Java操作Xml文件

import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.SAXException;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.*;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;

public class DomChap {
    public static void main(String[] args) throws ParserConfigurationException, TransformerException, IOException, SAXException {
        DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory.newInstance();
        DocumentBuilder documentBuilder = documentBuilderFactory.newDocumentBuilder();
        Document document = documentBuilder.newDocument();
        Element students = document.createElement("students");
        for (int i = 0; i < 10 ; i++) {
            Element student = document.createElement("student");
            student.setAttribute("id",Integer.toString(i));
            student.setAttribute("class","student");
            student.setTextContent("张"+i);
            students.appendChild(student);
        }
        document.appendChild(students);
        TransformerFactory transformerFactory = TransformerFactory.newInstance();
        Transformer transformer = transformerFactory.newTransformer();
        transformer.setOutputProperty(OutputKeys.INDENT, "yes");
        DOMSource domSource = new DOMSource(document);
        File file = new File("./students.xml");
        boolean newFile = file.createNewFile();
        FileOutputStream out = new FileOutputStream(file);
        StreamResult xmlResult = new StreamResult(out);
        transformer.transform(domSource, xmlResult);

        Document readDoc = documentBuilder.parse("./students.xml");
        NodeList readStudents = readDoc.getElementsByTagName("students");
        for (int i = 0; i < readStudents.getLength(); i++) {
            Node readStudent = readStudents.item(i);
            System.out.println(readStudent.getTextContent());

        }
    }
}