ViewScopeExtension.java

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package com.sun.faces.application.view;

import com.sun.faces.util.FacesLogger;
import com.sun.faces.util.Util;
import com.sun.faces.util.cdi11.CDIUtil;
import java.util.ServiceLoader;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.enterprise.event.Observes;
import javax.enterprise.inject.spi.AfterBeanDiscovery;
import javax.enterprise.inject.spi.Bean;
import javax.enterprise.inject.spi.BeanManager;
import javax.enterprise.inject.spi.BeforeBeanDiscovery;
import javax.enterprise.inject.spi.Extension;
import javax.enterprise.inject.spi.ProcessBean;
import javax.faces.view.ViewScoped;

/**
 * The CDI extension that makes ViewScoped beans work in a CDI context.
 */
public class ViewScopeExtension implements Extension {

   private boolean isCdiOneOneOrGreater = false;
   private CDIUtil cdiUtil = null;

   /**
     * Stores the logger.
     */
    private static final Logger LOGGER = FacesLogger.APPLICATION_VIEW.getLogger();

    /**
     * Constructor.
     */
    public ViewScopeExtension() {
        if (LOGGER.isLoggable(Level.FINEST)) {
            LOGGER.finest("Constructor @ViewScoped CDI Extension called");
        }
        isCdiOneOneOrGreater = Util.isCdiOneOneOrLater(null);
    }

    /**
     * Processing bean.
     *
     * @param event the event.
     */
    public void processBean(@Observes ProcessBean<?> event) {
        ViewScoped viewScoped = event.getAnnotated().getAnnotation(ViewScoped.class);
        if (viewScoped != null && LOGGER.isLoggable(Level.FINEST)) {
            LOGGER.finest("Processing occurrence of @ViewScoped");
        }

    }
    
    public void beforeBeanDiscovery(@Observes final BeforeBeanDiscovery event, BeanManager beanManager) {
        event.addScope(ViewScoped.class, true, true);
    }

    /**
     * After bean discovery.
     *
     * @param event the event.
     */
    public void afterBeanDiscovery(@Observes final AfterBeanDiscovery event, BeanManager beanManager) {
        if (LOGGER.isLoggable(Level.FINEST)) {
            LOGGER.finest("Adding @ViewScoped context to CDI runtime");
        }
        event.addContext(new ViewScopeContext());
        

       if (isCdiOneOneOrGreater) {
           Class clazz = null;
           try {
               clazz = Class.forName("com.sun.faces.application.view.ViewScopedCDIEventFireHelperImpl");
           } catch (ClassNotFoundException ex) {
               if (LOGGER.isLoggable(Level.SEVERE)) {
                   LOGGER.log(Level.SEVERE, "CDI 1.1 events not enabled", ex);
               }
               return;
           }
           
           if (null == cdiUtil) {
               ServiceLoader<CDIUtil> oneCdiUtil = ServiceLoader.load(CDIUtil.class);
               for (CDIUtil oneAndOnly : oneCdiUtil) {
                   if (null != cdiUtil) {
                       String message = "Must only have one implementation of CDIUtil available";
                       if (LOGGER.isLoggable(Level.SEVERE)) {
                           LOGGER.log(Level.SEVERE, message);
                       }
                       throw new IllegalStateException(message);
                   }
                   cdiUtil = oneAndOnly;
               }
           }
           
           if (null != cdiUtil) {
               Bean bean = cdiUtil.createHelperBean(beanManager, clazz);
               event.addBean(bean);
           } else if (LOGGER.isLoggable(Level.SEVERE)) {
               LOGGER.log(Level.SEVERE, "Unable to obtain CDI 1.1 utilities for Mojarra");
           }
       }
        
    }
    
    
}