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>