XML学习经验实例总结2
DTD约束Book.dtd：<!ELEMENT 书架 (书+)><!ELEMENT 书 (书名,价格,介绍)><!ELEMENT 书名 (#PCDATA)><!ELEMENT 价格 (#PCDATA)><!ELEMENT 介绍 (#PCDATA)>为书名设置属性 name（必须）<!ATTLIST 书名 name CDATA #REQUIRED>Book.xml:<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE 书架 SYSTEM "book.dtd"><书架><书><书名 name="wy">计算机科学与技术</书名><价格>36.0</价格><介绍>这本书很好</介绍></书><书><书名 name="ztt">科学管理课</书名><价格>30.0</价格><介绍>这本书挺好</介绍></书><书><书名 name="wu">李清照集注</书名><价格>60.0</价格><介绍>这本书非常好</介绍></书></书架>Jaxp对xml进行DOM解析---读取（1）获取XML中的书名public void read() throws Exception {DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();DocumentBuilder builder = factory.newDocumentBuilder();Document document = builder.parse("src/book.xml");NodeList list = document.getElementsByTagName("书名");Node node = list.item(1);String content = node.getTextContent();System.out.println(content);}（2）获取所有的节点public void read2() throws Exception {DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();DocumentBuilder builder = factory.newDocumentBuilder();Document document = builder.parse("src/book.xml");Node root = document.getElementsByTagName("书架").item(0);list(root);}private void list(Node root) {if(root instanceof Element)System.out.println(root.getNodeName());NodeList list=root.getChildNodes();for(int i=0;i<list.getLength();i++){Node child=list.item(i);list(child);}}（3）获取文档中的属性public void read3() throws Exception {DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();DocumentBuilder builder = factory.newDocumentBuilder();Document document = builder.parse("src/book.xml");Element bookname =(Element) document.getElementsByTagName("书名").item(0);String value=bookname.getAttribute("name");System.out.println(value);}XML解析---增加（1）默认在末尾添加节点@Testpublic void add() throws Exception{DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();DocumentBuilder builder = factory.newDocumentBuilder();Document document = builder.parse("src/book.xml");//创建节点Element ele=document.createElement("价格");ele.setTextContent("10元");//创建节点挂在第一个节点上Element book=(Element)document.getElementsByTagName("书").item(0);book.appendChild(ele);//把更新后内存写回到xml文档TransformerFactory tffactory=TransformerFactory.newInstance();Transformer tf=tffactory.newTransformer();tf.transform(new DOMSource(document), new StreamResult(new FileOutputStream("src/book.xml")));}（2） 在文档指定位置添加节点@Testpublic void add2() throws Exception {DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();DocumentBuilder builder = factory.newDocumentBuilder();Document document = builder.parse("src/book.xml");// 创建节点Element ele = document.createElement("价格");ele.setTextContent("10元");// 得到参考节点Element refNode = (Element) document.getElementsByTagName("价格").item(0);// 得到要挂的节点Element book = (Element) document.getElementsByTagName("书").item(0);// 往book节点的指定位置插孩子节点book.insertBefore(ele, refNode);// 把更新后内存写回到xml文档TransformerFactory tffactory = TransformerFactory.newInstance();Transformer tf = tffactory.newTransformer();tf.transform(new DOMSource(document), new StreamResult(new FileOutputStream("src/book.xml")));}(3) 在文档中为标签添加属性@Testpublic void addAttr() throws Exception {DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();DocumentBuilder builder = factory.newDocumentBuilder();Document document = builder.parse("src/book.xml");Element bookname = (Element) document.getElementsByTagName("书名").item(0);bookname.setAttribute("name", "wy");TransformerFactory tffactory = TransformerFactory.newInstance();Transformer tf = tffactory.newTransformer();tf.transform(new DOMSource(document), new StreamResult(new FileOutputStream("src/book.xml")));}删除1.删除1@Testpublic void delete1() throws Exception {DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();DocumentBuilder builder = factory.newDocumentBuilder();Document document = builder.parse("src/book.xml");// 得到要删除的节点Element ele = (Element) document.getElementsByTagName("价格").item(0);// 得到要删除的节点的父节点Element book = (Element) document.getElementsByTagName("书").item(0);// 父节点删除子节点book.removeChild(ele);TransformerFactory tffactory = TransformerFactory.newInstance();Transformer tf = tffactory.newTransformer();tf.transform(new DOMSource(document), new StreamResult(new FileOutputStream("src/book.xml")));}(2)删除2@Testpublic void delete2() throws Exception {DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();DocumentBuilder builder = factory.newDocumentBuilder();Document document = builder.parse("src/book.xml");// 得到要删除的节点Element ele = (Element) document.getElementsByTagName("价格").item(0);ele.getParentNode().getParentNode().removeChild(ele.getParentNode());TransformerFactory tffactory = TransformerFactory.newInstance();Transformer tf = tffactory.newTransformer();tf.transform(new DOMSource(document), new StreamResult(new FileOutputStream("src/book.xml")));}5更新@Testpublic void update() throws Exception{DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();DocumentBuilder builder = factory.newDocumentBuilder();Document document = builder.parse("src/book.xml");Element ele=(Element)document.getElementsByTagName("价格").item(0);ele.setTextContent("100元");//把更新后的内存写到xml文档中去TransformerFactory tffactory = TransformerFactory.newInstance();Transformer tf = tffactory.newTransformer();tf.transform(new DOMSource(document), new StreamResult(new FileOutputStream("src/book.xml")));}SAX解析XML1.步骤： //创建工厂SAXParserFactory factory=SAXParserFactory.newInstance();//得到解析器SAXParser sp=factory.newSAXParser();//得到读取器XMLReader reader=sp.getXMLReader();//设置内容处理器reader.setContentHandler(new ListHandler());//读取xml文档内容reader.parse("src/book.xml");