import java.io.File;
import java.io.StringWriter;import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
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;public class CreateXML {public static void main(String[] args) {try {//创建xml文件。DOM方式DocumentBuilderFactory factory=DocumentBuilderFactory.newInstance();DocumentBuilder builder=factory.newDocumentBuilder();Document document=builder.newDocument();//添加根元素,指定标签Element root=document.createElement("books");//给根元素添加属性值root.setAttribute("id", "aaa");//创建一个子标签Element book1=document.createElement("book");book1.setAttribute("id", "1");//再创建下一级的子标签Element name1=document.createElement("name");Element price1=document.createElement("price");//设定标签内的内容name1.setTextContent("小说");price1.setTextContent("100元");//把子标签添加到上一级标签,appendChild方法
            book1.appendChild(name1);book1.appendChild(price1);//复制以上代码，把节点填充完Element book2=document.createElement("book");book2.setAttribute("id", "2");Element name2=document.createElement("name");Element price2=document.createElement("price");name2.setTextContent("杂志");price2.setTextContent("200元");book2.appendChild(name2);book2.appendChild(price2);Element book3=document.createElement("book");book3.setAttribute("id", "3");Element name3=document.createElement("name3");Element price3=document.createElement("price3");name3.setTextContent("课本");price3.setTextContent("300元");        book3.appendChild(name3);book3.appendChild(price3);root.appendChild(book1);root.appendChild(book2);root.appendChild(book3);document.appendChild(root);//最后一步//文档内容创建完毕，下面是输出文档TransformerFactory transformerFactory =TransformerFactory.newInstance();Transformer transformer1=transformerFactory.newTransformer();StringWriter writer=new  StringWriter();transformer1.transform(new DOMSource(document), new StreamResult(writer));System.out.println(writer.toString());//成功输出，可以复制//直接生成xml文件transformer1.transform(new DOMSource(document), new StreamResult(new File("newxml.xml")));} catch (ParserConfigurationException e) {e.printStackTrace();} catch (TransformerConfigurationException e) {// TODO 自动生成的 catch 块
            e.printStackTrace();} catch (TransformerException e) {// TODO 自动生成的 catch 块
            e.printStackTrace();}}}

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<books id="aaa">
<book id="1">
<name>小说</name>
<price>100元</price>
</book>
<book id="2">
<name>杂志</name>
<price>200元</price>
</book>
<book id="3">
<name3>课本</name3>
<price3>300元</price3>
</book>
</books>