/ 
Bio-NEXUS-0.72
River stage one • 1 direct dependent • 1 total dependent
/ Bio::NEXUS::Util::Logger

NAME

Bio::NEXUS::Util::Logger - Logging for Bio::NEXUS.

SYNOPSIS

use Bio::NEXUS::Util::Logger;

# can instantiate as (singleton) object, in this case telling it that only
# messages from Bio::NEXUS::Forest with log level >= 3 are displayed...
my $logger->new( -level => 3, -class => 'Bio::NEXUS::Matrix' );


#...or use static...
Bio::NEXUS::Util::Logger->info("Log level too low for this to be printed");
Bio::NEXUS::Matrix->VERBOSE( -level => 2 );
Bio::NEXUS::Util::Logger->info("Not any more, now we're talking");

DESCRIPTION

This class defines a logger, a utility object for logging messages. The other objects in Bio::NEXUS use this logger to give detailed feedback about what they are doing at per-class, user-configurable log levels (debug, info, warn, error and fatal). You can tell the logger for each class how verbose to be. The least verbose is level 0, in which case only 'fatal' messages are shown. The most verbose level, 4, shows debugging messages, include from internal methods (i.e. ones that start with underscores, and special 'ALLCAPS' perl methods like DESTROY or TIEARRAY). For example, to monitor what the root class is doing, you would say:

$logger->( -class => 'Bio::NEXUS', -level => 4 )

To define global verbosity you can omit the -class argument.

METHODS

CONSTRUCTOR

new()

Constructor for Logger.

Type    : Constructor
Title   : new
Usage   : my $logger = Bio::NEXUS::Util::Logger->new;
Function: Instantiates a logger
Returns : a Bio::NEXUS::Util::Logger object
Args    : -verbose => verbosity, 0 .. 4 (optional)
		   -package => a package for which to set verbosity (optional)

head2 LOGGING METHODS

log()

Prints argument debugging message, depending on verbosity.

Type    : logging method
Title   : log
Usage   : $logger->log( "WARN", "warning message" );
Function: prints logging message, depending on verbosity
Returns : invocant
Args    : message log level, logging message
debug()

Prints argument debugging message, depending on verbosity.

Type    : logging method
Title   : debug
Usage   : $logger->debug( "debugging message" );
Function: prints debugging message, depending on verbosity
Returns : invocant
Args    : logging message
info()

Prints argument informational message, depending on verbosity.

Type    : logging method
Title   : info
Usage   : $logger->info( "info message" );
Function: prints info message, depending on verbosity
Returns : invocant
Args    : logging message
warn()

Prints argument warning message, depending on verbosity.

Type    : logging method
Title   : warn
Usage   : $logger->warn( "warning message" );
Function: prints warning message, depending on verbosity
Returns : invocant
Args    : logging message
error()

Prints argument error message, depending on verbosity.

Type    : logging method
Title   : error
Usage   : $logger->error( "error message" );
Function: prints error message, depending on verbosity
Returns : invocant
Args    : logging message
fatal()

Prints argument fatal message, depending on verbosity.

Type    : logging method
Title   : fatal
Usage   : $logger->fatal( "fatal message" );
Function: prints fatal message, depending on verbosity
Returns : invocant
Args    : logging message
set_listeners()

Adds listeners to send log messages to.

Type    : Mutator
Title   : set_listeners()
Usage   : Bio::NEXUS::Util::Logger->set_listeners( sub { warn shift } )
Function: Sets additional listeners to log to (e.g. a file)
Returns : invocant
Args    : One or more code references
Comments: On execution of the listeners, the first (and only) argument 
          is the log message.
PREFIX()

Getter and setter of path prefix to strip from source file paths in messages.

Type    : Mutator/Accessor
Title   : PREFIX()
Usage   : Bio::NEXUS::Util::Logger->PREFIX( '/path/to/Bio/NEXUS' )
Function: Sets/gets $PREFIX
Returns : Verbose level
Args    : Optional: a path
Comments:
VERBOSE()

Setter for the verbose level. This comes in five levels: 0 = only fatal messages (though, when something fatal happens, you'll most likely get an exception object), 1 = errors (hopefully recoverable), 2 = warnings (recoverable), 3 = info (useful diagnostics), 4 = debug (almost every method call)

Type    : Mutator
Title   : VERBOSE()
Usage   : Bio::NEXUS::Util::Logger->VERBOSE( -level => $level )
Function: Sets/gets verbose level
Returns : Verbose level
Args    : 0 <= $level && $level <= 4
Comments:

REVISION

$Id: Logger.pm,v 1.2 2007/09/24 04:52:11 rvos Exp $