You can use something like the earlier mentionated Factory pattern. The User class always need to get data from somewhere, you can pass the datasource to it.

Untested code: 


# User doesn't mind if it is local or remote, he wants the data
package Lookup;
...
sub is_user_in_cache { ... }
sub get_user_data { warn 'You should implement this method!'; }
...
package Lookup::Remote;
use base 'Lookup';
sub get_user_data { ... }
...
package main;
use Lookup::Remote;
my $lookup = Lookup->new({ remote_uri => $uri, });

use User;
# Tell User class the lookup method it will use.
User->set_lookup($lookup);
my $user = User->new({ id => 1234, });

[download]
You will create interface methods for all Lookup objects. You can also create other Lookup classes, like Lookup::DBI, Lookup::CSV, etc, just implementing the interface methods. You can write a base class like Lookup, having all caching you need, and then specializing the datasources (DBI, CSV, SOAP).

I hope this helps.

In reply to Re: OO, Library Configuration and Class Variables by izut
in thread OO, Library Configuration and Class Variables by moot

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