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POParsing XML usin SAX in java
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copied!<p>I have this code to parse XML data ..</p> <p>But when startelement and endelement functions are called they don't get the parameters values ( as name parameter don't have any data ) when tying to print the parameters values. it dont't have any value, why ? </p> <p>I call updateArticle function in the following code</p> <pre><code>import java.io.IOException; import java.net.MalformedURLException; import java.net.URL; import java.util.ArrayList; import javax.xml.parsers.ParserConfigurationException; import javax.xml.parsers.SAXParser; import javax.xml.parsers.SAXParserFactory; import org.xml.sax.Attributes; import org.xml.sax.InputSource; import org.xml.sax.SAXException; import org.xml.sax.XMLReader; import org.xml.sax.helpers.DefaultHandler; public class RSSHandler extends DefaultHandler { // Used to define what elements we are currently in private boolean inItem = false; private boolean inTitle = false; private boolean inLink = false; // Feed and Article objects to use for temporary storage private Article currentArticle = new Article(); private Feed currentFeed = new Feed(); // Number of articles added so far private int articlesAdded = 0; private ArrayList<Article> articles = new ArrayList<Article>(); private ArrayList<Feed> feeds = new ArrayList<Feed>(); // Number of articles to download private static final int ARTICLES_LIMIT = 15; // The possible values for targetFlag private static final int TARGET_FEED = 0; private static final int TARGET_ARTICLES = 1; // A flag to know if looking for Articles or Feed name private int targetFlag; public RSSHandler(){ } public void startElement(String uri, String name, String qName,Attributes atts) { if (name.trim().equals("title")) inTitle = true; else if (name.trim().equals("item")) inItem = true; else if (name.trim().equals("link")) inLink = true; System.out.println(name.trim()); } public void endElement(String uri, String name, String qName)throws SAXException { if (name.trim().equals("title")) inTitle = false; else if (name.trim().equals("item")) inItem = false; else if (name.trim().equals("link")) inLink = false; // Check if looking for feed, and if feed is complete if (targetFlag == TARGET_FEED && currentFeed.url != null && currentFeed.title != null) { // We know everything we need to know, so insert feed and exit System.out.println("add current feed"); feeds.add(currentFeed); // throw new SAXException(); } // Check if looking for article, and if article is complete if (targetFlag == TARGET_ARTICLES && currentArticle.url != null && currentArticle.title != null) { Article article = new Article(); article.feedId = currentFeed.id; article.title = currentArticle.title; article.url = currentArticle.url; System.out.print(article.title); articles.add(article); //store articles in database currentArticle.title = null; currentArticle.url = null; // Lets check if we've hit our limit on number of articles articlesAdded++; if (articlesAdded >= ARTICLES_LIMIT) throw new SAXException(); } } public ArrayList<Article> getArticles(){ return this.articles; } public ArrayList<Feed> getFeeds(){ return this.feeds; } public void characters(char ch[], int start, int length) { String chars = (new String(ch).substring(start, start + length)); System.out.println(chars); try { // If not in item, then title/link refers to feed if (!inItem) { if (inTitle) currentFeed.title = chars; } else { if (inLink) currentArticle.url = new URL(chars); if (inTitle) currentArticle.title = chars; } } catch (MalformedURLException e) { } } public void createFeed(URL url) { try { targetFlag = TARGET_FEED; currentFeed.url = url; SAXParserFactory spf = SAXParserFactory.newInstance(); SAXParser sp = spf.newSAXParser(); XMLReader xr = sp.getXMLReader(); xr.setContentHandler(this); xr.parse(new InputSource(url.openStream())); } catch (IOException e) {} catch (SAXException e) {} catch (ParserConfigurationException e) {} } public void updateArticles(Feed feed) { try { targetFlag = TARGET_ARTICLES; currentFeed = feed; System.out.println(feed.url.toString()); SAXParserFactory spf = SAXParserFactory.newInstance(); SAXParser sp = spf.newSAXParser(); XMLReader xr = sp.getXMLReader(); xr.setContentHandler(this); xr.parse(new InputSource(currentFeed.url.openStream())); } catch (IOException e) {} catch (SAXException e) {} catch (ParserConfigurationException e) {} } } </code></pre>

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