Parsing XML Data with DOM

[Java]Parsing XML Data with DOM

參考資料:http://blog.johnsonlu.org/category/program/java/

Java解析xml或rss的方法有好幾種
這邊紀錄一下透過javax.xml和org.w3c.dom將xml轉換成DOM tree

範例用xml：

1	<?xml version="1.0" encoding="UTF-8"?>

2

<channel>

3	<title>Title</title>

4	<link>http://google.com</link>

5	<description>Description</description>

6	<generator>Codeigniter</generator>

7

<item>

8	<title><![CDATA[XXXXXX]]></title>

9	<link>http://google.com/article/517.html</link>

10	<creator>行政部</creator>

11	<pubDate>Tue, 03 Jul 2012 00:00:01 +0800</pubDate>

12	<description><![CDATA[內文內文]]></description>

13	<category></category>

14

</item>

15	</channel>

Java：

1	import javax.xml.parsers.DocumentBuilderFactory;

2	import javax.xml.parsers.DocumentBuilder;

3	import org.w3c.dom.Document;

4	import org.w3c.dom.NodeList;

5	import org.w3c.dom.Node;

6	import org.w3c.dom.Element;

7

8	public class ParseXML {

9	public static void main(String argv[]) {

10

try {

11	//定義XML DOM parser解析器

12	DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();

13	//建立DOM document

14	DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();

15

//引入xml

16	Document doc = dBuilder.parse("http://test.com/test/test.xml");

17	//針對xml文檔的元素做normalize

18	doc.getDocumentElement().normalize();

19

20

//XML根節點

21	System.out.println("Root Element :" + doc.getDocumentElement().getNodeName());

22

23	//取得所有item元素

24	NodeList nList = doc.getElementsByTagName("item");

25	for (int temp = 0; temp < nList.getLength(); temp++) {

26	//取得該item裡的元素

27	Node nNode = nList.item(temp);

28	if (nNode.getNodeType() == Node.ELEMENT_NODE) {

29	Element eElement = (Element) nNode;

30	System.out.println("Title : " + getTagValue("title", eElement));

31	System.out.println("Link : " + getTagValue("link", eElement));

32	System.out.println("Creator : " + getTagValue("creator", eElement));

33

}

34

}

35	} catch (Exception e) {

36	e.printStackTrace();

37

}

38

}

39	//取得元素的值(過濾掉cdata-section等標記)

40	private static String getTagValue(String sTag, Element eElement) {

41	NodeList nlList = eElement.getElementsByTagName(sTag).item(0).getChildNodes();

42	Node nValue = (Node) nlList.item(0);

43	return nValue.getNodeValue();

44

}

45

46

}