class PDF::Reader::StandardKeyBuilder

def initialize(opts = {})
  @key_length    = opts[:key_length].to_i/8
  @revision      = opts[:revision].to_i
  @owner_key     = opts[:owner_key]
  @user_key      = opts[:user_key]
  @permissions   = opts[:permissions].to_i
  @encryptMeta   = opts.fetch(:encrypted_metadata, true)
  @file_id       = opts[:file_id] || ""
  if @key_length != 5 && @key_length != 16
    msg = "StandardKeyBuilder only supports 40 and 128 bit\
           encryption (#{@key_length * 8}bit)"
    raise UnsupportedFeatureError, msg
  end
end