Demo2.xml文档

<书架>

<书>

<书名>什么都不知道</书名>

<作者>某及</作者>

<价钱>100</价钱>

<价钱>100元</价钱>

<价钱>998元</价钱>

<价钱>98</价钱>

</书>

<书>

<书名>毛线</书名>

<作者>小涛</作者>

<价钱>无价之宝</价钱>

</书>

</书架>

public class Demo1 {    //得到第二本书的书名    @Test    public void test() throws Exception{        SAXReader reader = new SAXReader();        Document document = reader.read("src/Demo2.xml");        Element root=document.getRootElement();        Element book=(Element)root.elements("书").get(1);        String bookName=book.element("书名").getText();        System.out.println(bookName);    }        //得到第二本书的属性:
     <书名 id="12" name="asd">
      毛线
         @Test    public void test2() throws Exception{        SAXReader reader=new SAXReader();        Document document=reader.read(new File("src/Demo2.xml"));        Element root=document.getRootElement();        Element book=(Element)root.elements("书").get(1);        String value=book.element("书名").attributeValue("name");        System.out.println(value);            }    @Test    public void test3() throws Exception{        SAXReader reader=new SAXReader();        Document document=reader.read(new File("src/Demo2.xml"));        Element root=document.getRootElement();                Element book=root.element("书");        book.addElement("价钱").addText("998");                 OutputFormat format = OutputFormat.createPrettyPrint();//格式化输入器         format.setEncoding("GB2312");//设置格式化输入的编码                 XMLWriter writer = new XMLWriter(new OutputStreamWriter(new FileOutputStream("src/Demo2.xml"),"GB2312"),format);        writer.write(document);//GB2312        writer.close();            }    @Test    public void test4() throws Exception{        SAXReader reader=new SAXReader();        Document document=reader.read(new File("src/Demo2.xml"));        Element root=document.getRootElement();                Element book=root.element("书");        book.addElement("价钱").addText("98");                 OutputFormat format = OutputFormat.createPrettyPrint();//格式化输入器         format.setEncoding("UTF-8");//设置格式化输入的编码                 XMLWriter writer = new XMLWriter(new FileOutputStream("src/Demo2.xml"),format);        writer.write(document);        writer.close();            }}