BaseCache(3)

NAME

       Cache::BaseCache -- abstract cache base class

DESCRIPTION

       BaseCache provides functionality common to all instances of a cache.
       It differes from the CacheUtils package insofar as it is designed to be
       used as superclass for cache implementations.

SYNOPSIS

       Cache::BaseCache is to be used as a superclass for cache implementa-
       tions.  The most effective way to use BaseCache is to use the protected
       _set_backend method, which will be used to retrieve the persistance
       mechanism.  The subclass can then inherit the BaseCache's implentation
       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 con-
       structed.

         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;
         }

SEE ALSO

       Cache::Cache, Cache::FileCache, Cache::MemoryCache

AUTHOR

       Original author: DeWitt Clinton <dewitt@unto.net>

       Last author:     $Author: dclinton $

       Copyright (C) 2001-2003 DeWitt Clinton

perl v5.8.6                       2003-04-15               Cache::BaseCache(3)