NAME

Thread::Queue::Queueable - abstract class for marshalling elements for a Thread::Queue::Duplex queue

SYNOPSIS

use Thread::Queue::Queueable;
use base qw(Thread::Queue::Queueable);
#
#	implement onEnqueue method
#	(default implementation shown)
#
sub onEnqueue {
	my $obj = shift;
#
#	capture class name, and create shared
#	version of object
#
	return $obj->isa('ARRAY') ?
		(ref $obj, share([ @$obj ])) :
		(ref $obj, share({ %$obj }));
}
#
#	implement onDequeue method
#	(default implementation shown)
#
sub onDequeue {
	my ($class, $obj) = @_;
#
#	reconstruct as non-shared
#
	$obj = (ref $obj eq 'ARRAY') ? [ @$obj ] : { %$obj };
	bless $obj, $class;
	return $obj;
}
#
#	permit the object to be reconstructed on dequeueing
#
sub onCancel {
	my $obj = shift;
	return 1;
}
#
#	curse (ie, unbless) the object into a shared structure
#
sub curse {
	my $obj = shift;

	if ($obj->isa('HASH')) {
		my %cursed : shared = ();
		$cursed{$_} = $obj->{$_}
			foreach (keys %$obj);
		return \%cursed;
	}

	my @cursed : shared = ();
	$cursed[$_] = $obj->[$_]
		foreach (0..$#$obj);
	return \@cursed;
}
#
#	redeem (ie, rebless) the object into
#	the class
#
sub redeem {
	my ($class, $obj) = @_;

	if (ref $obj eq 'HASH') {
		my $redeemed = {};
		$redeemed->{$_} = $obj->{$_}
			foreach (keys %$obj);
		return bless $redeemed, $class;
	}

	my $redeemed = [];
	$redeemed->[$_] = $obj->[$_]
		foreach (0..$#$obj);
	return bless $redeemed, $class;
}

DESCRIPTION

Thread::Queue::Queueable (aka TQQ) provides abstract methods to be invoked whenever an object is enqueued or dequeued, in either the request or response direction, on a Thread::Queue::Duplex (TQD) queue.

The primary purpose is to simplify application logic so that marshalling/unmarhsalling of objects between threads is performed automatically. In addition, when subclassed, the application class can modify or add logic (e.g., notifying a server thread object to update its reference count when a wrapped object is passed between threads - see DBIx::Threaded for an example).

METHODS

Refer to the included classdocs for summary and detailed method descriptions.

SEE ALSO

Thread::Queue::Duplex, threads, threads::shared, Thread::Queue

AUTHOR, COPYRIGHT, & LICENSE

Dean Arnold, Presicient Corp. darnold@presicient.com

Copyright(C) 2005, Presicient Corp., USA

Permission is granted to use this software under the same terms as Perl itself. Refer to the Perl Artistic License for details.