# File lib/openid/store/filesystem.rb, line 80
      def get_association(server_url, handle=nil)
        # the filename with empty handle is the prefix for the associations
        # for a given server url
        filename = get_association_filename(server_url, handle)
        if handle
          return _get_association(filename)
        end
        assoc_filenames = Dir.glob(filename.to_s + '*')

        assocs = assoc_filenames.collect do |f|
          _get_association(f)
        end

        assocs = assocs.find_all { |a| not a.nil? }
        assocs = assocs.sort_by { |a| a.issued }

        return nil if assocs.empty?
        return assocs[-1]
      end