Java HTML/XML - 如何读取Xml属性

import java.io.File;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;

import org.w3c.dom.Document;

public class Main {

  public static void main(String argv[]) throws Exception {
    DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
    DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
    Document doc = dBuilder.parse(new File("data.xml"));
    doc.getDocumentElement().normalize();

    System.out.println("City: "
        + doc.getDocumentElement().getChildNodes().item(0)
            .getFirstChild().getChildNodes().item(0).getAttributes()
            .getNamedItem("data").getNodeValue());

    System.out.println("Postal Code: "
        + doc.getDocumentElement().getChildNodes().item(0)
            .getFirstChild().getChildNodes().item(1).getAttributes()
            .getNamedItem("data").getNodeValue());

    System.out.println("Date: "
        + doc.getDocumentElement().getChildNodes().item(0)
            .getFirstChild().getChildNodes().item(4).getAttributes()
            .getNamedItem("data").getNodeValue());
  }
}