de.fhg.igd.logging
Interface Logger

All Known Implementing Classes:

LoggerImpl, LoggerProxy

public interface Logger

This is the main logging interface.

It defines a set of convenience methods for logging at a specific LogLevel, for method entries and exits (either regular or by throwing an exception), as well as for caught exceptions.

Furthermore, usage at a specific log level may be checked at runtime by means of isEnabled(LogLevel).

Instances are available via LoggerFactory.getLogger() and LoggerFactory.getLogger(String).

Version:

"$Id: Logger.java 1913 2007-08-08 02:41:53Z jpeters $"

Author:

Matthias Pressfreund

Method Summary

void	caught(LogLevel level, String msg, Throwable thrown) This method implicitely calls log(de.fhg.igd.logging.LogLevel, java.lang.String) first, then caught(Throwable).
void	caught(Throwable thrown) This method is supposed to be used for logging the catching of a Throwable (and subclasses).
void	debug(String msg) Creates a log entry on LogLevel.DEBUG.
void	entering() This method is supposed to be used for logging the entry of a parameterless method.
void	entering(Object[] params) This method is supposed to be used for logging the entry of a method with a set of parameters.
void	error(String msg) Creates a log entry on LogLevel.ERROR.
void	exiting() This method is supposed to be used for logging the exit of a method without return value.
void	exiting(Object result) This method is supposed to be used for logging the exit of a method with a return value.
void	fatal(String msg) Creates a log entry on LogLevel.FATAL.
void	info(String msg) Creates a log entry on LogLevel.INFO.
boolean	isEnabled(LogLevel level) Find out if logging would be performed at the given log level.
void	log(LogLevel level, String msg) This is the generic log method to be used for creating a log entry on the specified log level.
void	severe(String msg) Creates a log entry on LogLevel.SEVERE.
void	throwing(LogLevel level, String msg, Throwable thrown) This method implicitely calls log(de.fhg.igd.logging.LogLevel, java.lang.String) first, then throwing(Throwable).
void	throwing(Throwable thrown) This method is supposed to be used for logging the creation and method exit by a Throwable (and subclasses).
void	trace(String msg) Creates a log entry on LogLevel.TRACE.
void	warning(String msg) Creates a log entry on LogLevel.WARNING.

Method Detail

log

void log(LogLevel level,
         String msg)

This is the generic log method to be used for creating a log entry on the specified log level.

Parameters:

level - The log level to be used for creating the log entry

msg - The message to be written into the log entry

trace

void trace(String msg)

Creates a log entry on LogLevel.TRACE.

Parameters:

msg - The message to be written into the log entry

debug

void debug(String msg)

Creates a log entry on LogLevel.DEBUG.

Parameters:

msg - The message to be written into the log entry

info

void info(String msg)

Creates a log entry on LogLevel.INFO.

Parameters:

msg - The message to be written into the log entry

warning

void warning(String msg)

Creates a log entry on LogLevel.WARNING.

Parameters:

msg - The message to be written into the log entry

error

void error(String msg)

Creates a log entry on LogLevel.ERROR.

Parameters:

msg - The message to be written into the log entry

severe

void severe(String msg)

Creates a log entry on LogLevel.SEVERE.

Parameters:

msg - The message to be written into the log entry

fatal

void fatal(String msg)

Creates a log entry on LogLevel.FATAL.

Parameters:

msg - The message to be written into the log entry

entering

void entering()

This method is supposed to be used for logging the entry of a parameterless method. Hereby, the used log level will be LogLevel.TRACE.

entering

void entering(Object[] params)

This method is supposed to be used for logging the entry of a method with a set of parameters. Hereby, the used log level will be LogLevel.TRACE.

Parameters:

params - The method parameters, for printing the toString() method will be called on each object

exiting

void exiting()

This method is supposed to be used for logging the exit of a method without return value. Hereby, the used log level will be LogLevel.TRACE.

exiting

void exiting(Object result)

This method is supposed to be used for logging the exit of a method with a return value. Hereby, the used log level will be LogLevel.TRACE.

Parameters:

result - The return value, for printing the toString() method will be called

throwing

void throwing(Throwable thrown)

This method is supposed to be used for logging the creation and method exit by a Throwable (and subclasses). Hereby, the used log level will be LogLevel.TRACE.

Parameters:

thrown - The exception that will be thrown

throwing

void throwing(LogLevel level,
              String msg,
              Throwable thrown)

This method implicitely calls log(de.fhg.igd.logging.LogLevel, java.lang.String) first, then throwing(Throwable).

Parameters:

level - The log level to be used for creating the log entry

msg - The message to be written into the log entry

thrown - The exception that will be thrown

caught

void caught(Throwable thrown)

This method is supposed to be used for logging the catching of a Throwable (and subclasses). Hereby, the used log level will be LogLevel.TRACE.

Parameters:

thrown - The exception that has been caught

caught

void caught(LogLevel level,
            String msg,
            Throwable thrown)

This method implicitely calls log(de.fhg.igd.logging.LogLevel, java.lang.String) first, then caught(Throwable).

Parameters:

level - The log level to be used for creating the log entry

msg - The message to be written into the log entry

thrown - The exception that has been caught

isEnabled

boolean isEnabled(LogLevel level)

Find out if logging would be performed at the given log level.

This method might be useful in cases of costly log message creation which should be performed only if really needed.

Parameters:

level - The log level to check for

Returns:

whether or not logging would be performed at the given log level