ReactorModelPool.java

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();
        }

    }

}