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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one
3    * or more contributor license agreements.  See the NOTICE file
4    * distributed with this work for additional information
5    * regarding copyright ownership.  The ASF licenses this file
6    * to you under the Apache License, Version 2.0 (the
7    * "License"); you may not use this file except in compliance
8    * with the License.  You may obtain a copy of the License at
9    *
10   *   http://www.apache.org/licenses/LICENSE-2.0
11   *
12   * Unless required by applicable law or agreed to in writing,
13   * software distributed under the License is distributed on an
14   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15   * KIND, either express or implied.  See the License for the
16   * specific language governing permissions and limitations
17   * under the License.
18   */
19  package org.apache.maven.slf4j;
20  
21  import java.io.PrintStream;
22  import java.time.Clock;
23  import java.time.Duration;
24  import java.time.Instant;
25  import java.util.ArrayList;
26  import java.util.List;
27  
28  import org.apache.maven.api.MonotonicClock;
29  import org.slf4j.Logger;
30  import org.slf4j.Marker;
31  import org.slf4j.event.Level;
32  import org.slf4j.event.LoggingEvent;
33  import org.slf4j.helpers.LegacyAbstractLogger;
34  import org.slf4j.helpers.MessageFormatter;
35  import org.slf4j.helpers.NormalizedParameters;
36  import org.slf4j.spi.LocationAwareLogger;
37  
38  /**
39   * <p>
40   * Simple implementation of {@link Logger} that sends all enabled log messages,
41   * for all defined loggers, to the console ({@code System.err}). The following
42   * system properties are supported to configure the behavior of this logger:
43   *
44   *
45   * <ul>
46   * <li><code>org.slf4j.simpleLogger.logFile</code> - The output target which can
47   * be the <em>path</em> to a file, or the special values "System.out" and
48   * "System.err". Default is "System.err".</li>
49   *
50   * <li><code>org.slf4j.simpleLogger.cacheOutputStream</code> - If the output
51   * target is set to "System.out" or "System.err" (see preceding entry), by
52   * default, logs will be output to the latest value referenced by
53   * <code>System.out/err</code> variables. By setting this parameter to true, the
54   * output stream will be cached, i.e. assigned once at initialization time and
55   * re-used independently of the current value referenced by
56   * <code>System.out/err</code>.</li>
57   *
58   * <li><code>org.slf4j.simpleLogger.defaultLogLevel</code> - Default log level
59   * for all instances of SimpleLogger. Must be one of ("trace", "debug", "info",
60   * "warn", "error" or "off"). If not specified, defaults to "info".</li>
61   *
62   * <li><code>org.slf4j.simpleLogger.log.<em>a.b.c</em></code> - Logging detail
63   * level for a SimpleLogger instance named "a.b.c". Right-side value must be one
64   * of "trace", "debug", "info", "warn", "error" or "off". When a SimpleLogger
65   * named "a.b.c" is initialized, its level is assigned from this property. If
66   * unspecified, the level of nearest parent logger will be used, and if none is
67   * set, then the value specified by
68   * <code>org.slf4j.simpleLogger.defaultLogLevel</code> will be used.</li>
69   *
70   * <li><code>org.slf4j.simpleLogger.showDateTime</code> - Set to
71   * <code>true</code> if you want the current date and time to be included in
72   * output messages. Default is <code>false</code></li>
73   *
74   * <li><code>org.slf4j.simpleLogger.dateTimeFormat</code> - The date and time
75   * format to be used in the output messages. The pattern describing the date and
76   * time format is defined by <a href=
77   * "http://docs.oracle.com/javase/1.5.0/docs/api/java/text/SimpleDateFormat.html">
78   * <code>SimpleDateFormat</code></a>. If the format is not specified or is
79   * invalid, the number of milliseconds since start up will be output.</li>
80   *
81   * <li><code>org.slf4j.simpleLogger.showThreadName</code> -Set to
82   * <code>true</code> if you want to output the current thread name. Defaults to
83   * <code>true</code>.</li>
84   *
85   * <li>(since version 1.7.33 and 2.0.0-alpha6) <code>org.slf4j.simpleLogger.showThreadId</code> -
86   * If you would like to output the current thread id, then set to
87   * <code>true</code>. Defaults to <code>false</code>.</li>
88   *
89   * <li><code>org.slf4j.simpleLogger.showLogName</code> - Set to
90   * <code>true</code> if you want the Logger instance name to be included in
91   * output messages. Defaults to <code>true</code>.</li>
92   *
93   * <li><code>org.slf4j.simpleLogger.showShortLogName</code> - Set to
94   * <code>true</code> if you want the last component of the name to be included
95   * in output messages. Defaults to <code>false</code>.</li>
96   *
97   * <li><code>org.slf4j.simpleLogger.levelInBrackets</code> - Should the level
98   * string be output in brackets? Defaults to <code>false</code>.</li>
99   *
100  * <li><code>org.slf4j.simpleLogger.warnLevelString</code> - The string value
101  * output for the warn level. Defaults to <code>WARN</code>.</li>
102  *
103  * </ul>
104  *
105  * <p>
106  * In addition to looking for system properties with the names specified above,
107  * this implementation also checks for a class loader resource named
108  * <code>"simplelogger.properties"</code>, and includes any matching definitions
109  * from this resource (if it exists).
110  *
111  *
112  * <p>
113  * With no configuration, the default output includes the relative time in
114  * milliseconds, thread name, the level, logger name, and the message followed
115  * by the line separator for the host. In log4j terms it amounts to the "%r [%t]
116  * %level %logger - %m%n" pattern.
117  *
118  * <p>
119  * Sample output follows.
120  *
121  *
122  * <pre>
123  * 176 [main] INFO examples.Sort - Populating an array of 2 elements in reverse order.
124  * 225 [main] INFO examples.SortAlgo - Entered the sort method.
125  * 304 [main] INFO examples.SortAlgo - Dump of integer array:
126  * 317 [main] INFO examples.SortAlgo - Element [0] = 0
127  * 331 [main] INFO examples.SortAlgo - Element [1] = 1
128  * 343 [main] INFO examples.Sort - The next log statement should be an error message.
129  * 346 [main] ERROR examples.SortAlgo - Tried to dump an uninitialized array.
130  *   at org.log4j.examples.SortAlgo.dump(SortAlgo.java:58)
131  *   at org.log4j.examples.Sort.main(Sort.java:64)
132  * 467 [main] INFO  examples.Sort - Exiting main method.
133  * </pre>
134  *
135  * <p>
136  * This implementation is heavily inspired by
137  * <a href="http://commons.apache.org/logging/">Apache Commons Logging</a>'s
138  * SimpleLog.
139  *
140  *
141  * @author Ceki G&uuml;lc&uuml;
142  * @author Scott Sanders
143  * @author Rod Waldhoff
144  * @author Robert Burrell Donkin
145  * @author C&eacute;drik LIME
146  */
147 public class MavenBaseLogger extends LegacyAbstractLogger {
148 
149     private static final long serialVersionUID = -632788891211436180L;
150 
151     private static final Clock MONOTONIC_CLOCK = Clock.tick(Clock.systemUTC(), Duration.ofMillis(1));
152     private static final Instant START_TIME = MonotonicClock.now();
153 
154     protected static final int LOG_LEVEL_TRACE = LocationAwareLogger.TRACE_INT;
155     protected static final int LOG_LEVEL_DEBUG = LocationAwareLogger.DEBUG_INT;
156     protected static final int LOG_LEVEL_INFO = LocationAwareLogger.INFO_INT;
157     protected static final int LOG_LEVEL_WARN = LocationAwareLogger.WARN_INT;
158     protected static final int LOG_LEVEL_ERROR = LocationAwareLogger.ERROR_INT;
159 
160     static final char SP = ' ';
161     static final String TID_PREFIX = "tid=";
162 
163     // The OFF level can only be used in configuration files to disable logging.
164     // It has
165     // no printing method associated with it in o.s.Logger interface.
166     protected static final int LOG_LEVEL_OFF = LOG_LEVEL_ERROR + 10;
167 
168     static final SimpleLoggerConfiguration CONFIG_PARAMS = new SimpleLoggerConfiguration();
169 
170     private static boolean initialized = false;
171 
172     static void lazyInit() {
173         if (initialized) {
174             return;
175         }
176         initialized = true;
177         init();
178     }
179 
180     // external software might be invoking this method directly. Do not rename
181     // or change its semantics.
182     static void init() {
183         CONFIG_PARAMS.init();
184     }
185 
186     /** The current log level */
187     protected int currentLogLevel = LOG_LEVEL_INFO;
188     /** The short name of this simple log instance */
189     private transient String shortLogName = null;
190 
191     /**
192      * All system properties used by <code>SimpleLogger</code> start with this
193      * prefix
194      */
195     public static final String SYSTEM_PREFIX = "org.slf4j.simpleLogger.";
196 
197     public static final String LOG_KEY_PREFIX = MavenBaseLogger.SYSTEM_PREFIX + "log.";
198 
199     public static final String CACHE_OUTPUT_STREAM_STRING_KEY = MavenBaseLogger.SYSTEM_PREFIX + "cacheOutputStream";
200 
201     public static final String WARN_LEVEL_STRING_KEY = MavenBaseLogger.SYSTEM_PREFIX + "warnLevelString";
202 
203     public static final String LEVEL_IN_BRACKETS_KEY = MavenBaseLogger.SYSTEM_PREFIX + "levelInBrackets";
204 
205     public static final String LOG_FILE_KEY = MavenBaseLogger.SYSTEM_PREFIX + "logFile";
206 
207     public static final String SHOW_SHORT_LOG_NAME_KEY = MavenBaseLogger.SYSTEM_PREFIX + "showShortLogName";
208 
209     public static final String SHOW_LOG_NAME_KEY = MavenBaseLogger.SYSTEM_PREFIX + "showLogName";
210 
211     public static final String SHOW_THREAD_NAME_KEY = MavenBaseLogger.SYSTEM_PREFIX + "showThreadName";
212 
213     public static final String SHOW_THREAD_ID_KEY = MavenBaseLogger.SYSTEM_PREFIX + "showThreadId";
214 
215     public static final String DATE_TIME_FORMAT_KEY = MavenBaseLogger.SYSTEM_PREFIX + "dateTimeFormat";
216 
217     public static final String SHOW_DATE_TIME_KEY = MavenBaseLogger.SYSTEM_PREFIX + "showDateTime";
218 
219     public static final String DEFAULT_LOG_LEVEL_KEY = MavenBaseLogger.SYSTEM_PREFIX + "defaultLogLevel";
220 
221     /**
222      * Protected access allows only {@link MavenLoggerFactory} and also derived classes to instantiate
223      * MavenLoggerFactory instances.
224      */
225     protected MavenBaseLogger(String name) {
226         this.name = name;
227 
228         String levelString = recursivelyComputeLevelString();
229         if (levelString != null) {
230             this.currentLogLevel = SimpleLoggerConfiguration.stringToLevel(levelString);
231         } else {
232             this.currentLogLevel = CONFIG_PARAMS.defaultLogLevel;
233         }
234     }
235 
236     String recursivelyComputeLevelString() {
237         String tempName = name;
238         String levelString = null;
239         int indexOfLastDot = tempName.length();
240         while ((levelString == null) && (indexOfLastDot > -1)) {
241             tempName = tempName.substring(0, indexOfLastDot);
242             levelString = CONFIG_PARAMS.getStringProperty(MavenBaseLogger.LOG_KEY_PREFIX + tempName, null);
243             indexOfLastDot = String.valueOf(tempName).lastIndexOf(".");
244         }
245         return levelString;
246     }
247 
248     /**
249      * To avoid intermingling of log messages and associated stack traces, the two
250      * operations are done in a synchronized block.
251      *
252      * @param buf
253      * @param t
254      */
255     protected void write(StringBuilder buf, Throwable t) {
256         PrintStream targetStream = CONFIG_PARAMS.outputChoice.getTargetPrintStream();
257 
258         synchronized (CONFIG_PARAMS) {
259             targetStream.println(buf.toString());
260             writeThrowable(t, targetStream);
261             targetStream.flush();
262         }
263     }
264 
265     protected void writeThrowable(Throwable t, PrintStream targetStream) {
266         if (t != null) {
267             t.printStackTrace(targetStream);
268         }
269     }
270 
271     protected String getFormattedDate() {
272         Instant now = MonotonicClock.now();
273         String dateText;
274         synchronized (CONFIG_PARAMS.dateFormatter) {
275             dateText = CONFIG_PARAMS.dateFormatter.format(now);
276         }
277         return dateText;
278     }
279 
280     protected String computeShortName() {
281         return name.substring(name.lastIndexOf(".") + 1);
282     }
283 
284     // /**
285     // * For formatted messages, first substitute arguments and then log.
286     // *
287     // * @param level
288     // * @param format
289     // * @param arg1
290     // * @param arg2
291     // */
292     // private void formatAndLog(int level, String format, Object arg1, Object arg2) {
293     // if (!isLevelEnabled(level)) {
294     // return;
295     // }
296     // FormattingTuple tp = MessageFormatter.format(format, arg1, arg2);
297     // log(level, tp.getMessage(), tp.getThrowable());
298     // }
299 
300     // /**
301     // * For formatted messages, first substitute arguments and then log.
302     // *
303     // * @param level
304     // * @param format
305     // * @param arguments
306     // * a list of 3 ore more arguments
307     // */
308     // private void formatAndLog(int level, String format, Object... arguments) {
309     // if (!isLevelEnabled(level)) {
310     // return;
311     // }
312     // FormattingTuple tp = MessageFormatter.arrayFormat(format, arguments);
313     // log(level, tp.getMessage(), tp.getThrowable());
314     // }
315 
316     /**
317      * Is the given log level currently enabled?
318      *
319      * @param logLevel is this level enabled?
320      * @return whether the logger is enabled for the given level
321      */
322     protected boolean isLevelEnabled(int logLevel) {
323         // log level are numerically ordered so can use simple numeric
324         // comparison
325         return (logLevel >= currentLogLevel);
326     }
327 
328     /** Are {@code trace} messages currently enabled? */
329     public boolean isTraceEnabled() {
330         return isLevelEnabled(LOG_LEVEL_TRACE);
331     }
332 
333     /** Are {@code debug} messages currently enabled? */
334     public boolean isDebugEnabled() {
335         return isLevelEnabled(LOG_LEVEL_DEBUG);
336     }
337 
338     /** Are {@code info} messages currently enabled? */
339     public boolean isInfoEnabled() {
340         return isLevelEnabled(LOG_LEVEL_INFO);
341     }
342 
343     /** Are {@code warn} messages currently enabled? */
344     public boolean isWarnEnabled() {
345         return isLevelEnabled(LOG_LEVEL_WARN);
346     }
347 
348     /** Are {@code error} messages currently enabled? */
349     public boolean isErrorEnabled() {
350         return isLevelEnabled(LOG_LEVEL_ERROR);
351     }
352 
353     /**
354      * SimpleLogger's implementation of
355      * {@link org.slf4j.helpers.AbstractLogger#handleNormalizedLoggingCall(Level, Marker, String, Object[], Throwable) AbstractLogger#handleNormalizedLoggingCall}
356      * }
357      *
358      * @param level the SLF4J level for this event
359      * @param marker  The marker to be used for this event, may be null.
360      * @param messagePattern The message pattern which will be parsed and formatted
361      * @param arguments  the array of arguments to be formatted, may be null
362      * @param throwable  The exception whose stack trace should be logged, may be null
363      */
364     @Override
365     protected void handleNormalizedLoggingCall(
366             Level level, Marker marker, String messagePattern, Object[] arguments, Throwable throwable) {
367 
368         List<Marker> markers = null;
369 
370         if (marker != null) {
371             markers = new ArrayList<>();
372             markers.add(marker);
373         }
374 
375         innerHandleNormalizedLoggingCall(level, markers, messagePattern, arguments, throwable);
376     }
377 
378     private void innerHandleNormalizedLoggingCall(
379             Level level, List<Marker> markers, String messagePattern, Object[] arguments, Throwable t) {
380 
381         StringBuilder buf = new StringBuilder(32);
382 
383         // Append date-time if so configured
384         if (CONFIG_PARAMS.showDateTime) {
385             if (CONFIG_PARAMS.dateFormatter != null) {
386                 buf.append(getFormattedDate());
387                 buf.append(SP);
388             } else {
389                 buf.append(Duration.between(START_TIME, MonotonicClock.now()).toMillis());
390                 buf.append(SP);
391             }
392         }
393 
394         // Append current thread name if so configured
395         if (CONFIG_PARAMS.showThreadName) {
396             buf.append('[');
397             buf.append(Thread.currentThread().getName());
398             buf.append("] ");
399         }
400 
401         if (CONFIG_PARAMS.showThreadId) {
402             buf.append(TID_PREFIX);
403             buf.append(Thread.currentThread().getId());
404             buf.append(SP);
405         }
406 
407         if (CONFIG_PARAMS.levelInBrackets) {
408             buf.append('[');
409         }
410 
411         // Append a readable representation of the log level
412         String levelStr = renderLevel(level.toInt());
413         buf.append(levelStr);
414         if (CONFIG_PARAMS.levelInBrackets) {
415             buf.append(']');
416         }
417         buf.append(SP);
418 
419         // Append the name of the log instance if so configured
420         if (CONFIG_PARAMS.showShortLogName) {
421             if (shortLogName == null) {
422                 shortLogName = computeShortName();
423             }
424             buf.append(shortLogName).append(" - ");
425         } else if (CONFIG_PARAMS.showLogName) {
426             buf.append(name).append(" - ");
427         }
428 
429         if (markers != null) {
430             buf.append(SP);
431             for (Marker marker : markers) {
432                 buf.append(marker.getName()).append(SP);
433             }
434         }
435 
436         String formattedMessage = MessageFormatter.basicArrayFormat(messagePattern, arguments);
437 
438         // Append the message
439         buf.append(formattedMessage);
440 
441         write(buf, t);
442     }
443 
444     protected String renderLevel(int levelInt) {
445         switch (levelInt) {
446             case LOG_LEVEL_TRACE:
447                 return "TRACE";
448             case LOG_LEVEL_DEBUG:
449                 return ("DEBUG");
450             case LOG_LEVEL_INFO:
451                 return "INFO";
452             case LOG_LEVEL_WARN:
453                 return "WARN";
454             case LOG_LEVEL_ERROR:
455                 return "ERROR";
456             default:
457                 throw new IllegalStateException("Unrecognized level [" + levelInt + "]");
458         }
459     }
460 
461     public void log(LoggingEvent event) {
462         int levelInt = event.getLevel().toInt();
463 
464         if (!isLevelEnabled(levelInt)) {
465             return;
466         }
467 
468         NormalizedParameters np = NormalizedParameters.normalize(event);
469 
470         innerHandleNormalizedLoggingCall(
471                 event.getLevel(), event.getMarkers(), np.getMessage(), np.getArguments(), event.getThrowable());
472     }
473 
474     @Override
475     protected String getFullyQualifiedCallerName() {
476         return null;
477     }
478 }