DOM解析示例

收藏信息.xml

<?xml version="1.0" encoding="GB2312" standalone="no"?><PhoneInfo>

    <Brand id="0" name="华为">

        <Type name="U8650"/>

        <Type name="HW123"/>

        <Type name="HW321"/>

    </Brand>

    <Brand id="1" name="苹果">

        <Type name="iPhone4"/>

    </Brand>

<Brand id="2" name="三星"><type name="s120"/></Brand></PhoneInfo>

解析示例：

import java.io.FileNotFoundException;

import java.io.FileOutputStream;

import java.io.IOException;

import javax.xml.parsers.DocumentBuilder;

import javax.xml.parsers.DocumentBuilderFactory;

import javax.xml.parsers.ParserConfigurationException;

import javax.xml.transform.OutputKeys;

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 org.w3c.dom.Document;

import org.w3c.dom.Element;

import org.w3c.dom.Node;

import org.w3c.dom.NodeList;

import org.xml.sax.SAXException;

public class ParseXml {

    private Document document;

    //获取DOM树

    public void getDom(){

        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();

            DocumentBuilder builder;

            try {

                builder = factory.newDocumentBuilder();

                document = builder.parse("收藏信息.xml");

            } catch (ParserConfigurationException e) {

                e.printStackTrace();

            } catch (SAXException e) {

                e.printStackTrace();

            } catch (IOException e) {

                e.printStackTrace();

            }

    }

    //遍历XML信息

    public void showInfo(){

        NodeList nodes = document.getElementsByTagName("Brand");

        for(int i=0;i<nodes.getLength();i++){

            Node node = nodes.item(i);

            Element ele = (Element)node;

            String brandName = ele.getAttribute("name");

            System.out.println(brandName);

            NodeList types = ele.getChildNodes();

            for(int j=0;j<types.getLength();j++){

                Node typeNode = types.item(j);

                //如果节点是元素节点时再类型转换

                if(typeNode.getNodeType() == Node.ELEMENT_NODE){

                    Element typeEle = (Element)typeNode;

                    String typeName = typeEle.getAttribute("name");

                    System.out.println(typeName);

                }

            }

        }

    }

    //保存XML

    public void saveXml(String path){

        TransformerFactory factory = TransformerFactory.newInstance();

        try {

            //获取解析器

            Transformer transformer = factory.newTransformer();

            //指定特定的输出格式

            transformer.setOutputProperty(OutputKeys.ENCODING, "GB2312");

            //源

            DOMSource source = new DOMSource(document);

            //目标

            StreamResult result = new StreamResult(new FileOutputStream(path));

            //解析

            transformer.transform(source, result);

        } catch (TransformerConfigurationException e) {

            e.printStackTrace();

        } catch (FileNotFoundException e) {

            e.printStackTrace();

        } catch (TransformerException e) {

            e.printStackTrace();

        }

    }

    //向XML添加节点

    public void addEle(){

        Element Brand = document.createElement("Brand");

        Brand.setAttribute("name", "三星");

        Element type = document.createElement("type");

        type.setAttribute("name", "s120");

        Brand.appendChild(type);

        document.getElementsByTagName("PhoneInfo").item(0).appendChild(Brand);

        saveXml("收藏信息.xml");

    }

    //修改XML元素，为每个Brand节点添加一个ID属性，分别为0,1，2

    public void updateEle(){

        NodeList brand = document.getElementsByTagName("Brand");

        for(int i=0;i<brand.getLength();i++){

            Node node = brand.item(i);

            Element ele = (Element)node;

            ele.setAttribute("id", i+"");

        }

        saveXml("收藏信息.xml");

    }

    //删除手机品牌为华为的相关元素

    public void deleteEle(){

        NodeList brand = document.getElementsByTagName("Brand");

        for(int i=0;i<brand.getLength();i++){

            Node node = brand.item(i);

            Element brandEle = (Element)node;

            if(brandEle.getAttribute("name").equals("华为")){

                brandEle.getParentNode().removeChild(brandEle);

            }

        }

        saveXml("收藏信息.xml");

    }

    public static void main(String[] args) {

        ParseXml px = new ParseXml();

        px.getDom();

        px.showInfo();

//        px.saveXml("wjb.xml");

//        px.addEle();

        px.updateEle();

        px.deleteEle();

    }

}