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1   /**
2    * This file Copyright (c) 2012-2015 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.ui.api.app.registry;
35  
36  import info.magnolia.config.registry.AbstractRegistry;
37  import info.magnolia.config.registry.DefinitionMetadata;
38  import info.magnolia.config.registry.DefinitionMetadataBuilder;
39  import info.magnolia.config.registry.DefinitionProvider;
40  import info.magnolia.config.registry.DefinitionType;
41  import info.magnolia.event.EventBus;
42  import info.magnolia.event.SystemEventBus;
43  import info.magnolia.ui.api.app.AppDescriptor;
44  
45  import java.util.ArrayList;
46  import java.util.Collection;
47  import java.util.Collections;
48  import java.util.List;
49  import java.util.Set;
50  
51  import javax.inject.Inject;
52  import javax.inject.Named;
53  import javax.inject.Singleton;
54  
55  import org.apache.commons.collections.CollectionUtils;
56  
57  /**
58   * The central registry for {@link AppDescriptor}s. Fires {@link AppRegistryEvent} when the registry changes.
59   *
60   * @see AppDescriptor
61   * @see AppRegistryEvent
62   */
63  @Singleton
64  public class AppDescriptorRegistry extends AbstractRegistry<AppDescriptor> {
65  
66      private EventBus systemEventBus;
67  
68      @Inject
69      public AppDescriptorRegistry(@Named(SystemEventBus.NAME) EventBus systemEventBus) {
70          this.systemEventBus = systemEventBus;
71      }
72  
73      @Override
74      public void register(DefinitionProvider<AppDescriptor> provider) {
75          super.register(provider);
76          sendEvent(AppRegistryEventType.REGISTERED, Collections.singleton(provider.getMetadata()));
77      }
78  
79      //TODO implement unregister method properly once it is present in the parent class.
80      public void unregister(String name) {
81          DefinitionProvider<AppDescriptor> toRemove = getProvider(name);
82          getRegistryMap().remove(toRemove.getMetadata());
83          sendEvent(AppRegistryEventType.UNREGISTERED, Collections.singleton(toRemove.getMetadata()));
84      }
85  
86      /**
87       * @deprecated since 5.4 - use {@link AbstractRegistry#getProvider(String)} method instead.
88       */
89      @Deprecated
90      public AppDescriptor getAppDescriptor(String name) {
91          return getProvider(name).get();
92      }
93  
94      /**
95       * @deprecated since 5.4 - use {@link AbstractRegistry#getProvider(String)} method instead.
96       */
97      @Deprecated
98      public boolean isAppDescriptorRegistered(String name) {
99          try {
100             getProvider(name);
101         } catch (NoSuchDefinitionException | IllegalStateException e) {
102             return false;
103         }
104         return true;
105     }
106 
107     @SuppressWarnings("unchecked")
108     @Override
109     public Set<DefinitionMetadata> unregisterAndRegister(Collection<DefinitionMetadata> metaDataToUnregister, Collection<DefinitionProvider<AppDescriptor>> providersToRegister) {
110 
111         Collection<DefinitionMetadata> metadataBefore = getRegistryMap().keySet();
112         Collection<DefinitionProvider<AppDescriptor>> providersBefore = getRegistryMap().values();
113 
114         Set<DefinitionMetadata> registeredMetaData = super.unregisterAndRegister(metaDataToUnregister, providersToRegister);
115 
116         Collection<DefinitionMetadata> metadataAfter = getRegistryMap().keySet();
117 
118         Collection<DefinitionMetadata> added = CollectionUtils.subtract(metadataAfter, metadataBefore);
119         Collection<DefinitionMetadata> removed = CollectionUtils.subtract(metadataBefore, metadataAfter);
120         Collection<DefinitionMetadata> kept = CollectionUtils.subtract(metadataBefore, removed);
121         Collection<DefinitionMetadata> changed = getAppsThatHaveChanged(kept, providersBefore, providersToRegister);
122 
123         sendEvent(AppRegistryEventType.REGISTERED, added);
124         sendEvent(AppRegistryEventType.UNREGISTERED, removed);
125         sendEvent(AppRegistryEventType.REREGISTERED, changed);
126 
127         return registeredMetaData;
128     }
129 
130     @Override
131     public DefinitionType type() {
132         return DefinitionTypes.APP;
133     }
134 
135     @Override
136     public DefinitionMetadataBuilder newMetadataBuilder() {
137         return DefinitionMetadataBuilder.usingNameAsId();
138     }
139 
140     private Collection<DefinitionMetadata> getAppsThatHaveChanged(Collection<DefinitionMetadata> kept, Collection<DefinitionProvider<AppDescriptor>> providersBefore, Collection<DefinitionProvider<AppDescriptor>> providersToRegister) {
141         final List<DefinitionMetadata> changed = new ArrayList<>();
142         for (DefinitionMetadata metadata : kept) {
143             if (!getAppDescriptor(metadata, providersBefore).equals(getAppDescriptor(metadata, providersToRegister))) {
144                 changed.add(metadata);
145             }
146         }
147         return changed;
148     }
149 
150     private AppDescriptor getAppDescriptor(DefinitionMetadata metadata, Collection<DefinitionProvider<AppDescriptor>> providers) {
151         for (DefinitionProvider<AppDescriptor> provider : providers) {
152             if (provider.getMetadata().equals(metadata)) {
153                 return provider.get();
154             }
155         }
156         return null;
157     }
158 
159     /**
160      * Send an event to the system event bus.
161      */
162     private void sendEvent(AppRegistryEventType eventType, Collection<DefinitionMetadata> appDescriptors) {
163         for (DefinitionMetadata appMetadata : appDescriptors) {
164             systemEventBus.fireEvent(new AppRegistryEvent(appMetadata, eventType));
165         }
166     }
167 }