        # File lib/em/streamer.rb, line 51
    51:     def initialize connection, filename, args = {}
    52:       @connection = connection
    53:       @http_chunks = args[:http_chunks]
    54:
    55:       if File.exist?(filename)
    56:         @size = File.size?(filename)
    57:         if @size <= MappingThreshold
    58:           stream_without_mapping filename
    59:         else
    60:           stream_with_mapping filename
    61:         end
    62:       else
    63:         fail "file not found"
    64:       end
    65:     end