Java : Entity (XML) with Examples

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

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

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

final var path = Path.of("R:", "java-work", "xxx");
System.out.println(path); // R:\java-work\xxx

Files.writeString(path, "yyy");

final var xml = """
        <!DOCTYPE root [
            <!ENTITY aaa "bbb">
            <!ENTITY xxx SYSTEM "file:///R:/java-work/xxx">
        ]>
        <root>
          &aaa;
          &xxx;
        </root>
        """;

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

//<root>
//  bbb
//  yyy
//</root>
printDocument(document);

final var entities = document.getDoctype().getEntities();

if (entities.getNamedItem("aaa") instanceof Entity entity) {
    System.out.println(entity); // [aaa: null]
    System.out.println(entity.getSystemId()); // null
}

if (entities.getNamedItem("xxx") instanceof Entity entity) {
    System.out.println(entity); // [xxx: null]
    System.out.println(entity.getSystemId()); // file:///R:/java-work/xxx
}

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.

• Java API Examples : Node

String getInputEncoding ()

An attribute specifying the encoding used for this entity at the time of parsing, when it is an external parsed entity.

final var path = Path.of("R:", "java-work", "xxx");
System.out.println(path); // R:\java-work\xxx

Files.writeString(path, "yyy");

final var xml = """
        <!DOCTYPE root [
            <!ENTITY aaa "bbb">
            <!ENTITY xxx SYSTEM "file:///R:/java-work/xxx">
        ]>
        <root>
          &aaa;
          &xxx;
        </root>
        """;

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

//<root>
//  bbb
//  yyy
//</root>
printDocument(document);

final var entities = document.getDoctype().getEntities();

if (entities.getNamedItem("aaa") instanceof Entity entity) {
    System.out.println(entity); // [aaa: null]
    System.out.println(entity.getInputEncoding()); // null
    System.out.println(entity.getSystemId()); // null
}

if (entities.getNamedItem("xxx") instanceof Entity entity) {
    System.out.println(entity); // [xxx: null]
    System.out.println(entity.getInputEncoding()); // UTF-8
    System.out.println(entity.getSystemId()); // file:///R:/java-work/xxx
}

String getNotationName ()

For unparsed entities, the name of the notation for the entity.

final var xml = """
        <!DOCTYPE root [
            <!ENTITY aaa SYSTEM "bbb" NDATA ccc>
        ]>
        <root/>
        """;

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

final var entities = document.getDoctype().getEntities();

if (entities.getNamedItem("aaa") instanceof Entity entity) {
    System.out.println(entity); // [aaa: null]
    System.out.println(entity.getSystemId()); // bbb
    System.out.println(entity.getNotationName()); // ccc
}

String getPublicId ()

The public identifier associated with the entity if specified, and null otherwise.

final var xml = """
        <!DOCTYPE root [
            <!ENTITY aaa PUBLIC "bbb" "ccc">
        ]>
        <root/>
        """;

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

final var entities = document.getDoctype().getEntities();

if (entities.getNamedItem("aaa") instanceof Entity entity) {
    System.out.println(entity); // [aaa: null]
    System.out.println(entity.getPublicId()); // bbb
    System.out.println(entity.getSystemId()); // ccc
}

String getSystemId ()

The system identifier associated with the entity if specified, and null otherwise.

Please see getInputEncoding().

String getXmlEncoding ()

An attribute specifying, as part of the text declaration, the encoding of this entity, when it is an external parsed entity.

final var path = Path.of("R:", "java-work", "xxx");
System.out.println(path); // R:\java-work\xxx

Files.writeString(path, """
        <?xml version="1.0" encoding="UTF-8"?>\
        yyy\
        """);

final var xml = """
        <!DOCTYPE root [
            <!ENTITY aaa "bbb">
            <!ENTITY xxx SYSTEM "file:///R:/java-work/xxx">
        ]>
        <root>
          &aaa;
          &xxx;
        </root>
        """;

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

//<root>
//  bbb
//  yyy
//</root>
printDocument(document);

final var entities = document.getDoctype().getEntities();

if (entities.getNamedItem("aaa") instanceof Entity entity) {
    System.out.println(entity); // [aaa: null]
    System.out.println(entity.getSystemId()); // null
    System.out.println(entity.getXmlVersion()); // null
    System.out.println(entity.getXmlEncoding()); // null
}

if (entities.getNamedItem("xxx") instanceof Entity entity) {
    System.out.println(entity); // [xxx: null]
    System.out.println(entity.getSystemId()); // file:///R:/java-work/xxx
    System.out.println(entity.getXmlVersion()); // 1.0
    System.out.println(entity.getXmlEncoding()); // UTF-8
}

final var path = Path.of("R:", "java-work", "aaa");
System.out.println(path); // R:\java-work\aaa

Files.writeString(path, """
        <?xml version="1.1" encoding="UTF-16"?>\
        bbb\
        """, StandardCharsets.UTF_16);

final var xml = """
        <?xml version="1.1" encoding="UTF-8"?>
        <!DOCTYPE root [
            <!ENTITY aaa SYSTEM "file:///R:/java-work/aaa">
        ]>
        <root>
          &aaa;
        </root>
        """;

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

//<root>
//  bbb
//</root>
printDocument(document);

final var entities = document.getDoctype().getEntities();

if (entities.getNamedItem("aaa") instanceof Entity entity) {
    System.out.println(entity); // [aaa: null]
    System.out.println(entity.getSystemId()); // file:///R:/java-work/aaa
    System.out.println(entity.getXmlVersion()); // 1.1
    System.out.println(entity.getXmlEncoding()); // UTF-16
}

String getXmlVersion ()

An attribute specifying, as part of the text declaration, the version number of this entity, when it is an external parsed entity.

Please see getXmlEncoding().

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.

• Java API Examples : Node