Cache::BaseCache -- abstract cache base class
BaseCache provides functionality common to all instances of a cache. It differs
from the CacheUtils package insofar as it is designed to be used as superclass
for cache implementations.
Cache::BaseCache is to be used as a superclass for cache implementations. The
most effective way to use BaseCache is to use the protected _set_backend
method, which will be used to retrieve the persistence mechanism. The subclass
can then inherit the BaseCache's implementation of get, set, etc. However, due
to the difficulty inheriting static methods in Perl, the subclass will likely
need to explicitly implement Clear, Purge, and Size. Also, a factory pattern
should be used to invoke the _complete_initialization routine after the object
is constructed.
package Cache::MyCache;
use vars qw( @ISA );
use Cache::BaseCache;
use Cache::MyBackend;
@ISA = qw( Cache::BaseCache );
sub new
{
my ( $self ) = _new( @_ );
$self->_complete_initialization( );
return $self;
}
sub _new
{
my ( $proto, $p_options_hash_ref ) = @_;
my $class = ref( $proto ) || $proto;
my $self = $class->SUPER::_new( $p_options_hash_ref );
$self->_set_backend( new Cache::MyBackend( ) );
return $self;
}
sub Clear
{
foreach my $namespace ( _Namespaces( ) )
{
_Get_Backend( )->delete_namespace( $namespace );
}
}
sub Purge
{
foreach my $namespace ( _Namespaces( ) )
{
_Get_Cache( $namespace )->purge( );
}
}
sub Size
{
my $size = 0;
foreach my $namespace ( _Namespaces( ) )
{
$size += _Get_Cache( $namespace )->size( );
}
return $size;
}
Cache::Cache, Cache::FileCache, Cache::MemoryCache
Original author: DeWitt Clinton <dewitt@unto.net>
Last author: $Author: dclinton $
Copyright (C) 2001-2003 DeWitt Clinton