static String deserCustomOnly(byte[] nonNullValue)
        {
            try
            {
                // Same behaviour as deser(), but does NOT
                // fall back to old implementation.
                return readUTF(nonNullValue, 0, nonNullValue.length);
            }
            catch (UTFDataFormatException e)
            {
                throw new RuntimeException(e);
            }
        }
Deserialize using readUTF only.

@param nonNullValue
@return
protostuff-api/src/main/java/io/protostuff/StringSerializer.java