XML DOM parser. Как получить дефолтное значение атрибута?

Есть xsd-схема students.xsd. Атрибут faculty имеет дефолтное значение mmf.

Есть xml-файл students.xml со списком студентов. У одного из студентов не указано название факультета.

Есть класс StudentsDomBuilder с методом buildStudent(). В этом методе устанавливаются значения полей объекта.

Как получить дефолтное значение атрибута faculty, чтобы засетать его объекту?

#students.xsd:

<?xml version="1.0" encoding="UTF-8"?>
<schema xmlns="http://www.w3.org/2001/XMLSchema"
        targetNamespace="http://www.example.com/students"
        xmlns:tns="http://www.example.com/students"
        elementFormDefault="qualified">
    <element name="students">
        <complexType>
            <sequence>
                <element name="student" type="tns:Student" minOccurs="1" maxOccurs="100"/>
            </sequence>
        </complexType>
    </element>

    <complexType name="Student">
        <sequence>
            <element name="name" type="string"/>
            <element name="telephone" type="positiveInteger"/>
            <element name="address" type="tns:Address"/>
        </sequence>
        <attribute name="login" type="tns:Login" use="required"/>
        <attribute name="faculty" use="optional" default="mmf">
            <simpleType>
                <restriction base="string">
                    <enumeration value="mmf"></enumeration>
                    <enumeration value="famcs"></enumeration>
                    <enumeration value="csan"></enumeration>
                </restriction>
            </simpleType>
        </attribute>
    </complexType>

    <simpleType name="Login">
        <restriction base="ID">
            <pattern value="([a-zA-z])[a-zA-z0-9]{7,19}"/>
        </restriction>
    </simpleType>
    <complexType name="Address">
        <sequence>
            <element name="country" type="string"/>
            <element name="city" type="string"/>
            <element name="street" type="string"/>
        </sequence>
    </complexType>
</schema>

#students.xml:

<?xml version="1.0" encoding="UTF-8" ?>
<students xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xmlns="http://www.example.com/students"
          xsi:schemaLocation="http://www.example.com/students students.xsd">

    <student login="MitarAlex7">
        <name>Mitar Alex</name>
        <telephone>2323551</telephone>
        <address>
            <country>Belarus</country>
            <city>Minsk</city>
            <street>Kalinouskaha</street>
        </address>
    </student>
    <student faculty="csan" login="Pashkin5" >
        <name>Pashkin Jan</name>
        <telephone>3453789</telephone>
        <address>
            <country>Belarus</country>
            <city>Polotsk</city>
            <street>Bahdanovicha</street>
        </address>
    </student>
</students>

#StudentsDomBuilder

public class StudentsDomBuilder {
    static Logger logger = LogManager.getLogger();
    private Set<Student> students;
    private DocumentBuilder docBuilder;

    public StudentsDomBuilder() {
        students = new HashSet<>();
        //configuration
        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
        try {
            docBuilder = factory.newDocumentBuilder();
        } catch (ParserConfigurationException e) {
            logger.error("Doc builder is not created.");
        }
    }

    public Set<Student> getStudents() {
        return students;
    }

    public void buildSetStudents(String filename) {
        Document doc;
        try {
            doc = docBuilder.parse(filename);
            Element root = doc.getDocumentElement();
            //getting a list of <student> child elements
            NodeList studentsList = root.getElementsByTagName("student");
            for (int i = 0; i < studentsList.getLength(); i++) {
                Element studentElement = (Element) studentsList.item(i);
                Student student = buildStudent(studentElement);
                students.add(student);
            }
        } catch (IOException | SAXException e) {
            logger.error("Students set is not built.");
        }
    }

    private Student buildStudent(Element studentElement) {
        Student student = new Student();
        if (studentElement.hasAttribute("faculty")) {
            student.setFaculty(studentElement.getAttribute("faculty"));
        } else {
            //TODO set default value
            student.setFaculty("mmf");
        }

        student.setName(getElementTextContent(studentElement, "name"));
        int tel = Integer.parseInt(getElementTextContent(studentElement, "telephone"));
        student.setTelephone(tel);
        Student.Address address = student.getAddress();
        //init an address object
        Element addressElement = (Element) studentElement.getElementsByTagName("address").item(0);
        address.setCountry(getElementTextContent(addressElement, "country"));
        address.setCity(getElementTextContent(addressElement, "city"));
        address.setStreet(getElementTextContent(addressElement, "street"));
        student.setLogin(studentElement.getAttribute("login"));
        return student;
    }

    //get the text content of the tag
    private String getElementTextContent(Element element, String elementName) {
        NodeList nList = element.getElementsByTagName(elementName);
        Node node = nList.item(0);
        return node.getTextContent();
    }
}