# File lib/marc/xml_parsers.rb, line 15
    def self.extended(receiver)
      # Start with a Nokogiri check
      begin
        require 'nokogiri'
        receiver.extend(NokogiriReader)
      rescue LoadError
        if RUBY_PLATFORM =~ /java/
          # If using JRuby, use JREXML if it's there
          begin
            receiver.extend(JREXMLReader)
            return
          rescue LoadError
          end
        end       
        # If you're here, you're stuck with lowly REXML
        receiver.extend(REXMLReader) 
      end        
    end