o adding a metadata cache

Submitted by: Igor Fedorenko


git-svn-id: https://svn.apache.org/repos/asf/maven/components/trunk@780080 13f79535-47bb-0310-9956-ffa450edef68

maven-core/src/main/java/org/apache/maven/project/artifact/DefaultMavenMetadataCache.java

@@ -0,0 +1,161 @@
+package org.apache.maven.project.artifact;
+
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more contributor license
+ * agreements. See the NOTICE file distributed with this work for additional information regarding
+ * copyright ownership. The ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the License. You may obtain a
+ * copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software distributed under the License
+ * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+ * or implied. See the License for the specific language governing permissions and limitations under
+ * the License.
+ */
+
+
+import java.io.File;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.LinkedHashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+import org.apache.maven.artifact.Artifact;
+import org.apache.maven.artifact.ArtifactUtils;
+import org.apache.maven.artifact.metadata.ResolutionGroup;
+import org.apache.maven.artifact.repository.ArtifactRepository;
+import org.codehaus.plexus.component.annotations.Component;
+
+@Component( role = MavenMetadataCache.class )
+public class DefaultMavenMetadataCache
+    implements MavenMetadataCache
+{
+
+    public static class CacheKey 
+    {
+        Artifact artifact;
+        List<ArtifactRepository> repositories = new ArrayList<ArtifactRepository>();
+
+        CacheKey( Artifact artifact, ArtifactRepository localRepository, List<ArtifactRepository> remoteRepositories )
+        {
+            this.artifact = ArtifactUtils.copyArtifact( artifact );
+            this.repositories.add( localRepository );
+            this.repositories.addAll( remoteRepositories );
+        }
+
+        @Override
+        public int hashCode()
+        {
+            int hash = 17;
+            hash = hash * 31 + artifact.hashCode();
+            hash = hash * 31 + repositories.hashCode();
+
+            return hash;
+        }
+
+        @Override
+        public boolean equals( Object o )
+        {
+            if ( o == this )
+            {
+                return true;
+            }
+            
+            if ( !(o instanceof CacheKey) )
+            {
+                return false;
+            }
+            
+            CacheKey other = (CacheKey) o;
+            
+            return artifact.equals( other.artifact ) && repositories.equals( other.repositories );
+        }
+    }
+
+    public class CacheRecord
+    {
+        Artifact pomArtifact;
+        List<Artifact> artifacts;
+        List<ArtifactRepository> remoteRepositories;
+
+        long length;
+        long timestamp;
+
+        CacheRecord(Artifact pomArtifact, Set<Artifact> artifacts, List<ArtifactRepository> remoteRepositories)
+        {
+            this.pomArtifact = ArtifactUtils.copyArtifact( pomArtifact );
+            this.artifacts = copyArtifacts( artifacts );
+            this.remoteRepositories = new ArrayList<ArtifactRepository>( remoteRepositories );
+
+
+            File pomFile = pomArtifact.getFile();
+            if ( pomFile != null && pomFile.canRead() )
+            {
+                this.length = pomFile.length();
+                this.timestamp = pomFile.lastModified();
+            }
+            else
+            {
+                this.length = -1;
+                this.timestamp = -1;
+            }
+        }
+
+        public boolean isStale()
+        {
+            File pomFile = pomArtifact.getFile();
+            if ( pomFile != null && pomFile.canRead() )
+            {
+                return length != pomFile.length() || timestamp != pomFile.lastModified();
+            }
+
+            return length != -1 || timestamp != -1;
+        }
+    }
+    
+    private Map<CacheKey, CacheRecord> cache = new HashMap<CacheKey, CacheRecord>();
+
+    public ResolutionGroup get( Artifact artifact, ArtifactRepository localRepository,
+                                List<ArtifactRepository> remoteRepositories )
+    {
+        CacheKey cacheKey = new CacheKey( artifact, localRepository, remoteRepositories );
+
+        CacheRecord cacheRecord = cache.get( cacheKey );
+
+        if ( cacheRecord != null && !cacheRecord.isStale() )
+        {
+            Artifact pomArtifact = ArtifactUtils.copyArtifact( cacheRecord.pomArtifact );
+            Set<Artifact> artifacts = new LinkedHashSet<Artifact>( copyArtifacts( cacheRecord.artifacts ) );
+            return new ResolutionGroup( pomArtifact, artifacts , cacheRecord.remoteRepositories );
+        }
+
+        cache.remove( cacheKey );
+
+        return null;
+    }
+
+    public void put( Artifact artifact, ArtifactRepository localRepository,
+                     List<ArtifactRepository> remoteRepositories, ResolutionGroup result )
+    {
+        CacheKey cacheKey = new CacheKey( artifact, localRepository, remoteRepositories );
+        CacheRecord cacheRecord = new CacheRecord( result.getPomArtifact(), result.getArtifacts(), result.getResolutionRepositories() );
+
+        cache.put( cacheKey, cacheRecord );
+    }
+
+    public static List<Artifact> copyArtifacts( Collection<Artifact> artifacts )
+    {
+        ArrayList<Artifact> result = new ArrayList<Artifact>();
+        for ( Artifact artifact : artifacts )
+        {
+            result.add( ArtifactUtils.copyArtifact( artifact ) );
+        }
+        return result;
+    }
+
+}

maven-core/src/main/java/org/apache/maven/project/artifact/MavenMetadataCache.java

@@ -0,0 +1,34 @@
+package org.apache.maven.project.artifact;
+
+import java.util.List;
+
+import org.apache.maven.artifact.Artifact;
+import org.apache.maven.artifact.metadata.ResolutionGroup;
+import org.apache.maven.artifact.repository.ArtifactRepository;
+
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more contributor license
+ * agreements. See the NOTICE file distributed with this work for additional information regarding
+ * copyright ownership. The ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the License. You may obtain a
+ * copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software distributed under the License
+ * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+ * or implied. See the License for the specific language governing permissions and limitations under
+ * the License.
+ */
+
+
+public interface MavenMetadataCache
+{
+
+    ResolutionGroup get( Artifact artifact, ArtifactRepository localRepository,
+                         List<ArtifactRepository> remoteRepositories );
+
+    void put( Artifact artifact, ArtifactRepository localRepository,
+              List<ArtifactRepository> remoteRepositories, ResolutionGroup result );
+
+}

maven-core/src/main/java/org/apache/maven/project/artifact/MavenMetadataSource.java

@@ -71,9 +71,21 @@ public class MavenMetadataSource
     @Requirement
     private Logger logger;
 
+    @Requirement
+    private MavenMetadataCache cache;    
+    
     public ResolutionGroup retrieve( Artifact artifact, ArtifactRepository localRepository, List<ArtifactRepository> remoteRepositories )
         throws ArtifactMetadataRetrievalException
     {
+        /*
+        ResolutionGroup cached = cache.get( artifact, localRepository, remoteRepositories );
+
+        if ( cached != null )
+        {
+            return cached;
+        }
+        */
+                
         List<Dependency> dependencies;
 
         Artifact pomArtifact;
@@ -155,7 +167,11 @@ public class MavenMetadataSource
             }
         }
 
-        return new ResolutionGroup( pomArtifact, artifacts, remoteRepositories );
+        ResolutionGroup result = new ResolutionGroup( pomArtifact, artifacts, remoteRepositories );
+
+        //cache.put( artifact, localRepository, remoteRepositories, result );
+
+        return result;
     }
 
     private String getEffectiveScope( String originalScope, String inheritedScope )