protected boolean checkMandatoryParams() {
        ParameterMandatory param = (ParameterMandatory) getSvcParamValue(MANDATORY);
        if (param != null) {
            for (int key : param.values) {
                if (getSvcParamValue(key) == null) {
                    return false;
                }
            }
        }
        return true;
    }
Implements common functionality for SVCB and HTTPS records
src/main/java/core/org/xbill/DNS/SVCBBase.java