code: public static double getValueAsDouble(byte[] key,
        NavigableMap<byte[], byte[]> infoValues) {
      byte[] value = infoValues.get(key);
      if (value != null) {
        return Bytes.toDouble(value);
      } else {
        return 0.0;
      }
    }
docs: return a value from the NavigableMap as a Double
  @param key to be looked up for the value
  @param infoValues - the map containing the key values
  @return value as Double or 0.0