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copied!<p>The following example is the simplest case. A sports score is updated in the web browser every two seconds using an ICEfaces push update.</p> <p>The method ScoreManagerBean.postConstruct() is called after the managed bean is constructed for a new session. This method starts a thread that calls PortableRenderer.render(sessionId) every two seconds, causing the new score to be pushed to the web browser. In a real application, the push update would be run in some kind of callback function after receiving a message/trigger that data in the application has changed.</p> <p>Exactly the same concept is used for more complex applications such as news-tickers and ebay-style auction sites.</p> <p>Here is the managed bean class ScoreManagerBean.java:</p> <pre><code>import javax.annotation.PostConstruct; import javax.faces.bean.ManagedBean; import javax.faces.bean.SessionScoped; import javax.faces.context.FacesContext; import javax.servlet.http.HttpSession; import java.util.Random; import org.icefaces.application.PortableRenderer; import org.icefaces.application.PushRenderer; @ManagedBean(name = "scoreManager") @SessionScoped public class ScoreManagerBean { private int m_nPointsA = 0; private int m_nPointsB = 0; private PortableRenderer m_renderer; private String m_sessionId; @PostConstruct public void postConstruct() { FacesContext facesContext = FacesContext.getCurrentInstance(); HttpSession session; session = (HttpSession)facesContext.getExternalContext().getSession(false); m_sessionId = session.getId(); PushRenderer.addCurrentSession(m_sessionId); m_renderer = PushRenderer.getPortableRenderer(facesContext); new BidThread().start(); } public String getCurrentScore() { return m_nPointsA + "-" + m_nPointsB; } private class BidThread extends Thread { public void run() { Random r = new Random(); for (int i = 0; i < 1000; i++) { try { sleep(2000); System.out.println("Score has changed"); if (r.nextInt() % 2 == 0) m_nPointsA++; else m_nPointsB++; m_renderer.render(m_sessionId); } catch (Exception e) { e.printStackTrace(); } } } } } </code></pre> <p>and the web page pushexample.xhtml that displays the current score:</p> <pre><code><html xmlns="http://www.w3.org/1999/xhtml" xmlns:h="http://java.sun.com/jsf/html" xmlns:f="http://java.sun.com/jsf/core" xmlns:icecore="http://www.icefaces.org/icefaces/core" xmlns:ice="http://www.icesoft.com/icefaces/component" xmlns:ui="http://java.sun.com/jsf/facelets"> <h:head> <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"/> </h:head> <h:body> <ice:outputText value="Current score: #{scoreManager.currentScore}"/> </h:body> </html> </code></pre>

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