001    // Copyright 2011 The Apache Software Foundation
002    //
003    // Licensed under the Apache License, Version 2.0 (the "License");
004    // you may not use this file except in compliance with the License.
005    // You may obtain a copy of the License at
006    //
007    // http://www.apache.org/licenses/LICENSE-2.0
008    //
009    // Unless required by applicable law or agreed to in writing, software
010    // distributed under the License is distributed on an "AS IS" BASIS,
011    // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012    // See the License for the specific language governing permissions and
013    // limitations under the License.
014    
015    package org.apache.tapestry5.internal.services.assets;
016    
017    import java.io.IOException;
018    import java.util.Map;
019    
020    import org.apache.tapestry5.ioc.annotations.Marker;
021    import org.apache.tapestry5.ioc.annotations.Primary;
022    import org.apache.tapestry5.services.assets.ResourceMinimizer;
023    import org.apache.tapestry5.services.assets.StreamableResource;
024    
025    /**
026     * Implementation that delegates, via its configuration, to a real implementation based on the content type of the
027     * resource.
028     */
029    @Marker(Primary.class)
030    public class MasterResourceMinimizer implements ResourceMinimizer
031    {
032        private final Map<String, ResourceMinimizer> configuration;
033    
034        public MasterResourceMinimizer(Map<String, ResourceMinimizer> configuration)
035        {
036            this.configuration = configuration;
037        }
038    
039        /** Does nothing; an override of this service can be installed to provide minimization. */
040        public StreamableResource minimize(StreamableResource resource) throws IOException
041        {
042            ResourceMinimizer minimizer = configuration.get(resource.getContentType());
043    
044            return minimizer == null ? resource : minimizer.minimize(resource);
045        }
046    }