Java : Attr (XML) with Examples

public void printDocument(Document document) throws TransformerException {
    final var transformer = TransformerFactory.newInstance().newTransformer();
    transformer.setOutputProperty(OutputKeys.INDENT, "yes");
    transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");

    final var result = new StreamResult(new StringWriter());
    transformer.transform(new DOMSource(document), result);

    System.out.print(result.getWriter());
}

final var builder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
final var document = builder.newDocument();

final var root = document.createElement("root");
System.out.println(root); // [root: null]

document.appendChild(root);

final var child = document.createElement("child");
System.out.println(child); // [child: null]

root.appendChild(child);

final var attrA = document.createAttribute("aa");
attrA.setValue("AA");
System.out.println(attrA); // aa="AA"

child.setAttributeNode(attrA);

final var attrB = document.createAttribute("bb");
attrB.setValue("BB");
System.out.println(attrB); // bb="BB"

child.setAttributeNode(attrB);

//<root>
//    <child aa="AA" bb="BB"/>
//</root>
printDocument(document);

ATTRIBUTE_NODE, CDATA_SECTION_NODE, COMMENT_NODE, DOCUMENT_FRAGMENT_NODE, DOCUMENT_NODE, DOCUMENT_POSITION_CONTAINED_BY, DOCUMENT_POSITION_CONTAINS, DOCUMENT_POSITION_DISCONNECTED, DOCUMENT_POSITION_FOLLOWING, DOCUMENT_POSITION_IMPLEMENTATION_SPECIFIC, DOCUMENT_POSITION_PRECEDING, DOCUMENT_TYPE_NODE, ELEMENT_NODE, ENTITY_NODE, ENTITY_REFERENCE_NODE, NOTATION_NODE, PROCESSING_INSTRUCTION_NODE, TEXT_NODE

Please see the link below.

• Node with Examples

String getName ()

Returns the name of this attribute.

final var xml = """
        <root>
            <child aa="AA"/>
        </root>
        """;

final var builder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
final var document = builder.parse(new ByteArrayInputStream(xml.getBytes()));

final var child = document.getElementsByTagName("child").item(0);
if (child instanceof Element element) {
    final var attr = element.getAttributeNode("aa");
    System.out.println(attr); // aa="AA"

    System.out.println(attr.getName()); // aa
    System.out.println(attr.getValue()); // AA
    System.out.println(attr.getSchemaTypeInfo()); // aa="AA"
}

Element getOwnerElement ()

The Element node this attribute is attached to or null if this attribute is not in use.

final var xml = """
        <root>
            <child aa="AA"/>
        </root>
        """;

final var builder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
final var document = builder.parse(new ByteArrayInputStream(xml.getBytes()));

final var child = document.getElementsByTagName("child").item(0);
if (child instanceof Element element) {
    final var attr = element.getAttributeNode("aa");
    System.out.println(attr); // aa="AA"

    final var owner = attr.getOwnerElement();
    System.out.println(owner); // [child: null]
    System.out.println(owner.isSameNode(child)); // true
}

TypeInfo getSchemaTypeInfo ()

The type information associated with this attribute.

final var xml = """
        <root>
            <child aa="AA"/>
        </root>
        """;

final var builder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
final var document = builder.parse(new ByteArrayInputStream(xml.getBytes()));

final var child = document.getElementsByTagName("child").item(0);
if (child instanceof Element element) {
    final var attr = element.getAttributeNode("aa");
    System.out.println(attr); // aa="AA"

    System.out.println(attr.getName()); // aa
    System.out.println(attr.getValue()); // AA
    System.out.println(attr.getSchemaTypeInfo()); // aa="AA"
}

boolean getSpecified ()

True if this attribute was explicitly given a value in the instance document, false otherwise.

final var xml = """
        <!DOCTYPE root [
          <!ATTLIST child answer (yes|no) "no">
        ]>
        <root>
            <child a="A"/>
        </root>
        """;

final var builder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
final var document = builder.parse(new ByteArrayInputStream(xml.getBytes()));

final var child = document.getElementsByTagName("child").item(0);
if (child instanceof Element element) {
    System.out.println(element); // [child: null]

    final var attrAnswer = element.getAttributeNode("answer");
    System.out.println(attrAnswer); // answer="no"
    System.out.println(attrAnswer.getSpecified()); // false

    final var attrA = element.getAttributeNode("a");
    System.out.println(attrA); // a="A"
    System.out.println(attrA.getSpecified()); // true
}

String getValue ()

On retrieval, the value of the attribute is returned as a string.

final var xml = """
        <root>
            <child aa="AA"/>
        </root>
        """;

final var builder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
final var document = builder.parse(new ByteArrayInputStream(xml.getBytes()));

final var child = document.getElementsByTagName("child").item(0);
if (child instanceof Element element) {
    final var attr = element.getAttributeNode("aa");
    System.out.println(attr); // aa="AA"

    System.out.println(attr.getName()); // aa
    System.out.println(attr.getValue()); // AA
    System.out.println(attr.getSchemaTypeInfo()); // aa="AA"
}

boolean isId ()

Returns whether this attribute is known to be of type ID (i.e. to contain an identifier for its owner element) or not.

final var xml = """
        <!DOCTYPE root [
          <!ATTLIST child id-a ID "ID-A">
        ]>
        <root>
            <child id-a="ID-A" b="B"/>
        </root>
        """;

final var builder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
final var document = builder.parse(new ByteArrayInputStream(xml.getBytes()));

final var child = document.getElementById("ID-A");
System.out.println(child); // [child: null]

final var attrId = child.getAttributeNode("id-a");
System.out.println(attrId); // id-a="ID-A"
System.out.println(attrId.isId()); // true

final var attrB = child.getAttributeNode("b");
System.out.println(attrB); // b="B"
System.out.println(attrB.isId()); // false

void setValue (String value)

On retrieval, the value of the attribute is returned as a string.

final var xml = """
        <root><child aa="AA"/></root>
        """;

final var builder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
final var document = builder.parse(new ByteArrayInputStream(xml.getBytes()));

final var child = document.getElementsByTagName("child").item(0);
if (child instanceof Element element) {

    //<root>
    //    <child aa="AA"/>
    //</root>
    printDocument(document);

    final var attrA = element.getAttributeNode("aa");
    System.out.println(attrA); // aa="AA"

    attrA.setValue("XYZ");
    System.out.println(attrA); // aa="XYZ"

    //<root>
    //    <child aa="XYZ"/>
    //</root>
    printDocument(document);

    final var attrB = document.createAttribute("bb");
    attrB.setValue("BB");
    System.out.println(attrB); // bb="BB"

    element.setAttributeNode(attrB);

    //<root>
    //    <child aa="XYZ" bb="BB"/>
    //</root>
    printDocument(document);
}

appendChild, cloneNode, compareDocumentPosition, getAttributes, getBaseURI, getChildNodes, getFeature, getFirstChild, getLastChild, getLocalName, getNamespaceURI, getNextSibling, getNodeName, getNodeType, getNodeValue, getOwnerDocument, getParentNode, getPrefix, getPreviousSibling, getTextContent, getUserData, hasAttributes, hasChildNodes, insertBefore, isDefaultNamespace, isEqualNode, isSameNode, isSupported, lookupNamespaceURI, lookupPrefix, normalize, removeChild, replaceChild, setNodeValue, setPrefix, setTextContent, setUserData

Please see the link below.

• Node with Examples