import java.io.*;
import org.w3c.dom.Node;
import org.w3c.dom.*;
import org.xml.sax.*;
import org.xml.sax.SAXException;
import javax.xml.parsers.*;
public class Shopping {
	public void shop(Document doc,String prod_name,String prod_price)
	{
		NodeList n1Name=doc.getElementsByTagName("prod_name");
		Element e;
		int len=n1Name.getLength();
		for(int i=0;i<len;i++)
		{
			e=(Element)n1Name.item(i);
			if(e.getFirstChild().getNodeValue().equals(prod_name))
			{
				e=(Element)e.getNextSibling().getNextSibling().getNextSibling();
				e.getFirstChild().setNodeValue(prod_price);
			}
		}
	}
	public void printDOC(Document doc)
	{
		NodeList n1=doc.getElementsByTagName("*");
		Element e;
		int len;
		len=n1.getLength();
		for(int j=0;j<len;j++)
		{
			e=(Element)n1.item(j);
			System.out.println(e.getTagName()+":"+e.getFirstChild().getNodeValue());
		}

	}
	public static void main(String []argv)
	{
		try
		{
			if(argv.length!=2)
			{
				System.err.println("格式:java Shopping 商品名 價格");
				System.exit(1);
			}
			DocumentBuilderFactory dbfactory=DocumentBuilderFactory.newInstance();
			DocumentBuilder domparser=dbfactory.newDocumentBuilder();
                        Document doc=domparser.parse(new File("products.xml"));
			Shopping us=new Shopping();
			us.shop(doc, argv[0], argv[1]);
			us.printDOC(doc);

		}
              	catch(ParserConfigurationException p)
              	{
                        System.out.println(p.toString());

                }
              	catch(SAXException s)
              	{
              		System.out.println(s.toString());

              	}
              	catch(Exception e)
              	{
                	System.out.println(e.toString());
              	}


	}

}