code: protected void processAttribute(XMLObject samlObject, Attr attribute) throws UnmarshallingException {
  
      MetadataServiceList mdsl = (MetadataServiceList) samlObject;
  
      if (attribute.getLocalName().equals(MetadataServiceList.ID_ATTR_NAME)) {
        mdsl.setID(attribute.getValue());
        attribute.getOwnerElement().setIdAttributeNode(attribute, true);
      }
      else if (attribute.getLocalName().equals(MetadataServiceList.VERSION_ATTR_NAME)) {
        mdsl.setVersion(MetadataServiceListVersion.valueOf(attribute.getValue()));
      }
      else if (attribute.getLocalName().equals(MetadataServiceList.ISSUE_DATE_ATTR_NAME)
          && !Strings.isNullOrEmpty(attribute.getValue())) {
        mdsl.setIssueDate(new DateTime(attribute.getValue(), ISOChronology.getInstanceUTC()));
      }
      else if (attribute.getLocalName().equals(MetadataServiceList.NEXT_UPDATE_ATTR_NAME)
          && !Strings.isNullOrEmpty(attribute.getValue())) {
        mdsl.setNextUpdate(new DateTime(attribute.getValue(), ISOChronology.getInstanceUTC()));
      }
      else {
        super.processAttribute(samlObject, attribute);
      }
  
    }
docs: {@inheritDoc}