Class LoggerAdapter

  • Direct Known Subclasses:
    Log4J2Logger, Log4JLogger, LogbackLogger

    public abstract class LoggerAdapter
    extends Logger
    An adapter that redirect all Java logging events to an other logging framework. This class redefines the severe, warning, info, config, fine, finer and finest methods as abstract ones. Subclasses should implement those methods in order to map Java logging levels to the backend logging framework.

    All log methods are overriden in order to redirect to one of the above-cited methods. Note that this is the opposite approach than the Java logging framework one, which implemented everything on top of Logger.log(LogRecord). This adapter is defined in terms of severefinest methods instead because external frameworks like Commons-logging don't work with LogRecord, and sometime provides nothing else than convenience methods equivalent to severefinest.

    Restrictions
    Because the configuration is expected to be fully controled by the external logging framework, every configuration methods inherited from Logger are disabled:

    Since LoggerAdapters do not hold any configuration by themself, it is not strictly necessary to add them to the log manager. The adapters can be created, garbage-collected and recreated again while preserving their behavior since their configuration is entirely contained in the external logging framework.

    Localization
    This logger is always created without resource bundles. Localizations must be performed through explicit calls to logrb or log(LogRecord) methods. This is sufficient for GeoTools needs, which performs all localizations through the latter. Note that these methods will be slower in this LoggerAdapter than the default Logger because this adapter localizes and formats records immediately instead of letting the Handler performs this work only if needed.

    Logging levels
    If a log record level is not one of the predefined ones, then this class maps to the first level below the specified one. For example if a log record has some level between FINE and FINER, then the finer method will be invoked. See isLoggable(java.util.logging.Level) for implementation tips taking advantage of this rule.

    Subclasses
    The abstract methods required for subclassing handle redirect message logging to target framework.

    Throwable: When adapting to a logging framework that supports logging of Throwables implement log(Level, String, Throwable) if you wish to support this functionality.

    Throwable: When adapting to a logging framework that supports logging of Throwables * implement log(Level, String, Throwable) if you wish to support this functionality.

    Since:
    2.4
    Author:
    Martin Desruisseaux
    See Also:
    Logging
    • Constructor Detail

      • LoggerAdapter

        protected LoggerAdapter​(String name)
        Creates a new logger.
        Parameters:
        name - The logger name.
    • Method Detail

      • setLevel

        public abstract void setLevel​(Level level)
        Sets the level for this logger. Subclasses must redirect the call to the external logging framework, or do nothing if the level can not be changed programmatically.
        Overrides:
        setLevel in class Logger
      • getLevel

        public abstract Level getLevel()
        Returns the level for this logger. Subclasses shall get this level from the external logging framework.
        Overrides:
        getLevel in class Logger
      • isLoggable

        public abstract boolean isLoggable​(Level level)
        Returns true if the specified level is loggable.

        Implementation tip
        Given that Level.intValue() for all predefined levels are documented in the Level specification and are multiple of 100, given that integer divisions are rounded toward zero and given rule documented in this class javadoc, then logging levels can be efficiently mapped to predefined levels using switch statements as below. This statement has good chances to be compiled to the tableswitch bytecode rather than lookupswitch (see Compiling Switches in The Java Virtual Machine Specification).

        Overrides:
        isLoggable in class Logger
      • info

        public abstract void info​(String message)
        Logs an INFO message.
        Overrides:
        info in class Logger
      • fine

        public abstract void fine​(String message)
        Logs a FINE message.
        Overrides:
        fine in class Logger
      • finer

        public abstract void finer​(String message)
        Logs a FINER message.
        Overrides:
        finer in class Logger
      • entering

        public void entering​(String sourceClass,
                             String sourceMethod)
        Logs a method entry to the debug level. Compared to the default Logger, this implementation bypass the level check in order to let the backing logging framework do its own check.
        Overrides:
        entering in class Logger
      • entering

        public void entering​(String sourceClass,
                             String sourceMethod,
                             Object param)
        Logs a method entry to the debug level with one parameter. Compared to the default Logger, this implementation bypass the level check in order to let the backing logging framework do its own check.
        Overrides:
        entering in class Logger
      • entering

        public void entering​(String sourceClass,
                             String sourceMethod,
                             Object[] params)
        Logs a method entry to the debug level with many parameters. Compared to the default Logger, this implementation bypass the level check in order to let the backing logging framework do its own check.
        Overrides:
        entering in class Logger
      • exiting

        public void exiting​(String sourceClass,
                            String sourceMethod)
        Logs a method return to the debug level. Compared to the default Logger, this implementation bypass the level check in order to let the backing logging framework do its own check.
        Overrides:
        exiting in class Logger
      • exiting

        public void exiting​(String sourceClass,
                            String sourceMethod,
                            Object result)
        Logs a method return to the debug level. Compared to the default Logger, this implementation bypass the level check in order to let the backing logging framework do its own check.
        Overrides:
        exiting in class Logger
      • throwing

        public void throwing​(String sourceClass,
                             String sourceMethod,
                             Throwable thrown)
        Logs a method failure to the debug level. Compared to the default Logger, this implementation bypass the level check in order to let the backing logging framework do its own check.
        Overrides:
        throwing in class Logger
      • log

        public void log​(LogRecord record)
        Logs a record. The default implementation delegates to logrb.
        Overrides:
        log in class Logger
      • log

        public void log​(Level level,
                        String message,
                        Throwable thrown)
        Logs a record at the specified level. The default implementation discards the exception and delegates to log(level, message).
        Overrides:
        log in class Logger
      • log

        public void log​(Level level,
                        String message,
                        Object param)
        Logs a record at the specified level. The defaut implementation delegates to log(level, message, params) where the params array is built from the param object.
        Overrides:
        log in class Logger
      • log

        public void log​(Level level,
                        String message,
                        Object[] params)
        Logs a record at the specified level. The defaut implementation formats the message immediately, then delegates to log(level, message) .
        Overrides:
        log in class Logger
      • logp

        public void logp​(Level level,
                         String sourceClass,
                         String sourceMethod,
                         String message)
        Logs a record at the specified level. The defaut implementation discards the source class and source method, then delegates to log(level, message) .
        Overrides:
        logp in class Logger
      • logp

        public void logp​(Level level,
                         String sourceClass,
                         String sourceMethod,
                         String message,
                         Throwable thrown)
        Logs a record at the specified level. The defaut implementation discards the source class and source method, then delegates to log(level, message, thrown).
        Overrides:
        logp in class Logger
      • logp

        public void logp​(Level level,
                         String sourceClass,
                         String sourceMethod,
                         String message,
                         Object param)
        Logs a record at the specified level. The defaut implementation delegates to logp(level, sourceClass, sourceMethod, message, params) where the params array is built from the param object.

        Note that sourceClass and sourceMethod will be discarted unless the target logp method has been overriden.

        Overrides:
        logp in class Logger
      • logp

        public void logp​(Level level,
                         String sourceClass,
                         String sourceMethod,
                         String message,
                         Object[] params)
        Logs a record at the specified level. The defaut implementation formats the message immediately, then delegates to logp(level, sourceClass, sourceMethod, message).

        Note that sourceClass and sourceMethod will be discarted unless the target logp method has been overriden.

        Overrides:
        logp in class Logger
      • logrb

        public void logrb​(Level level,
                          String sourceClass,
                          String sourceMethod,
                          String bundleName,
                          String message)
        Logs a localizable record at the specified level. The defaut implementation localizes the message immediately, then delegates to logp(level, sourceClass, sourceMethod, message).
        Overrides:
        logrb in class Logger
      • logrb

        public void logrb​(Level level,
                          String sourceClass,
                          String sourceMethod,
                          String bundleName,
                          String message,
                          Throwable thrown)
        Logs a localizable record at the specified level. The defaut implementation localizes the message immediately, then delegates to logp(level, sourceClass, sourceMethod, message, thrown).
        Overrides:
        logrb in class Logger
      • logrb

        public void logrb​(Level level,
                          String sourceClass,
                          String sourceMethod,
                          String bundleName,
                          String message,
                          Object param)
        Logs a localizable record at the specified level. The defaut implementation localizes the message immediately, then delegates to logp(level, sourceClass, sourceMethod, message, param).
        Overrides:
        logrb in class Logger
      • logrb

        public void logrb​(Level level,
                          String sourceClass,
                          String sourceMethod,
                          String bundleName,
                          String message,
                          Object[] params)
        Logs a localizable record at the specified level. The defaut implementation localizes the message immediately, then delegates to logp(level, sourceClass, sourceMethod, message, params).
        Overrides:
        logrb in class Logger
      • addHandler

        public void addHandler​(Handler handler)
        Do nothing since this logger adapter does not supports handlers. The configuration should be fully controlled by the external logging framework (e.g. Commons-logging) instead, which is not expected to use Handler objects.
        Overrides:
        addHandler in class Logger
      • removeHandler

        public void removeHandler​(Handler handler)
        Do nothing since this logger adapter does not support handlers.
        Overrides:
        removeHandler in class Logger
      • setUseParentHandlers

        public void setUseParentHandlers​(boolean useParentHandlers)
        Do nothing since this logger never use parent handlers. This is consistent with addHandler(java.util.logging.Handler) not allowing to add any handlers, and avoid mixing loggings from the external framework with Java loggings.
        Overrides:
        setUseParentHandlers in class Logger
      • setParent

        public void setParent​(Logger parent)
        Do nothing since this logger adapter does not support arbitrary parents. More specifically, it should not inherits any configuration from a parent logger using the Java logging framework.
        Overrides:
        setParent in class Logger
      • setFilter

        public void setFilter​(Filter filter)
        Do nothing since this logger adapter does not support filters. It is difficult to query efficiently the filter in this LoggerAdapter architecture (e.g. we would need to make sure that Filter.isLoggable(java.util.logging.LogRecord) is invoked only once even if a log call is cascaded into many other log calls, and this test must works in multi-threads environment).
        Overrides:
        setFilter in class Logger