package org.apache.maven.project;
   
   /*
    * 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.HashMap;
  import java.util.Map;
  
  /**
   * Holds all POM files that are known to the reactor. This allows the project builder to resolve imported POMs from the
   * reactor when building another project's effective model.
   * 
   * @author Benjamin Bentmann
   */
  class ReactorModelPool
  {
  
      private final Map<CacheKey, File> pomFiles = new HashMap<CacheKey, File>();
  
      public File get( String groupId, String artifactId, String version )
      {
          return pomFiles.get( new CacheKey( groupId, artifactId, version ) );
      }
  
      public void put( String groupId, String artifactId, String version, File pomFile )
      {
          pomFiles.put( new CacheKey( groupId, artifactId, version ), pomFile );
      }
  
      private static final class CacheKey
      {
  
          private final String groupId;
  
          private final String artifactId;
  
          private final String version;
  
          private final int hashCode;
  
          public CacheKey( String groupId, String artifactId, String version )
          {
              this.groupId = ( groupId != null ) ? groupId : "";
              this.artifactId = ( artifactId != null ) ? artifactId : "";
              this.version = ( version != null ) ? version : "";
  
              int hash = 17;
              hash = hash * 31 + this.groupId.hashCode();
              hash = hash * 31 + this.artifactId.hashCode();
              hash = hash * 31 + this.version.hashCode();
              hashCode = hash;
          }
  
          @Override
          public boolean equals( Object obj )
          {
              if ( this == obj )
              {
                  return true;
              }
  
              if ( !( obj instanceof CacheKey ) )
              {
                  return false;
              }
  
              CacheKey that = (CacheKey) obj;
  
              return artifactId.equals( that.artifactId ) && groupId.equals( that.groupId )
                  && version.equals( that.version );
          }
  
          @Override
          public int hashCode()
          {
              return hashCode;
          }
  
          @Override
          public String toString()
          {
              StringBuilder buffer = new StringBuilder( 96 );
             buffer.append( groupId ).append( ':' ).append( artifactId ).append( ':' ).append( version );
             return buffer.toString();
         }
 
     }
 
 }