    001    // Copyright 2010 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
    019    import org.apache.tapestry5.internal.services.AssetResourceLocator;
    020    import org.apache.tapestry5.internal.services.ResourceStreamer;
    021    import org.apache.tapestry5.ioc.Resource;
    022    import org.apache.tapestry5.services.ClasspathAssetAliasManager;
    023    import org.apache.tapestry5.services.Request;
    024    import org.apache.tapestry5.services.Response;
    025    import org.apache.tapestry5.services.assets.AssetRequestHandler;
    026
    027    /**
    028     * A handler for asset requests for classpath assets (within a specific folder).
    029     * Each mapping of the {@link ClasspathAssetAliasManager} gets one of these.
    030     *
    031     * @since 5.2.0
    032     */
    033    public class ClasspathAssetRequestHandler implements AssetRequestHandler
    034    {
    035        private final ResourceStreamer streamer;
    036
    037        private final AssetResourceLocator assetResourceLocator;
    038
    039        private final String baseFolder;
    040
    041        public ClasspathAssetRequestHandler(ResourceStreamer streamer, AssetResourceLocator assetResourceLocator,
    042                String baseFolder)
    043        {
    044            this.streamer = streamer;
    045            this.assetResourceLocator = assetResourceLocator;
    046            this.baseFolder = baseFolder;
    047        }
    048
    049        public boolean handleAssetRequest(Request request, Response response, String extraPath) throws IOException
    050        {
    051            String assetPath = baseFolder + "/" + extraPath;
    052
    053            Resource resource = assetResourceLocator.findClasspathResourceForPath(assetPath);
    054
    055            if (resource == null)
    056                return false;
    057
    058            streamer.streamResource(resource);
    059
    060            return true;
    061        }
    062    }