XML之Dom解析实现增删改查

DOM解析XML实现增删改查

• 新建student.xml

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<students>
    <student id="0">
        <name>wzh</name>
        <age>18</age>
        <sex>男</sex>
    </student>
    <student id="1">
        <name>lld</name>
        <age>20</age>
        <sex>女</sex>
    </student>
</students>

• 新建一个类DomParseXml
• init方法初始化dom

    //创建DOM对象
    private static Document init() throws Exception {
        //借助字节输入流从磁盘获取xml文档到流中
        FileInputStream fileInputStream = new FileInputStream("src/com/bosssoft/hr/train/xml/student.xml");
        //得到DOM工厂实例对象
        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
        //从工厂中获取DOM解析工具
        DocumentBuilder documentBuilder = factory.newDocumentBuilder();
        Document parse = documentBuilder.parse(fileInputStream);
        return parse;
    }

• saveXml对修改的dom进行保存

    //保存xml
    public static void saveXML(Document document,String path) throws TransformerException {
        TransformerFactory transformerFactory = TransformerFactory.newInstance();
        transformerFactory.setAttribute("indent-number", 4);
        Transformer transformer = transformerFactory.newTransformer();
        transformer.setOutputProperty(OutputKeys.INDENT, "YES");
        transformer.transform(new DOMSource(document),new StreamResult(xmlPath+path));
    }

• 查询

//Dom解析，查询
    public static void queryAll() throws Exception {
        Document document = init();
        NodeList studentList = document.getElementsByTagName("student");
        //循环遍历
        for (int i=0; i< studentList.getLength(); i++){
            Node student = studentList.item(i);
            if(student.getNodeType() == Node.ELEMENT_NODE){
                NodeList childNodes = student.getChildNodes();
                for(int j =0; j< childNodes.getLength(); j++){
                    Node child = childNodes.item(j);
                    if(child.getNodeType() == Node.ELEMENT_NODE){
                        String textContent = child.getTextContent();
                        String nodeName = child.getNodeName();
                        System.out.println(nodeName + "-----"+ textContent);
                    }
                }
            }
        }
    }

• 修改

 //通过id查询student 然后修改对应信息
    public static void update(String id,String name,String path) throws Exception {
        Document document = init();
        NodeList StudentList = document.getElementsByTagName("student");
        for(int i = 0; i< StudentList.getLength(); i++){
            Node studentNode = StudentList.item(i);
            Element stu = (Element) studentNode;
            String id1 = stu.getAttribute("id");
            if(id != null && id.equals(id1)){
                NodeList childNodes = studentNode.getChildNodes();
                for(int j = 0; j < childNodes.getLength(); j++){
                    String nodeName = childNodes.item(j).getNodeName();
                    if(nodeName.equals("name")){
                        childNodes.item(j).getFirstChild().setTextContent(name);
                    }
                }
            }
        }
        saveXML(document,path);
        System.out.println("修改成功");
    }

• 增加

    //添加
    public static void add(String idvalue,String username ,String userage, String sex,String path) throws Exception {
        Document document = init();
        Element studentNode = document.createElement("student");
        studentNode.setAttribute("id",idvalue);

        Element nameNode = document.createElement("name");
        Element ageNode = document.createElement("age");
        Element sexNode = document.createElement("sex");

        nameNode.appendChild(document.createTextNode(username));
        ageNode.appendChild(document.createTextNode(userage));
        sexNode.appendChild(document.createTextNode(sex));

        studentNode.appendChild(nameNode);
        studentNode.appendChild(ageNode);
        studentNode.appendChild(sexNode);

        document.getElementsByTagName("students").item(0).appendChild(studentNode);
        saveXML(document,path);
        System.out.println("添加用户成功");
    }

• 删除

 //删除 通过id查询 指定用户删除
    public static void  delete(String id,String path) throws Exception {
        Document document = init();
        NodeList StudentList = document.getElementsByTagName("student");
        for(int i = 0; i< StudentList.getLength(); i++){
            Node studentNode = StudentList.item(i);
            Element stu = (Element) studentNode;
            String id1 = stu.getAttribute("id");
            if(id != null && id.equals(id1)){
                stu.getParentNode().removeChild(stu);
            }
        }
        saveXML(document,path);
        System.out.println("删除成功");
    }

• 完整代码

package com.bosssoft.hr.train.xml;

import org.w3c.dom.*;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.transform.*;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import java.io.FileInputStream;



/**
 * @作者 吴志鸿
 * @maven 3.6.3
 * @jdk 1.8
 */
public class DomParseXml {

    private static String xmlPath = "src/com/bosssoft/hr/train/xml/";

    //创建DOM对象
    private static Document init() throws Exception {
        //借助字节输入流从磁盘获取xml文档到流中
        FileInputStream fileInputStream = new FileInputStream("src/com/bosssoft/hr/train/xml/student.xml");
        //得到DOM工厂实例对象
        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
        //从工厂中获取DOM解析工具
        DocumentBuilder documentBuilder = factory.newDocumentBuilder();
        Document parse = documentBuilder.parse(fileInputStream);
        return parse;
    }

    //Dom解析，查询
    public static void queryAll() throws Exception {
        Document document = init();
        NodeList studentList = document.getElementsByTagName("student");
        //循环遍历
        for (int i=0; i< studentList.getLength(); i++){
            Node student = studentList.item(i);
            if(student.getNodeType() == Node.ELEMENT_NODE){
                NodeList childNodes = student.getChildNodes();
                for(int j =0; j< childNodes.getLength(); j++){
                    Node child = childNodes.item(j);
                    if(child.getNodeType() == Node.ELEMENT_NODE){
                        String textContent = child.getTextContent();
                        String nodeName = child.getNodeName();
                        System.out.println(nodeName + "-----"+ textContent);
                    }
                }
            }
        }
    }

    //保存xml
    public static void saveXML(Document document,String path) throws TransformerException {
        TransformerFactory transformerFactory = TransformerFactory.newInstance();
        transformerFactory.setAttribute("indent-number", 4);
        Transformer transformer = transformerFactory.newTransformer();
        transformer.setOutputProperty(OutputKeys.INDENT, "YES");
        transformer.transform(new DOMSource(document),new StreamResult(xmlPath+path));
    }

    //添加
    public static void add(String idvalue,String username ,String userage, String sex,String path) throws Exception {
        Document document = init();
        Element studentNode = document.createElement("student");
        studentNode.setAttribute("id",idvalue);

        Element nameNode = document.createElement("name");
        Element ageNode = document.createElement("age");
        Element sexNode = document.createElement("sex");

        nameNode.appendChild(document.createTextNode(username));
        ageNode.appendChild(document.createTextNode(userage));
        sexNode.appendChild(document.createTextNode(sex));

        studentNode.appendChild(nameNode);
        studentNode.appendChild(ageNode);
        studentNode.appendChild(sexNode);

        document.getElementsByTagName("students").item(0).appendChild(studentNode);
        saveXML(document,path);
        System.out.println("添加用户成功");
    }

    //通过id查询student 然后修改对应信息
    public static void update(String id,String name,String path) throws Exception {
        Document document = init();
        NodeList StudentList = document.getElementsByTagName("student");
        for(int i = 0; i< StudentList.getLength(); i++){
            Node studentNode = StudentList.item(i);
            Element stu = (Element) studentNode;
            String id1 = stu.getAttribute("id");
            if(id != null && id.equals(id1)){
                NodeList childNodes = studentNode.getChildNodes();
                for(int j = 0; j < childNodes.getLength(); j++){
                    String nodeName = childNodes.item(j).getNodeName();
                    if(nodeName.equals("name")){
                        childNodes.item(j).getFirstChild().setTextContent(name);
                    }
                }
            }
        }
        saveXML(document,path);
        System.out.println("修改成功");
    }

    //删除 通过id查询 指定用户删除
    public static void  delete(String id,String path) throws Exception {
        Document document = init();
        NodeList StudentList = document.getElementsByTagName("student");
        for(int i = 0; i< StudentList.getLength(); i++){
            Node studentNode = StudentList.item(i);
            Element stu = (Element) studentNode;
            String id1 = stu.getAttribute("id");
            if(id != null && id.equals(id1)){
                stu.getParentNode().removeChild(stu);
            }
        }
        saveXML(document,path);
        System.out.println("删除成功");
    }

}