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1   /**
2    * This file Copyright (c) 2003-2011 Magnolia International
3    * Ltd.  (http://www.magnolia-cms.com). All rights reserved.
4    *
5    *
6    * This file is dual-licensed under both the Magnolia
7    * Network Agreement and the GNU General Public License.
8    * You may elect to use one or the other of these licenses.
9    *
10   * This file is distributed in the hope that it will be
11   * useful, but AS-IS and WITHOUT ANY WARRANTY; without even the
12   * implied warranty of MERCHANTABILITY or FITNESS FOR A
13   * PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT.
14   * Redistribution, except as permitted by whichever of the GPL
15   * or MNA you select, is prohibited.
16   *
17   * 1. For the GPL license (GPL), you can redistribute and/or
18   * modify this file under the terms of the GNU General
19   * Public License, Version 3, as published by the Free Software
20   * Foundation.  You should have received a copy of the GNU
21   * General Public License, Version 3 along with this program;
22   * if not, write to the Free Software Foundation, Inc., 51
23   * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
24   *
25   * 2. For the Magnolia Network Agreement (MNA), this file
26   * and the accompanying materials are made available under the
27   * terms of the MNA which accompanies this distribution, and
28   * is available at http://www.magnolia-cms.com/mna.html
29   *
30   * Any modifications to this file must keep this entire header
31   * intact.
32   *
33   */
34  package info.magnolia.module.blossom.preexecution;
35  
36  import javax.servlet.http.HttpServletRequest;
37  import javax.servlet.http.HttpServletResponse;
38  
39  import org.springframework.web.servlet.HandlerAdapter;
40  import org.springframework.web.servlet.HandlerExecutionChain;
41  import org.springframework.web.servlet.HandlerInterceptor;
42  import org.springframework.web.servlet.ModelAndView;
43  import org.springframework.web.servlet.mvc.Controller;
44  
45  import info.magnolia.module.blossom.dispatcher.BlossomDispatcher;
46  import info.magnolia.module.blossom.render.RenderContext;
47  import info.magnolia.module.blossom.template.BlossomRenderable;
48  
49  /**
50   * Wraps a controller that is being pre-executed and stores its resulting ModelAndView internally.
51   *
52   * @since 0.5
53   */
54  public class ModelAndViewGrabbingController implements Controller {
55  
56      private PreexecutionContext preexecutionContext;
57      private HandlerExecutionChain handlerExecutionChain;
58      private DirectRenderingVoter directRenderingVoter;
59  
60      public ModelAndViewGrabbingController(PreexecutionContext preexecutionContext, HandlerExecutionChain handlerExecutionChain, DirectRenderingVoter directRenderingVoter) {
61          this.preexecutionContext = preexecutionContext;
62          this.handlerExecutionChain = handlerExecutionChain;
63          this.directRenderingVoter = directRenderingVoter;
64      }
65  
66      @Override
67      public ModelAndView handleRequest(HttpServletRequest request, HttpServletResponse response) throws Exception {
68  
69          ModelAndView mv = executeChain(handlerExecutionChain, request, response);
70  
71          // If the handler took care of rendering then we're done.
72          if (mv == null) {
73              return null;
74          }
75  
76          // If the handler returned a ModelAndView that should be rendered directly then return it now.
77          if (directRenderingVoter.renderDirectly(mv, request, response)) {
78              return mv;
79          }
80  
81          // Otherwise store the result for later rendering.
82          preexecutionContext.setModelAndView(mv);
83  
84          // Tell the DispatcherServlet that nothing needs to be rendered at this point.
85          return null;
86      }
87  
88      private ModelAndView executeChain(HandlerExecutionChain mappedHandler, HttpServletRequest request, HttpServletResponse response) throws Exception {
89  
90          // Apply preHandle methods of registered interceptors.
91          HandlerInterceptor[] interceptors = mappedHandler.getInterceptors();
92          if (interceptors != null) {
93              for (int i = 0; i < interceptors.length; i++) {
94                  HandlerInterceptor interceptor = interceptors[i];
95                  if (!interceptor.preHandle(request, response, mappedHandler.getHandler())) {
96                      return null;
97                  }
98              }
99          }
100 
101         // Actually invoke the handler.
102         BlossomRenderable renderable = (BlossomRenderable) RenderContext.get().getRenderingContext().getRenderableDefinition();
103         BlossomDispatcher dispatcher = renderable.getDispatcher();
104         HandlerAdapter ha = dispatcher.getHandlerAdapter(mappedHandler.getHandler());
105         ModelAndView mv = ha.handle(request, response, mappedHandler.getHandler());
106 
107         // Apply postHandle methods of registered interceptors.
108         if (interceptors != null) {
109             for (int i = interceptors.length - 1; i >= 0; i--) {
110                 HandlerInterceptor interceptor = interceptors[i];
111                 interceptor.postHandle(request, response, mappedHandler.getHandler(), mv);
112             }
113         }
114 
115         return mv;
116     }
117 }