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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements. See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache license, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License. You may obtain a copy of the License at
8    *
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the license for the specific language governing permissions and
15   * limitations under the license.
16   */
17  package org.apache.logging.log4j.core.config;
18  
19  import java.util.ArrayList;
20  import java.util.Arrays;
21  import java.util.Collections;
22  import java.util.HashMap;
23  import java.util.List;
24  import java.util.Map;
25  
26  import org.apache.logging.log4j.Level;
27  import org.apache.logging.log4j.LogManager;
28  import org.apache.logging.log4j.Marker;
29  import org.apache.logging.log4j.core.Appender;
30  import org.apache.logging.log4j.core.Core;
31  import org.apache.logging.log4j.core.Filter;
32  import org.apache.logging.log4j.core.LogEvent;
33  import org.apache.logging.log4j.core.LoggerContext;
34  import org.apache.logging.log4j.core.async.AsyncLoggerConfig;
35  import org.apache.logging.log4j.core.async.AsyncLoggerContext;
36  import org.apache.logging.log4j.core.async.AsyncLoggerContextSelector;
37  import org.apache.logging.log4j.core.config.plugins.Plugin;
38  import org.apache.logging.log4j.core.config.plugins.PluginAttribute;
39  import org.apache.logging.log4j.core.config.plugins.PluginConfiguration;
40  import org.apache.logging.log4j.core.config.plugins.PluginElement;
41  import org.apache.logging.log4j.core.config.plugins.PluginFactory;
42  import org.apache.logging.log4j.core.config.plugins.validation.constraints.Required;
43  import org.apache.logging.log4j.core.filter.AbstractFilterable;
44  import org.apache.logging.log4j.core.impl.DefaultLogEventFactory;
45  import org.apache.logging.log4j.core.impl.LocationAware;
46  import org.apache.logging.log4j.core.impl.LocationAwareLogEventFactory;
47  import org.apache.logging.log4j.core.impl.Log4jLogEvent;
48  import org.apache.logging.log4j.core.impl.LogEventFactory;
49  import org.apache.logging.log4j.core.impl.ReusableLogEventFactory;
50  import org.apache.logging.log4j.core.lookup.StrSubstitutor;
51  import org.apache.logging.log4j.core.util.Booleans;
52  import org.apache.logging.log4j.core.util.Constants;
53  import org.apache.logging.log4j.core.util.Loader;
54  import org.apache.logging.log4j.message.Message;
55  import org.apache.logging.log4j.util.PerformanceSensitive;
56  import org.apache.logging.log4j.util.PropertiesUtil;
57  import org.apache.logging.log4j.util.StackLocatorUtil;
58  import org.apache.logging.log4j.util.Strings;
59  
60  /**
61   * Logger object that is created via configuration.
62   */
63  @Plugin(name = "logger", category = Node.CATEGORY, printObject = true)
64  public class LoggerConfig extends AbstractFilterable implements LocationAware {
65  
66      public static final String ROOT = "root";
67      private static LogEventFactory LOG_EVENT_FACTORY = null;
68  
69      private List<AppenderRef> appenderRefs = new ArrayList<>();
70      private final AppenderControlArraySet appenders = new AppenderControlArraySet();
71      private final String name;
72      private LogEventFactory logEventFactory;
73      private Level level;
74      private boolean additive = true;
75      private boolean includeLocation = true;
76      private LoggerConfig parent;
77      private Map<Property, Boolean> propertiesMap;
78      private final List<Property> properties;
79      private final boolean propertiesRequireLookup;
80      private final Configuration config;
81      private final ReliabilityStrategy reliabilityStrategy;
82  
83      static {
84          final String factory = PropertiesUtil.getProperties().getStringProperty(Constants.LOG4J_LOG_EVENT_FACTORY);
85          if (factory != null) {
86              try {
87                  final Class<?> clazz = Loader.loadClass(factory);
88                  if (clazz != null && LogEventFactory.class.isAssignableFrom(clazz)) {
89                      LOG_EVENT_FACTORY = (LogEventFactory) clazz.newInstance();
90                  }
91              } catch (final Exception ex) {
92                  LOGGER.error("Unable to create LogEventFactory {}", factory, ex);
93              }
94          }
95          if (LOG_EVENT_FACTORY == null) {
96              LOG_EVENT_FACTORY = Constants.ENABLE_THREADLOCALS
97                      ? new ReusableLogEventFactory()
98                      : new DefaultLogEventFactory();
99          }
100     }
101 
102     /**
103      * Default constructor.
104      */
105     public LoggerConfig() {
106         this.logEventFactory = LOG_EVENT_FACTORY;
107         this.level = Level.ERROR;
108         this.name = Strings.EMPTY;
109         this.properties = null;
110         this.propertiesRequireLookup = false;
111         this.config = null;
112         this.reliabilityStrategy = new DefaultReliabilityStrategy(this);
113     }
114 
115     /**
116      * Constructor that sets the name, level and additive values.
117      *
118      * @param name The Logger name.
119      * @param level The Level.
120      * @param additive true if the Logger is additive, false otherwise.
121      */
122     public LoggerConfig(final String name, final Level level, final boolean additive) {
123         this.logEventFactory = LOG_EVENT_FACTORY;
124         this.name = name;
125         this.level = level;
126         this.additive = additive;
127         this.properties = null;
128         this.propertiesRequireLookup = false;
129         this.config = null;
130         this.reliabilityStrategy = new DefaultReliabilityStrategy(this);
131     }
132 
133     protected LoggerConfig(final String name, final List<AppenderRef> appenders, final Filter filter,
134             final Level level, final boolean additive, final Property[] properties, final Configuration config,
135             final boolean includeLocation) {
136         super(filter);
137         this.logEventFactory = LOG_EVENT_FACTORY;
138         this.name = name;
139         this.appenderRefs = appenders;
140         this.level = level;
141         this.additive = additive;
142         this.includeLocation = includeLocation;
143         this.config = config;
144         if (properties != null && properties.length > 0) {
145             this.properties = Collections.unmodifiableList(Arrays.asList(Arrays.copyOf(
146                     properties, properties.length)));
147         } else {
148             this.properties = null;
149         }
150         this.propertiesRequireLookup = containsPropertyRequiringLookup(properties);
151         this.reliabilityStrategy = config.getReliabilityStrategy(this);
152     }
153 
154     private static boolean containsPropertyRequiringLookup(final Property[] properties) {
155         if (properties == null) {
156             return false;
157         }
158         for (int i = 0; i < properties.length; i++) {
159             if (properties[i].isValueNeedsLookup()) {
160                 return true;
161             }
162         }
163         return false;
164     }
165 
166     @Override
167     public Filter getFilter() {
168         return super.getFilter();
169     }
170 
171     /**
172      * Returns the name of the LoggerConfig.
173      *
174      * @return the name of the LoggerConfig.
175      */
176     public String getName() {
177         return name;
178     }
179 
180     /**
181      * Sets the parent of this LoggerConfig.
182      *
183      * @param parent the parent LoggerConfig.
184      */
185     public void setParent(final LoggerConfig parent) {
186         this.parent = parent;
187     }
188 
189     /**
190      * Returns the parent of this LoggerConfig.
191      *
192      * @return the LoggerConfig that is the parent of this one.
193      */
194     public LoggerConfig getParent() {
195         return this.parent;
196     }
197 
198     /**
199      * Adds an Appender to the LoggerConfig.
200      *
201      * @param appender The Appender to add.
202      * @param level The Level to use.
203      * @param filter A Filter for the Appender reference.
204      */
205     public void addAppender(final Appender appender, final Level level, final Filter filter) {
206         appenders.add(new AppenderControl(appender, level, filter));
207     }
208 
209     /**
210      * Removes the Appender with the specific name.
211      *
212      * @param name The name of the Appender.
213      */
214     public void removeAppender(final String name) {
215         AppenderControl removed = null;
216         while ((removed = appenders.remove(name)) != null) {
217             cleanupFilter(removed);
218         }
219     }
220 
221     /**
222      * Returns all Appenders as a Map.
223      *
224      * @return a Map with the Appender name as the key and the Appender as the value.
225      */
226     public Map<String, Appender> getAppenders() {
227         return appenders.asMap();
228     }
229 
230     /**
231      * Removes all Appenders.
232      */
233     protected void clearAppenders() {
234         do {
235             final AppenderControl[] original = appenders.clear();
236             for (final AppenderControl ctl : original) {
237                 cleanupFilter(ctl);
238             }
239         } while (!appenders.isEmpty());
240     }
241 
242     private void cleanupFilter(final AppenderControl ctl) {
243         final Filter filter = ctl.getFilter();
244         if (filter != null) {
245             ctl.removeFilter(filter);
246             filter.stop();
247         }
248     }
249 
250     /**
251      * Returns the Appender references.
252      *
253      * @return a List of all the Appender names attached to this LoggerConfig.
254      */
255     public List<AppenderRef> getAppenderRefs() {
256         return appenderRefs;
257     }
258 
259     /**
260      * Sets the logging Level.
261      *
262      * @param level The logging Level.
263      */
264     public void setLevel(final Level level) {
265         this.level = level;
266     }
267 
268     /**
269      * Returns the logging Level.
270      *
271      * @return the logging Level.
272      */
273     public Level getLevel() {
274         return level == null ? parent == null ? Level.ERROR : parent.getLevel() : level;
275     }
276 
277     /**
278      * Returns the LogEventFactory.
279      *
280      * @return the LogEventFactory.
281      */
282     public LogEventFactory getLogEventFactory() {
283         return logEventFactory;
284     }
285 
286     /**
287      * Sets the LogEventFactory. Usually the LogEventFactory will be this LoggerConfig.
288      *
289      * @param logEventFactory the LogEventFactory.
290      */
291     public void setLogEventFactory(final LogEventFactory logEventFactory) {
292         this.logEventFactory = logEventFactory;
293     }
294 
295     /**
296      * Returns the valid of the additive flag.
297      *
298      * @return true if the LoggerConfig is additive, false otherwise.
299      */
300     public boolean isAdditive() {
301         return additive;
302     }
303 
304     /**
305      * Sets the additive setting.
306      *
307      * @param additive true if the LoggerConfig should be additive, false otherwise.
308      */
309     public void setAdditive(final boolean additive) {
310         this.additive = additive;
311     }
312 
313     /**
314      * Returns the value of logger configuration attribute {@code includeLocation}, or, if no such attribute was
315      * configured, {@code true} if logging is synchronous or {@code false} if logging is asynchronous.
316      *
317      * @return whether location should be passed downstream
318      */
319     public boolean isIncludeLocation() {
320         return includeLocation;
321     }
322 
323     /**
324      * Returns an unmodifiable map with the configuration properties, or {@code null} if this {@code LoggerConfig} does
325      * not have any configuration properties.
326      * <p>
327      * For each {@code Property} key in the map, the value is {@code true} if the property value has a variable that
328      * needs to be substituted.
329      *
330      * @return an unmodifiable map with the configuration properties, or {@code null}
331      * @see Configuration#getStrSubstitutor()
332      * @see StrSubstitutor
333      * @deprecated use {@link #getPropertyList()} instead
334      */
335     // LOG4J2-157
336     @Deprecated
337     public Map<Property, Boolean> getProperties() {
338         if (properties == null) {
339             return null;
340         }
341         if (propertiesMap == null) { // lazily initialize: only used by user custom code, not by Log4j any more
342             final Map<Property, Boolean> result = new HashMap<>(properties.size() * 2);
343             for (int i = 0; i < properties.size(); i++) {
344                 result.put(properties.get(i), Boolean.valueOf(properties.get(i).isValueNeedsLookup()));
345             }
346             propertiesMap = Collections.unmodifiableMap(result);
347         }
348         return propertiesMap;
349     }
350 
351     /**
352      * Returns an unmodifiable list with the configuration properties, or {@code null} if this {@code LoggerConfig} does
353      * not have any configuration properties.
354      * <p>
355      * Each {@code Property} in the list has an attribute {@link Property#isValueNeedsLookup() valueNeedsLookup} that
356      * is {@code true} if the property value has a variable that needs to be substituted.
357      *
358      * @return an unmodifiable list with the configuration properties, or {@code null}
359      * @see Configuration#getStrSubstitutor()
360      * @see StrSubstitutor
361      * @since 2.7
362      */
363     public List<Property> getPropertyList() {
364         return properties;
365     }
366 
367     public boolean isPropertiesRequireLookup() {
368         return propertiesRequireLookup;
369     }
370 
371     /**
372      * Logs an event.
373      *
374      * @param loggerName The name of the Logger.
375      * @param fqcn The fully qualified class name of the caller.
376      * @param marker A Marker or null if none is present.
377      * @param level The event Level.
378      * @param data The Message.
379      * @param t A Throwable or null.
380      */
381     @PerformanceSensitive("allocation")
382     public void log(final String loggerName, final String fqcn, final Marker marker, final Level level,
383             final Message data, final Throwable t) {
384         List<Property> props = null;
385         if (!propertiesRequireLookup) {
386             props = properties;
387         } else {
388             if (properties != null) {
389                 props = new ArrayList<>(properties.size());
390                 final LogEvent event = Log4jLogEvent.newBuilder()
391                         .setMessage(data)
392                         .setMarker(marker)
393                         .setLevel(level)
394                         .setLoggerName(loggerName)
395                         .setLoggerFqcn(fqcn)
396                         .setThrown(t)
397                         .build();
398                 for (int i = 0; i < properties.size(); i++) {
399                     final Property prop = properties.get(i);
400                     final String value = prop.isValueNeedsLookup() // since LOG4J2-1575
401                             ? config.getStrSubstitutor().replace(event, prop.getValue()) //
402                             : prop.getValue();
403                     props.add(Property.createProperty(prop.getName(), value));
404                 }
405             }
406         }
407         final LogEvent logEvent = logEventFactory instanceof LocationAwareLogEventFactory ?
408             ((LocationAwareLogEventFactory) logEventFactory).createEvent(loggerName, marker, fqcn, requiresLocation() ?
409                 StackLocatorUtil.calcLocation(fqcn) : null, level, data, props, t) :
410             logEventFactory.createEvent(loggerName, marker, fqcn, level, data, props, t);
411         try {
412             log(logEvent, LoggerConfigPredicate.ALL);
413         } finally {
414             // LOG4J2-1583 prevent scrambled logs when logging calls are nested (logging in toString())
415             ReusableLogEventFactory.release(logEvent);
416         }
417     }
418 
419     /**
420      * Logs an event.
421      *
422      * @param loggerName The name of the Logger.
423      * @param fqcn The fully qualified class name of the caller.
424      * @param location the location of the caller.
425      * @param marker A Marker or null if none is present.
426      * @param level The event Level.
427      * @param data The Message.
428      * @param t A Throwable or null.
429      */
430     @PerformanceSensitive("allocation")
431     public void log(final String loggerName, final String fqcn, final StackTraceElement location, final Marker marker,
432         final Level level, final Message data, final Throwable t) {
433         List<Property> props = null;
434         if (!propertiesRequireLookup) {
435             props = properties;
436         } else {
437             if (properties != null) {
438                 props = new ArrayList<>(properties.size());
439                 final LogEvent event = Log4jLogEvent.newBuilder()
440                     .setMessage(data)
441                     .setMarker(marker)
442                     .setLevel(level)
443                     .setLoggerName(loggerName)
444                     .setLoggerFqcn(fqcn)
445                     .setThrown(t)
446                     .build();
447                 for (int i = 0; i < properties.size(); i++) {
448                     final Property prop = properties.get(i);
449                     final String value = prop.isValueNeedsLookup() // since LOG4J2-1575
450                         ? config.getStrSubstitutor().replace(event, prop.getValue()) //
451                         : prop.getValue();
452                     props.add(Property.createProperty(prop.getName(), value));
453                 }
454             }
455         }
456         final LogEvent logEvent = logEventFactory instanceof LocationAwareLogEventFactory ?
457             ((LocationAwareLogEventFactory) logEventFactory).createEvent(loggerName, marker, fqcn, location, level,
458                 data, props, t) : logEventFactory.createEvent(loggerName, marker, fqcn, level, data, props, t);
459         try {
460             log(logEvent, LoggerConfigPredicate.ALL);
461         } finally {
462             // LOG4J2-1583 prevent scrambled logs when logging calls are nested (logging in toString())
463             ReusableLogEventFactory.release(logEvent);
464         }
465     }
466 
467     /**
468      * Logs an event.
469      *
470      * @param event The log event.
471      */
472     public void log(final LogEvent event) {
473         log(event, LoggerConfigPredicate.ALL);
474     }
475 
476     /**
477      * Logs an event.
478      *
479      * @param event The log event.
480      * @param predicate predicate for which LoggerConfig instances to append to.
481      *                  A null value is equivalent to a true predicate.
482      */
483     protected void log(final LogEvent event, final LoggerConfigPredicate predicate) {
484         if (!isFiltered(event)) {
485             processLogEvent(event, predicate);
486         }
487     }
488 
489     /**
490      * Returns the object responsible for ensuring log events are delivered to a working appender, even during or after
491      * a reconfiguration.
492      *
493      * @return the object responsible for delivery of log events to the appender
494      */
495     public ReliabilityStrategy getReliabilityStrategy() {
496         return reliabilityStrategy;
497     }
498 
499     private void processLogEvent(final LogEvent event, final LoggerConfigPredicate predicate) {
500         event.setIncludeLocation(isIncludeLocation());
501         if (predicate.allow(this)) {
502             callAppenders(event);
503         }
504         logParent(event, predicate);
505     }
506 
507     public boolean requiresLocation() {
508         if (!includeLocation) {
509             return false;
510         }
511         AppenderControl[] controls = appenders.get();
512         LoggerConfig loggerConfig = this;
513         while (loggerConfig != null) {
514             for (AppenderControl control : controls) {
515                 Appender appender = control.getAppender();
516                 if (appender instanceof LocationAware && ((LocationAware) appender).requiresLocation()) {
517                     return true;
518                 }
519             }
520             if (loggerConfig.additive) {
521                 loggerConfig = loggerConfig.parent;
522                 if (loggerConfig != null) {
523                     controls = loggerConfig.appenders.get();
524                 }
525             } else {
526                 break;
527             }
528         }
529         return false;
530     }
531 
532     private void logParent(final LogEvent event, final LoggerConfigPredicate predicate) {
533         if (additive && parent != null) {
534             parent.log(event, predicate);
535         }
536     }
537 
538     @PerformanceSensitive("allocation")
539     protected void callAppenders(final LogEvent event) {
540         final AppenderControl[] controls = appenders.get();
541         //noinspection ForLoopReplaceableByForEach
542         for (int i = 0; i < controls.length; i++) {
543             controls[i].callAppender(event);
544         }
545     }
546 
547     @Override
548     public String toString() {
549         return Strings.isEmpty(name) ? ROOT : name;
550     }
551 
552     /**
553      * Factory method to create a LoggerConfig.
554      *
555      * @param additivity True if additive, false otherwise.
556      * @param level The Level to be associated with the Logger.
557      * @param loggerName The name of the Logger.
558      * @param includeLocation whether location should be passed downstream
559      * @param refs An array of Appender names.
560      * @param properties Properties to pass to the Logger.
561      * @param config The Configuration.
562      * @param filter A Filter.
563      * @return A new LoggerConfig.
564      * @deprecated Deprecated in 2.7; use {@link #createLogger(boolean, Level, String, String, AppenderRef[], Property[], Configuration, Filter)}
565      */
566     @Deprecated
567     public static LoggerConfig createLogger(final String additivity,
568             // @formatter:off
569             final Level level,
570             @PluginAttribute("name") final String loggerName,
571             final String includeLocation,
572             final AppenderRef[] refs,
573             final Property[] properties,
574             @PluginConfiguration final Configuration config,
575             final Filter filter) {
576             // @formatter:on
577         if (loggerName == null) {
578             LOGGER.error("Loggers cannot be configured without a name");
579             return null;
580         }
581 
582         final List<AppenderRef> appenderRefs = Arrays.asList(refs);
583         final String name = loggerName.equals(ROOT) ? Strings.EMPTY : loggerName;
584         final boolean additive = Booleans.parseBoolean(additivity, true);
585 
586         return new LoggerConfig(name, appenderRefs, filter, level, additive, properties, config,
587                 includeLocation(includeLocation, config));
588     }
589 
590     /**
591      * Factory method to create a LoggerConfig.
592      *
593      * @param additivity true if additive, false otherwise.
594      * @param level The Level to be associated with the Logger.
595      * @param loggerName The name of the Logger.
596      * @param includeLocation whether location should be passed downstream
597      * @param refs An array of Appender names.
598      * @param properties Properties to pass to the Logger.
599      * @param config The Configuration.
600      * @param filter A Filter.
601      * @return A new LoggerConfig.
602      * @since 2.6
603      */
604     @PluginFactory
605     public static LoggerConfig createLogger(
606          // @formatter:off
607         @PluginAttribute(value = "additivity", defaultBoolean = true) final boolean additivity,
608         @PluginAttribute("level") final Level level,
609         @Required(message = "Loggers cannot be configured without a name") @PluginAttribute("name") final String loggerName,
610         @PluginAttribute("includeLocation") final String includeLocation,
611         @PluginElement("AppenderRef") final AppenderRef[] refs,
612         @PluginElement("Properties") final Property[] properties,
613         @PluginConfiguration final Configuration config,
614         @PluginElement("Filter") final Filter filter
615         // @formatter:on
616     ) {
617         final String name = loggerName.equals(ROOT) ? Strings.EMPTY : loggerName;
618         return new LoggerConfig(name, Arrays.asList(refs), filter, level, additivity, properties, config,
619             includeLocation(includeLocation, config));
620     }
621 
622     /**
623      * @deprecated Please use {@link #includeLocation(String, Configuration)}
624      */
625     @Deprecated
626     protected static boolean includeLocation(final String includeLocationConfigValue) {
627         return includeLocation(includeLocationConfigValue, null);
628     }
629 
630     // Note: for asynchronous loggers, includeLocation default is FALSE,
631     // for synchronous loggers, includeLocation default is TRUE.
632     protected static boolean includeLocation(final String includeLocationConfigValue, final Configuration configuration) {
633         if (includeLocationConfigValue == null) {
634             LoggerContext context = null;
635             if (configuration != null) {
636                 context = configuration.getLoggerContext();
637             }
638             if (context != null) {
639                 return !(context instanceof AsyncLoggerContext);
640             } else {
641                 return !AsyncLoggerContextSelector.isSelected();
642             }
643         }
644         return Boolean.parseBoolean(includeLocationConfigValue);
645     }
646 
647     protected final boolean hasAppenders() {
648         return !appenders.isEmpty();
649     }
650 
651     /**
652      * The root Logger.
653      */
654     @Plugin(name = ROOT, category = Core.CATEGORY_NAME, printObject = true)
655     public static class RootLogger extends LoggerConfig {
656 
657         @PluginFactory
658         public static LoggerConfig createLogger(
659                 // @formatter:off
660                 @PluginAttribute("additivity") final String additivity,
661                 @PluginAttribute("level") final Level level,
662                 @PluginAttribute("includeLocation") final String includeLocation,
663                 @PluginElement("AppenderRef") final AppenderRef[] refs,
664                 @PluginElement("Properties") final Property[] properties,
665                 @PluginConfiguration final Configuration config,
666                 @PluginElement("Filter") final Filter filter) {
667                 // @formatter:on
668             final List<AppenderRef> appenderRefs = Arrays.asList(refs);
669             final Level actualLevel = level == null ? Level.ERROR : level;
670             final boolean additive = Booleans.parseBoolean(additivity, true);
671 
672             return new LoggerConfig(LogManager.ROOT_LOGGER_NAME, appenderRefs, filter, actualLevel, additive,
673                     properties, config, includeLocation(includeLocation, config));
674         }
675     }
676 
677     protected enum LoggerConfigPredicate {
678         ALL() {
679             @Override
680             boolean allow(final LoggerConfig config) {
681                 return true;
682             }
683         },
684         ASYNCHRONOUS_ONLY() {
685             @Override
686             boolean allow(final LoggerConfig config) {
687                 return config instanceof AsyncLoggerConfig;
688             }
689         },
690         SYNCHRONOUS_ONLY() {
691             @Override
692             boolean allow(final LoggerConfig config) {
693                 return !ASYNCHRONOUS_ONLY.allow(config);
694             }
695         };
696 
697         abstract boolean allow(LoggerConfig config);
698     }
699 }