他是一個抽象類，你可以看看我寫的代碼：

public static void main(String[] args) {
?? ??? ?DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
?? ??? ?try {
?? ??? ??? ?DocumentBuilder db = dbf.newDocumentBuilder();
?? ??? ??? ?Document doc = db.parse("books.xml");
?? ??? ??? ?NodeList nlist = doc.getElementsByTagName("book");
?? ??? ??? ?for (int i = 0; i < nlist.getLength(); i++) {
?? ??? ??? ??? ?Node book = nlist.item(i);
?? ??? ??? ??? ?NamedNodeMap attrs = book.getAttributes();
?? ??? ??? ??? ?for (int j = 0; j < attrs.getLength(); j++) {
?? ??? ??? ??? ??? ?Node attr = attrs.item(j);
?? ??? ??? ??? ??? ?System.out.print("===>> 屬性名: " + attr.getNodeName());
?? ??? ??? ??? ??? ?System.out.println(", 屬性值: " + attr.getNodeValue()+" <<===");
?? ??? ??? ??? ?}

?? ??? ??? ??? ?NodeList childNodes = book.getChildNodes();
?? ??? ??? ??? ?for (int j = 0; j < childNodes.getLength(); j++) {
?? ??? ??? ??? ??? ?Node node = childNodes.item(j);
?? ??? ??? ??? ??? ?if (node.getNodeType() == Node.ELEMENT_NODE) {
?? ??? ??? ??? ??? ??? ?System.out.print("節點名: " + node.getNodeName());
?? ??? ??? ??? ??? ??? ?System.out.println(", 節點值: " + node.getTextContent());
?? ??? ??? ??? ??? ?}
?? ??? ??? ??? ?}
?? ??? ??? ?}
?? ??? ?} catch (Exception e) {
?? ??? ??? ?e.printStackTrace();
?? ??? ?}
?? ?}