@Override
        public void fromString(String string) throws TextParseException {
            if (string == null || string.isEmpty()) {
                throw new TextParseException("Integer value must be specified for port");
            }
            port = Integer.parseInt(string);
        }
Implements common functionality for SVCB and HTTPS records
src/main/java/core/org/xbill/DNS/SVCBBase.java