trusty (3) Cache::BaseCache.3pm.gz

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 implementations.  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 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;
         }

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