# File lib/multi_json.rb, line 30
  def default_adapter
    return :oj if defined?(::Oj)
    return :yajl if defined?(::Yajl)
    return :json_gem if defined?(::JSON)
    return :gson if defined?(::Gson)

    REQUIREMENT_MAP.each do |(library, adapter)|
      begin
        require library
        return adapter
      rescue ::LoadError
        next
      end
    end

    Kernel.warn '[WARNING] MultiJson is using the default adapter (ok_json). We recommend loading a different JSON library to improve performance.'
    :ok_json
  end