View Javadoc
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.concurrent.ConcurrentHashMap;
26  
27  import org.apache.commons.lang3.Validate;
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      protected static class CacheKey
43          implements Key
44      {
45  
46          private final List<? extends ClassRealm> extensionRealms;
47  
48          private final int hashCode;
49  
50          public CacheKey( List<? extends ClassRealm> extensionRealms )
51          {
52              this.extensionRealms = ( extensionRealms != null ) ? extensionRealms : Collections.<ClassRealm>emptyList();
53  
54              this.hashCode = this.extensionRealms.hashCode();
55          }
56  
57          @Override
58          public int hashCode()
59          {
60              return hashCode;
61          }
62  
63          @Override
64          public boolean equals( Object o )
65          {
66              if ( o == this )
67              {
68                  return true;
69              }
70  
71              if ( !( o instanceof CacheKey ) )
72              {
73                  return false;
74              }
75  
76              CacheKey other = (CacheKey) o;
77  
78              return extensionRealms.equals( other.extensionRealms );
79          }
80  
81          @Override
82          public String toString()
83          {
84              return extensionRealms.toString();
85          }
86      }
87  
88      protected final Map<Key, CacheRecord> cache = new ConcurrentHashMap<>();
89  
90      @Override
91      public Key createKey( List<? extends ClassRealm> extensionRealms )
92      {
93          return new CacheKey( extensionRealms );
94      }
95  
96      public CacheRecord get( Key key )
97      {
98          return cache.get( key );
99      }
100 
101     public CacheRecord put( Key key, ClassRealm projectRealm, DependencyFilter extensionArtifactFilter )
102     {
103         Validate.notNull( projectRealm, "projectRealm cannot be null" );
104 
105         if ( cache.containsKey( key ) )
106         {
107             throw new IllegalStateException( "Duplicate project realm for extensions " + key );
108         }
109 
110         CacheRecord record = new CacheRecord( projectRealm, extensionArtifactFilter );
111 
112         cache.put( key, record );
113 
114         return record;
115     }
116 
117     public void flush()
118     {
119         for ( CacheRecord record : cache.values() )
120         {
121             ClassRealm realm = record.realm;
122             try
123             {
124                 realm.getWorld().disposeRealm( realm.getId() );
125             }
126             catch ( NoSuchRealmException e )
127             {
128                 // ignore
129             }
130         }
131         cache.clear();
132     }
133 
134     public void register( MavenProject project, Key key, CacheRecord record )
135     {
136         // default cache does not track record usage
137     }
138 
139     @Override
140     public void dispose()
141     {
142         flush();
143     }
144 
145 }