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1   package org.apache.maven.project;
2   
3   /*
4    * Licensed to the Apache Software Foundation (ASF) under one
5    * or more contributor license agreements.  See the NOTICE file
6    * distributed with this work for additional information
7    * regarding copyright ownership.  The ASF licenses this file
8    * to you under the Apache License, Version 2.0 (the
9    * "License"); you may not use this file except in compliance
10   * with the License.  You may obtain a copy of the License at
11   *
12   *  http://www.apache.org/licenses/LICENSE-2.0
13   *
14   * Unless required by applicable law or agreed to in writing,
15   * software distributed under the License is distributed on an
16   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17   * KIND, either express or implied.  See the License for the
18   * specific language governing permissions and limitations
19   * under the License.
20   */
21  
22  import java.util.Collections;
23  import java.util.List;
24  import java.util.Map;
25  import java.util.Objects;
26  import java.util.concurrent.ConcurrentHashMap;
27  
28  import org.codehaus.plexus.classworlds.realm.ClassRealm;
29  import org.codehaus.plexus.classworlds.realm.NoSuchRealmException;
30  import org.codehaus.plexus.component.annotations.Component;
31  import org.codehaus.plexus.personality.plexus.lifecycle.phase.Disposable;
32  import org.eclipse.aether.graph.DependencyFilter;
33  
34  /**
35   * Default project realm cache implementation. Assumes cached data does not change.
36   */
37  @Component( role = ProjectRealmCache.class )
38  public class DefaultProjectRealmCache
39      implements ProjectRealmCache, Disposable
40  {
41      /**
42       * CacheKey
43       */
44      protected static class CacheKey
45          implements Key
46      {
47  
48          private final List<? extends ClassRealm> extensionRealms;
49  
50          private final int hashCode;
51  
52          public CacheKey( List<? extends ClassRealm> extensionRealms )
53          {
54              this.extensionRealms = ( extensionRealms != null )
55                                         ? Collections.unmodifiableList( extensionRealms )
56                                         : Collections.<ClassRealm>emptyList();
57  
58              this.hashCode = this.extensionRealms.hashCode();
59          }
60  
61          @Override
62          public int hashCode()
63          {
64              return hashCode;
65          }
66  
67          @Override
68          public boolean equals( Object o )
69          {
70              if ( o == this )
71              {
72                  return true;
73              }
74  
75              if ( !( o instanceof CacheKey ) )
76              {
77                  return false;
78              }
79  
80              CacheKey other = (CacheKey) o;
81  
82              return extensionRealms.equals( other.extensionRealms );
83          }
84  
85          @Override
86          public String toString()
87          {
88              return extensionRealms.toString();
89          }
90      }
91  
92      protected final Map<Key, CacheRecord> cache = new ConcurrentHashMap<>();
93  
94      @Override
95      public Key createKey( List<? extends ClassRealm> extensionRealms )
96      {
97          return new CacheKey( extensionRealms );
98      }
99  
100     public CacheRecord get( Key key )
101     {
102         return cache.get( key );
103     }
104 
105     public CacheRecord put( Key key, ClassRealm projectRealm, DependencyFilter extensionArtifactFilter )
106     {
107         Objects.requireNonNull( projectRealm, "projectRealm cannot be null" );
108 
109         if ( cache.containsKey( key ) )
110         {
111             throw new IllegalStateException( "Duplicate project realm for extensions " + key );
112         }
113 
114         CacheRecord record = new CacheRecord( projectRealm, extensionArtifactFilter );
115 
116         cache.put( key, record );
117 
118         return record;
119     }
120 
121     public void flush()
122     {
123         for ( CacheRecord record : cache.values() )
124         {
125             ClassRealm realm = record.getRealm();
126             try
127             {
128                 realm.getWorld().disposeRealm( realm.getId() );
129             }
130             catch ( NoSuchRealmException e )
131             {
132                 // ignore
133             }
134         }
135         cache.clear();
136     }
137 
138     public void register( MavenProject project, Key key, CacheRecord record )
139     {
140         // default cache does not track record usage
141     }
142 
143     @Override
144     public void dispose()
145     {
146         flush();
147     }
148 
149 }