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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  
38  import org.springframework.beans.BeansException;
39  import org.springframework.beans.factory.InitializingBean;
40  import org.springframework.context.ApplicationContext;
41  import org.springframework.context.ApplicationContextAware;
42  import org.springframework.web.servlet.HandlerExecutionChain;
43  import org.springframework.web.servlet.HandlerMapping;
44  import org.springframework.web.servlet.handler.AbstractUrlHandlerMapping;
45  import org.springframework.web.servlet.handler.BeanNameUrlHandlerMapping;
46  import org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping;
47  
48  import info.magnolia.module.blossom.support.RepositoryUtils;
49  
50  /**
51   * Detects pre-execution requests and decorates handlers in order to either grab the returned ModelAndView or render
52   * one that was previously returned and now should be rendered.
53   *
54   * @since 0.5
55   */
56  public class BlossomHandlerMapping implements HandlerMapping, InitializingBean, ApplicationContextAware {
57  
58      private ApplicationContext applicationContext;
59      private AbstractUrlHandlerMapping[] targetHandlerMappings;
60      private DirectRenderingVoter directRenderingVoter;
61  
62      public AbstractUrlHandlerMapping[] getTargetHandlerMappings() {
63          return targetHandlerMappings;
64      }
65  
66      public void setTargetHandlerMapping(AbstractUrlHandlerMapping targetHandlerMapping) {
67          this.targetHandlerMappings = new AbstractUrlHandlerMapping[]{targetHandlerMapping};
68      }
69  
70      public void setTargetHandlerMappings(AbstractUrlHandlerMapping[] targetHandlerMappings) {
71          this.targetHandlerMappings = targetHandlerMappings;
72      }
73  
74      public DirectRenderingVoter getDirectRenderingPolicy() {
75          return directRenderingVoter;
76      }
77  
78      public void setDirectRenderingPolicy(DirectRenderingVoter directRenderingVoter) {
79          this.directRenderingVoter = directRenderingVoter;
80      }
81  
82      @Override
83      public HandlerExecutionChain getHandler(HttpServletRequest request) throws Exception {
84  
85          PreexecutionContext preexecutionContext = PreexecutionContextHolder.get(request);
86  
87          // If it's not a pre-execution request we simply delegate to the target HandlerMapping.
88          if (preexecutionContext == null) {
89              return getTargetHandler(request);
90          }
91  
92          // If this is a pre-execution request but not for this paragraph then also delegate.
93          if (!preexecutionContext.getUuid().equals(RepositoryUtils.getLocalContentNodeUuid())) {
94              return getTargetHandler(request);
95          }
96  
97          // If there's already a MAV from a pre-executed handler, it should be rendered now.
98          if (preexecutionContext.isModelAndViewSet()) {
99              return new HandlerExecutionChain(new ModelAndViewReuseController(preexecutionContext));
100         }
101 
102         // At this point we know that we're being called by the BlossomFilter to do pre-execution.
103 
104         // Have the target HandlerMapping return a HandlerExecutionChain.
105         HandlerExecutionChain executionChain = getTargetHandler(request);
106         if (executionChain == null) {
107             return null;
108         }
109 
110         // Return a wrapper that will execute the HandlerExecutionChain and grab it's result.
111         return new HandlerExecutionChain(new ModelAndViewGrabbingController(preexecutionContext, executionChain, directRenderingVoter));
112     }
113 
114     private HandlerExecutionChain getTargetHandler(HttpServletRequest request) throws Exception {
115         for (AbstractUrlHandlerMapping targetHandlerMapping : targetHandlerMappings) {
116             HandlerExecutionChain executionChain = targetHandlerMapping.getHandler(request);
117             if (executionChain != null) {
118                 return executionChain;
119             }
120         }
121         return null;
122     }
123 
124     @Override
125     public void afterPropertiesSet() throws Exception {
126 
127         if (directRenderingVoter == null) {
128             directRenderingVoter = new DefaultDirectRenderingVoter();
129         }
130 
131         if (targetHandlerMappings == null) {
132             this.targetHandlerMappings = new AbstractUrlHandlerMapping[2];
133             this.targetHandlerMappings[0] = (AbstractUrlHandlerMapping) applicationContext.getAutowireCapableBeanFactory().createBean(BeanNameUrlHandlerMapping.class);
134             DefaultAnnotationHandlerMapping defaultAnnotationHandlerMapping = (DefaultAnnotationHandlerMapping) applicationContext.getAutowireCapableBeanFactory().createBean(DefaultAnnotationHandlerMapping.class);
135             defaultAnnotationHandlerMapping.setUseDefaultSuffixPattern(false);
136             this.targetHandlerMappings[1] = defaultAnnotationHandlerMapping;
137         }
138     }
139 
140     @Override
141     public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
142         this.applicationContext = applicationContext;
143     }
144 }