001    /*
002      GRANITE DATA SERVICES
003      Copyright (C) 2011 GRANITE DATA SERVICES S.A.S.
004    
005      This file is part of Granite Data Services.
006    
007      Granite Data Services is free software; you can redistribute it and/or modify
008      it under the terms of the GNU Library General Public License as published by
009      the Free Software Foundation; either version 2 of the License, or (at your
010      option) any later version.
011    
012      Granite Data Services is distributed in the hope that it will be useful, but
013      WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
014      FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public License
015      for more details.
016    
017      You should have received a copy of the GNU Library General Public License
018      along with this library; if not, see <http://www.gnu.org/licenses/>.
019    */
020    
021    package org.granite.tide.cdi;
022    
023    import javax.enterprise.context.RequestScoped;
024    import javax.enterprise.inject.Default;
025    import javax.enterprise.inject.Instance;
026    import javax.enterprise.inject.Produces;
027    import javax.enterprise.util.AnnotationLiteral;
028    import javax.inject.Inject;
029    import javax.servlet.ServletContext;
030    
031    import org.granite.context.GraniteContext;
032    import org.granite.gravity.Gravity;
033    import org.granite.gravity.GravityManager;
034    import org.granite.messaging.webapp.HttpGraniteContext;
035    
036    
037    /**
038     * TideGravity produces the Gravity instance for injection in CDI beans
039     * 
040     * @author William DRAI
041     */
042    public class TideGravity {
043    
044            @Inject
045            Instance<ServletContext> servletContextInstance;
046            
047        @SuppressWarnings("serial")
048        private static final AnnotationLiteral<Default> DEFAULT_LITERAL = new AnnotationLiteral<Default>() {}; 
049        
050        @Produces @RequestScoped
051        public Gravity getGravity() {
052            
053            ServletContext servletContext = null;
054            
055            if (!servletContextInstance.isUnsatisfied()) {
056                    // Use ServletContext exposed with @Default qualifier (with Seam Servlet for example)
057                    servletContext = servletContextInstance.select(DEFAULT_LITERAL).get();
058            }
059            else {
060                    // If not found, look in GraniteContext
061                    GraniteContext graniteContext = GraniteContext.getCurrentInstance();
062                    if (graniteContext == null || !(graniteContext instanceof HttpGraniteContext))
063                            throw new RuntimeException("Gravity not found: not in a GraniteDS HTTP context");
064                    
065                    servletContext = ((HttpGraniteContext)graniteContext).getServletContext();
066            }
067            
068            return GravityManager.getGravity(servletContext);
069        }
070    }