001    package org.apache.maven.plugin;
002    
003    /*
004     * Licensed to the Apache Software Foundation (ASF) under one
005     * or more contributor license agreements.  See the NOTICE file
006     * distributed with this work for additional information
007     * regarding copyright ownership.  The ASF licenses this file
008     * to you under the Apache License, Version 2.0 (the
009     * "License"); you may not use this file except in compliance
010     * with the License.  You may obtain a copy of the License at
011     *
012     *   http://www.apache.org/licenses/LICENSE-2.0
013     *
014     * Unless required by applicable law or agreed to in writing,
015     * software distributed under the License is distributed on an
016     * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
017     * KIND, either express or implied.  See the License for the
018     * specific language governing permissions and limitations
019     * under the License.
020     */
021    
022    import java.util.List;
023    import java.util.Map;
024    
025    import org.apache.maven.artifact.Artifact;
026    import org.apache.maven.model.Plugin;
027    import org.apache.maven.project.MavenProject;
028    import org.codehaus.plexus.classworlds.realm.ClassRealm;
029    import org.eclipse.aether.RepositorySystemSession;
030    import org.eclipse.aether.graph.DependencyFilter;
031    import org.eclipse.aether.repository.RemoteRepository;
032    
033    /**
034     * Caches plugin class realms. <strong>Warning:</strong> This is an internal utility interface that is only public for
035     * technical reasons, it is not part of the public API. In particular, this interface can be changed or deleted without
036     * prior notice.
037     * 
038     * @author Igor Fedorenko
039     * @author Benjamin Bentmann
040     */
041    public interface PluginRealmCache
042    {
043    
044        public static class CacheRecord
045        {
046            public final ClassRealm realm;
047    
048            public final List<Artifact> artifacts;
049    
050            public CacheRecord( ClassRealm realm, List<Artifact> artifacts )
051            {
052                this.realm = realm;
053                this.artifacts = artifacts;
054            }
055        }
056    
057        /**
058         * A cache key.
059         */
060        interface Key
061        {
062            // marker interface for cache keys
063        }
064    
065        Key createKey( Plugin plugin, ClassLoader parentRealm, Map<String, ClassLoader> foreignImports,
066                       DependencyFilter dependencyFilter, List<RemoteRepository> repositories,
067                       RepositorySystemSession session );
068    
069        CacheRecord get( Key key );
070    
071        CacheRecord put( Key key, ClassRealm pluginRealm, List<Artifact> pluginArtifacts );
072    
073        void flush();
074    
075        /**
076         * Registers the specified cache record for usage with the given project. Integrators can use the information
077         * collected from this method in combination with a custom cache implementation to dispose unused records from the
078         * cache.
079         * 
080         * @param project The project that employs the plugin realm, must not be {@code null}.
081         * @param record The cache record being used for the project, must not be {@code null}.
082         */
083        void register( MavenProject project, CacheRecord record );
084    
085    }