001    /*
002     * Copyright (C) 2006-2007 the original author or authors.
003     *
004     * Licensed under the Apache License, Version 2.0 (the "License");
005     * you may not use this file except in compliance with the License.
006     * You may obtain a copy of the License at
007     *
008     *     http://www.apache.org/licenses/LICENSE-2.0
009     *
010     * Unless required by applicable law or agreed to in writing, software
011     * distributed under the License is distributed on an "AS IS" BASIS,
012     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013     * See the License for the specific language governing permissions and
014     * limitations under the License.
015     */
016    
017    package org.codehaus.gmaven.plugin;
018    
019    import org.codehaus.gmaven.feature.Component;
020    import org.codehaus.gmaven.feature.Configuration;
021    import org.codehaus.gmaven.feature.Feature;
022    
023    /**
024     * Support for Mojo implementations which delegate to a feature component.
025     *
026     * @version $Id: ComponentMojoSupport.java 9 2009-07-16 09:22:08Z user57 $
027     * @author <a href="mailto:jason@planet57.com">Jason Dillon</a>
028     */
029    public abstract class ComponentMojoSupport
030        extends ProviderMojoSupport
031    {
032        private final String key;
033    
034        protected ComponentMojoSupport(final String key) {
035            this.key = key;
036        }
037    
038        private Feature cachedFeature;
039    
040        protected synchronized Feature feature() throws Exception {
041            if (cachedFeature == null) {
042                cachedFeature = feature(key);
043            }
044    
045            return cachedFeature;
046        }
047    
048        protected synchronized Feature feature(final String key) throws Exception {
049            return provider().feature(key);
050        }
051    
052        protected void doExecute() throws Exception {
053            Feature feature = feature();
054    
055            Configuration context = new Configuration();
056            configure(context);
057    
058            Component component = feature.create(context);
059    
060            process(component);
061        }
062    
063        protected void configure(final Configuration context) throws Exception {
064            // Nothing by default
065        }
066    
067        protected abstract void process(Component component) throws Exception;
068    
069    }