A logger class. More...

#include <Logger.h>

Public Member Functions
	Logger (Logger &parent, const std::string &subdomain)
	Creates a logger. More...

	Logger (Logger &parent, const std::string &subdomain, LogLevel threshold)
	Creates a logger. More...

	~Logger ()
	Destroys a logger.

void	addDestination (LogDestination &destination)
	Adds a LogDestination. More...

void	addDestinations (const std::list< LogDestination * > &destinations)
	Adds LogDestinations. More...

void	setDestinations (const std::list< LogDestination * > &destinations)
	Set LogDestinations. More...

const std::list < LogDestination * > &	getDestinations (void) const
	Obtains current LogDestinations. More...

void	removeDestinations (void)
	Removes all LogDestinations.

void	deleteDestinations (void)
	Remove all LogDestinations and delete LogDestination objects.

void	setThreshold (LogLevel threshold)
	Sets the logging threshold. More...

LogLevel	getThreshold () const
	Returns the threshold of this logger.

void	setThreadContext (void)
	Creates per-thread context. More...

void	msg (LogMessage message)
	Sends a LogMessage. More...

void	msg (LogLevel level, const std::string &str)
	Logs a message text. More...

Static Public Member Functions
static Logger &	getRootLogger ()
	The root Logger. More...

static void	setThresholdForDomain (LogLevel threshold, const std::list< std::string > &subdomains)
	Sets the threshold for domain. More...

static void	setThresholdForDomain (LogLevel threshold, const std::string &domain)
	Sets the threshold for domain. More...

Detailed Description

A logger class.

This class defines a Logger to which LogMessages can be sent.

Every Logger (except for the rootLogger) has a parent Logger. The domain of a Logger (a string that indicates the origin of LogMessages) is composed by adding a subdomain to the domain of its parent Logger.

A Logger also has a threshold. Every LogMessage that have a level that is greater than or equal to the threshold is forwarded to any LogDestination connected to this Logger as well as to the parent Logger.

Typical usage of the Logger class is to declare a global Logger object for each library/module/component to be used by all classes and methods there.

Logger messages may be localised according to the current locale. Some locales are better supported than others.

Example code for setting up logger in main():

// Set up stderr as a log stream
Arc::LogStream logcerr(std::cerr);
// Log message is prefixed by level only
logcerr.setFormat(Arc::ShortFormat);
// Add the stderr destination to the root logger
Arc::Logger::getRootLogger().addDestination(logcerr);
// Set the logging threshold to WARNING
Arc::Logger::getRootLogger().setThreshold(Arc::WARNING);
// Logger to use in main() - it inherits all properties from the root Logger
Arc::Logger logger(Arc::Logger::getRootLogger(), "main");
// this message will not be logged since it is below the threshold
logger.msg(Arc::INFO, "main started");
int i = 5;
// This message will be logged
logger.msg(Arc::ERROR, "Oops, an error occurred when i was %i", i);

Constructor & Destructor Documentation

Arc::Logger::Logger	(	Logger &	parent,
		const std::string &	subdomain
	)

Creates a logger.

The threshold is inherited from its parent Logger.

Parameters

parent	The parent Logger of the new Logger.
subdomain	The subdomain of the new logger.

Arc::Logger::Logger	(	Logger &	parent,
		const std::string &	subdomain,
		LogLevel	threshold
	)

Creates a logger.

Parameters

parent	The parent Logger of the new Logger.
subdomain	The subdomain of the new logger.
threshold	The threshold of the new logger.

Member Function Documentation

void Arc::Logger::addDestination ( LogDestination & destination )

Adds a LogDestination.

Adds a LogDestination to which to forward LogMessages sent to this logger (if they pass the threshold). Since LogDestinations should not be copied, the new LogDestination is passed by reference and a pointer to it is kept for later use. It is therefore important that the LogDestination passed to this Logger exists at least as long as the Logger itself.

void Arc::Logger::addDestinations ( const std::list< LogDestination * > & destinations )

Adds LogDestinations.

See addDestination(LogDestination& destination).

const std::list<LogDestination*>& Arc::Logger::getDestinations ( void ) const

Obtains current LogDestinations.

Returns list of pointers to LogDestination objects. Returned result refers directly to internal member of Logger instance. Hence it should not be used after this Logger is destroyed.

static Logger& Arc::Logger::getRootLogger ( )

static

The root Logger.

This is the root Logger. It is an ancestor of any other Logger and always exists.

void Arc::Logger::msg ( LogMessage message )

Sends a LogMessage.

Parameters

message The LogMessage to send.

void Arc::Logger::msg	(	LogLevel	level,
		const std::string &	str
	)

inline

Logs a message text.

Logs a message text string at the specified LogLevel. This is a convenience method to save some typing. It simply creates a LogMessage and sends it to the other msg() methods. It is also possible to use msg() with multiple arguments and printf-style string formatting, for example

logger.msg(INFO, "Operation no %i failed: %s", number, reason);

Parameters

level	The level of the message.
str	The message text.

void Arc::Logger::setDestinations ( const std::list< LogDestination * > & destinations )

Set LogDestinations.

A safe atomic way to remove and add LogDestinations.

void Arc::Logger::setThreadContext ( void )

Creates per-thread context.

Creates new context for this logger which becomes effective for operations initiated by this thread. All new threads started by this one will inherit new context. Context stores current threshold and pointers to destinations. Hence new context is identical to current one. One can modify new context using setThreshold(), removeDestinations() and addDestination(). All such operations will not affect old context.

void Arc::Logger::setThreshold ( LogLevel threshold )

Sets the logging threshold.

This method sets the threshold of the Logger. Any message sent to this Logger that has a level below this threshold will be discarded.

Parameters

threshold The threshold

static void Arc::Logger::setThresholdForDomain	(	LogLevel	threshold,
		const std::list< std::string > &	subdomains
	)

static

Sets the threshold for domain.

This method sets the default threshold of the domain. All new loggers created with specified domain will have specified threshold set by default. The subdomains of all loggers in chain are matched against list of provided subdomains.

Parameters

threshold	The threshold
subdomains	The subdomains of all loggers in chain

static void Arc::Logger::setThresholdForDomain	(	LogLevel	threshold,
		const std::string &	domain
	)

static

Sets the threshold for domain.

This method sets the default threshold of the domain. All new loggers created with specified domain will have specified threshold set by default. The domain is composed of all subdomains of all loggers in chain by merging them with '.' as separator.

Parameters

threshold	The threshold
domain	The domain of logger

The documentation for this class was generated from the following file:

Logger.h

Public Member Functions

Static Public Member Functions

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation