /**
670     * Log a message with the specific Marker at the ERROR level.
671     *
672     * @param marker The marker specific to this log statement
673     * @param msg    the message string to be logged
674     */
675    public void error(Marker marker, String msg);
676
677    /**
678     * This method is similar to {@link #error(String, Object)} method except that the
679     * marker data is also taken into consideration.
680     *
681     * @param marker the marker data specific to this log statement
682     * @param format the format string
683     * @param arg    the argument
684     */
685    public void error(Marker marker, String format, Object arg);
686
687    /**
688     * This method is similar to {@link #error(String, Object, Object)}
689     * method except that the marker data is also taken into
690     * consideration.
691     *
692     * @param marker the marker data specific to this log statement
693     * @param format the format string
694     * @param arg1   the first argument
695     * @param arg2   the second argument
696     */
697    public void error(Marker marker, String format, Object arg1, Object arg2);
698
699    /**
700     * This method is similar to {@link #error(String, Object...)}
701     * method except that the marker data is also taken into
702     * consideration.
703     *
704     * @param marker    the marker data specific to this log statement
705     * @param format    the format string
706     * @param arguments a list of 3 or more arguments
707     */
708    public void error(Marker marker, String format, Object... arguments);
709
710    /**
711     * This method is similar to {@link #error(String, Throwable)}
712     * method except that the marker data is also taken into
713     * consideration.
714     *
715     * @param marker the marker data specific to this log statement
716     * @param msg    the message accompanying the exception
717     * @param t      the exception (throwable) to log
718     */
719    public void error(Marker marker, String msg, Throwable t);
720
721}