Registry.pm

=head1 LICENSE

  Copyright (c) 1999-2009 The European Bioinformatics Institute and
  Genome Research Limited.  All rights reserved.

  This software is distributed under a modified Apache license.
  For license details, please see

    http://www.ensembl.org/info/about/code_licence.html

=head1 CONTACT

  Please email comments or questions to the public Ensembl
  developers list at <ensembl-dev@ebi.ac.uk>.

  Questions may also be sent to the Ensembl help desk at
  <helpdesk@ensembl.org>.

=cut

=head1 NAME

Bio::EnsEMBL::Registry

=head1 SYNOPSIS

  use Bio::EnsEMBL::Registry;

  my $registry = 'Bio::EnsEMBL::Registry';

  $registry->load_all("configuration_file");

  $gene_adaptor = $registry->get_adaptor( 'Human', 'Core', 'Gene' );


=head1 DESCRIPTION

All Adaptors are stored/registered using this module. This module should
then be used to get the adaptors needed.

The registry can be loaded from a configuration file using the load_all
method.

If a filename is passed to load_all then this is used.  Else if the
enviroment variable ENSEMBL_REGISTRY is set to the name on an existing
configuration file, then this is used.  Else if the file .ensembl_init
in your home directory exist, it is used.

For the Web server ENSEMBL_REGISTRY should be set in SiteDefs.pm.  This
will then be passed on to load_all.


The registry can also be loaded via the method load_registry_from_db
which given a database host will load the latest versions of the Ensembl
databases from it.

The four types of registries are for db adaptors, dba adaptors, dna
adaptors and the standard type.

=head2 db

These are registries for backwards compatibility and enable the
subroutines to add other adaptors to connections.

e.g. get_all_db_adaptors, get_db_adaptor, add_db_adaptor,
remove_db_adaptor are the old DBAdaptor subroutines which are now
redirected to the Registry.

So if before we had