通過jaxp方式解析xml文件

1.首先創建一個person.xml文件

<?xml version="1.0" encoding="UTF-8" standalone="no"?><person>
    <p1>
        <name>張大狗</name>
        <age>20</age>
    </p1>
    <p2>
        <name>張三</name>
        <age>20</age>
    </p2>
</person>

 

2.利用Dom對xml文件標籤進行查詢節點、增加節點、更新節點、刪除節點操作。

package my_test;

import java.io.IOException;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;

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

public class TestJasp {

    public static void main(String[] args) throws Exception{
        // 測試獲取xml文件中的<name>節點的值
        selectAll();
        selectOne(1);
        updateOne(0, "張二狗");
        addOne(0, "男");
        DelOne();
    }
    public static void selectOne(int i) throws ParserConfigurationException, SAXException, IOException{
        /*
         *1.創建解析器工廠
         *2.利用解析器工廠創建解析器
         *3.解析xml，返回document對象
         *
         *4.找到所有的name元素，返回一個集合
         *5.定位到某個元素
         */
        DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory.newInstance();
        DocumentBuilder documentBuilder = documentBuilderFactory.newDocumentBuilder();
        Document document = documentBuilder.parse("src/person.xml");
        NodeList list = document.getElementsByTagName("name");
        Node n =list.item(i);
        String name = n.getTextContent();
        System.out.println(name);
    }

    public static void selectAll() throws ParserConfigurationException, SAXException, IOException {
        /*
         *1.創建解析器工廠
         *2.利用解析器工廠創建解析器
         *3.解析xml，返回document對象
         *
         *4.找到所有的name元素，返回一個集合
         *5.遍歷集合，得到每一個name節點
         *6.得到節點name裏面的值
         */
        DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory.newInstance();
        DocumentBuilder documentBuilder = documentBuilderFactory.newDocumentBuilder();
        Document document = documentBuilder.parse("src/person.xml");
        NodeList list = document.getElementsByTagName("name");
        for(int i=0; i<list.getLength();i++) {
            Node node= list.item(i);
            String name = node.getTextContent();
            System.out.println(name);
        }
    }
    
    //更新一個節點的值
    public static void updateOne(int i,String s) throws Exception{
        DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory.newInstance();
        DocumentBuilder documentBuilder = documentBuilderFactory.newDocumentBuilder();
        Document document = documentBuilder.parse("src/person.xml");
        NodeList list = document.getElementsByTagName("name");
        Node node = list.item(i);

        node.setTextContent(s);

        
        //回寫xml文件
        TransformerFactory transformerFactory = TransformerFactory.newInstance();
        Transformer transformer= transformerFactory.newTransformer();
        transformer.transform(new DOMSource(document), new StreamResult("src/person.xml"));
        
        
    }
    
    //添加一個節點
    public static void addOne(int i,String s) throws Exception{
        DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory.newInstance();
        DocumentBuilder documentBuilder = documentBuilderFactory.newDocumentBuilder();
        Document document = documentBuilder.parse("src/person.xml");
        NodeList list = document.getElementsByTagName("p1");
        Node p1 = list.item(i);
        Element sex = document.createElement("sex");
        Text  text = document.createTextNode(s);
        sex.appendChild(text);
        p1.appendChild(sex);
        
        //回寫xml文件
        TransformerFactory transformerFactory = TransformerFactory.newInstance();
        Transformer transformer =transformerFactory.newTransformer();
        transformer.transform(new DOMSource(document), new StreamResult("src/person.xml"));
    }
    
    
    //刪除某個節點
    public static void DelOne() throws ParserConfigurationException, SAXException, IOException, TransformerException{
        DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory.newInstance();
        DocumentBuilder documentBuilder = documentBuilderFactory.newDocumentBuilder();
        Document document = documentBuilder.parse("src/person.xml");
        NodeList list = document.getElementsByTagName("p1");
        Node p1 = list.item(0);
        NodeList list2 = document.getElementsByTagName("sex");
        Node sex =list2.item(0);
        p1.removeChild(sex);
        
        //回寫xml文件
        TransformerFactory transformerFactory = TransformerFactory.newInstance();
        Transformer transformer =transformerFactory.newTransformer();
        transformer.transform(new DOMSource(document), new StreamResult("src/person.xml"));
    }
}