27.2. 02.使用DOM

27.2.1. DOM方式读取XML文件

import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;


import java.io.File;

public class ReadXML {
    public static void main(String[] args) {
        try {
            DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
            DocumentBuilder builder = factory.newDocumentBuilder();
            Document document = builder.parse(new File("src/config/language.xml"));//解析文档


            Element root = document.getDocumentElement(); //获取根节点
            System.out.println("language=" + root.getAttribute("cat"));
            System.out.println("-------------");
            NodeList list = root.getElementsByTagName("lan");//获取根节点的标签名为“lan”的子节点
            for (int i = 0; i < list.getLength(); i ++) {
                Element lan =  (Element) list.item(i);  //遍历得到每个"lan"节点
                System.out.println(lan.getTagName()+ "=" + lan.getAttribute("id"));

                NodeList lanList = lan.getChildNodes();  //获取“lan”节点的子节点
                for (int j = 0; j < lanList.getLength(); j++) {
                    Node node = lanList.item(j);
                    if (node instanceof Element) {
                        System.out.println(node.getNodeName()+"="+node.getTextContent());
                    }
                }
                System.out.println("*****************");
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

27.2.2. DOM方式创建XML文件

import org.w3c.dom.Document;
import org.w3c.dom.Element;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerConfigurationException;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import java.io.File;
import java.io.StringWriter;

public class CreateXML {
    public static void main(String[] args) {
        try {
            DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
            DocumentBuilder builder = factory.newDocumentBuilder();
            Document document = builder.newDocument();

            Element languages = document.createElement("languages");
            languages.setAttribute("cat", "it");

            Element lan_1 = document.createElement("lan");
            lan_1.setAttribute("id", "1");

            Element name_1 = document.createElement("name");
            name_1.setTextContent("Java");

            Element ide_1 = document.createElement("ide");
            ide_1.setTextContent("Eclipse");


            lan_1.appendChild(name_1);
            lan_1.appendChild(ide_1);

            languages.appendChild(lan_1);
            document.appendChild(languages);

            //将构建好的xml输出
            TransformerFactory transformerFactory = TransformerFactory.newInstance();
            Transformer transformer = transformerFactory.newTransformer();

            //输出到控制台
            StringWriter writer = new StringWriter();
            transformer.transform(new DOMSource(document), new StreamResult(writer));
            System.out.println(writer.toString());

            //输出到文件
            transformer.transform(new DOMSource(document), new StreamResult(new File("language.xml")));

        } catch (ParserConfigurationException e) {
            e.printStackTrace();
        } catch (TransformerConfigurationException e) {
            e.printStackTrace();
        } catch (TransformerException e) {
            e.printStackTrace();
        }
    }
}

参考文献

https://www.cnblogs.com/lolau/p/7157902.html