实现分解器把订单分解为单独的商品

输入的订单为：

<?xml version="1.0" encoding="UTF-8"?>
<order>
   <date>23/6/2009</date>
   <ordernumber>20090623</ordernumber>
   <customer>
     <id>12345</id>
     <name>chenyuan</name>
   </customer>
   <orderitems>
     <item>
       <quantity>3.0</quantity>
       <itemno>w1234</itemno>
       <description>A widget</description>
     </item>
     <item>
       <quantity>2.0</quantity>
       <itemno>G2345</itemno>
       <description>A Gadget</description>
     </item>
   </orderitems>
</order>

实现分解的代码（自己写的，感觉不是很好，有写的不错的请分享一下）：

package org.xml.filterExam;

import java.io.*;

import javax.xml.parsers.*;
import javax.xml.transform.*;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;

import org.w3c.dom.*;

public class XMLSpliter {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		DocumentBuilderFactory dbf=DocumentBuilderFactory.newInstance();
		try
		{
			TransformerFactory tff=TransformerFactory.newInstance();

			Transformer tf=tff.newTransformer();

			DocumentBuilder db=dbf.newDocumentBuilder();
			Document doc=db.parse(new File("NewFile3.xml"));

			Element eleorder=doc.getDocumentElement();

			NodeList nlItem=eleorder.getElementsByTagName("item");
			int len=nlItem.getLength();
			for(int i=0;i<len;i++)
			{
				Document doc1=db.newDocument();

				Element eleOrderItem=doc1.createElement("orderitem");

				Element eleDate=doc1.createElement("date");
				Element eleOrderNumber=doc1.createElement("ordernumber");
				Element eleID=doc1.createElement("customerid");
				Element eleQuantity=doc1.createElement("quantity");
				Element eleItemno=doc1.createElement("itemno");
				Element eleDescription=doc1.createElement("description");


				Node eledate=eleorder.getElementsByTagName("date").item(0);
				Text textDate=doc1.createTextNode(eledate.getFirstChild().getNodeValue());
				eleDate.appendChild(textDate);
				eleOrderItem.appendChild(eleDate);

				Node eleordernumber=eleorder.getElementsByTagName("ordernumber").item(0);
				Text textOrdernumber=doc1.createTextNode(eleordernumber.getFirstChild().getNodeValue());
				eleOrderNumber.appendChild(textOrdernumber);
				eleOrderItem.appendChild(eleOrderNumber);

				NodeList nlcustomer=eleorder.getElementsByTagName("customer");
				Element elecustomer=(Element)nlcustomer.item(0);
				Node eleid=elecustomer.getElementsByTagName("id").item(0);
				Text textId=doc1.createTextNode(eleid.getFirstChild().getNodeValue());
				eleID.appendChild(textId);
				eleOrderItem.appendChild(eleID);

				Element eleitem=(Element)nlItem.item(i);
				Node elequantity=eleitem.getElementsByTagName("quantity").item(0);
				Node eleitemno=eleitem.getElementsByTagName("itemno").item(0);
				Node eledescription=eleitem.getElementsByTagName("description").item(0);

				Text textQuantity=doc1.createTextNode(elequantity.getFirstChild().getNodeValue());
				Text textItemno=doc1.createTextNode(eleitemno.getFirstChild().getNodeValue());
				Text textDescription=doc1.createTextNode(eledescription.getFirstChild().getNodeValue());

				eleQuantity.appendChild(textQuantity);
				eleItemno.appendChild(textItemno);
				eleDescription.appendChild(textDescription);

				eleOrderItem.appendChild(eleQuantity);
				eleOrderItem.appendChild(eleItemno);
				eleOrderItem.appendChild(eleDescription);

				doc1.appendChild(eleOrderItem);

	            DOMSource source=new DOMSource(doc1);

				StreamResult result=new StreamResult(new File("File"+i+".xml"));

				tf.transform(source, result);
			}

		}
		catch(Exception e)
		{
			System.out.println("XMLSpliter has a problem:"+e.toString());
		}
	}

}

输出到两个XML文件中其中File1.xml为：

<?xml version="1.0" encoding="UTF-8" ?> 
- <orderitem>
  <date>23/6/2009</date> 
  <ordernumber>20090623</ordernumber> 
  <customerid>12345</customerid> 
  <quantity>3.0</quantity> 
  <itemno>w1234</itemno> 
  <description>A widget</description> 
  </orderitem>

File2.xml为：

<?xml version="1.0" encoding="UTF-8" ?> 
- <orderitem>
  <date>23/6/2009</date> 
  <ordernumber>20090623</ordernumber> 
  <customerid>12345</customerid> 
  <quantity>2.0</quantity> 
  <itemno>G2345</itemno> 
  <description>A Gadget</description> 
  </orderitem>