NAME

Class::Context - simple implementation of Context Object pattern

SYNOPSIS

Simple usage

    use Class::Context;
    my $context = Class::Context->new();

    $context->setExample('exampledata');
    print $context->getExample();
    # exampledata

    $context->setExample2({ some => 'hash'});
    print ref($context->getExample2());
    # HASH

strict usage

    my $context = Class::Context->new( strict => ['example']);

    $context->setExample('exampledata');
    print $context->getExample() . "\n";
    # exampledata

    $context->setExample2('die,hacker!');
    print ref($context->getExample2()) . "\n";
    # died with 'unknown param' message

basic method syntax

(get|set) + ucfirst(lc(paramname))

DESCRIPTION

This module does not generate methods on-the-fly and does not use "eval()", "no strict" or other dirty tricks.

EXTENDING

You can add more functionality by extending Class::Context.

Class::Context provides two basic operations - 'get' and 'set'. You can add or redefine it.

    package Mycontext;
    use strict;
    use base 'Class::Context';

    sub _defineCustomOperations
    {
        my $self = shift;

        # $self->{operations} is a hashref, where related functions stored
        # $self->{registry} is a hashref, where params stored

        # add new operation
        $self->{operations}->{load} = sub {
            my ($param) = @_;
            my $object = Some::Factory->create($param);
            $self->{registry}->{$param} = $object;
        };

        # redefine operation get.
        # add ondemand object loading
        $self->{operations}->{get} = sub {
            my ($param) = @_;
            if($self->{registry}->{$param}){
                return $self->{registry}->{$param};
            }else{
                $self->{operations}->{load}->($param);
                return $self->{registry}->{$param};
            }
            return 1;
        };

        # now if you invoke
        # $context->getRequest;
        # new object will be stored in $context->{registry}->{request}
        # or returned if it already exists

        return 1;
    }

Also you can redefine default exception method for more useful error handling sub _die { my $self = shift; my ($message) = @_;

        throw Error::Simple($message);    
    }

SEE ALSO

You can find a helpful information by using Google.

Keywords: 'Context Object Pattern', 'agile software development', 'software design patterns', 'Patterns of Enterprise Application Architecture'.

AUTHOR

cmapuk[0nline], cmapuk.0nline@gmail.com

COPYRIGHT AND LICENSE

Copyright (C) 2009 by cmapuk[0nline]

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.10.0 or, at your option, any later version of Perl 5 you may have available.