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
015package org.apache.tapestry5.internal.services.assets;
016
017import java.io.IOException;
018
019import org.apache.tapestry5.internal.services.AssetResourceLocator;
020import org.apache.tapestry5.internal.services.ResourceStreamer;
021import org.apache.tapestry5.ioc.Resource;
022import org.apache.tapestry5.services.ClasspathAssetAliasManager;
023import org.apache.tapestry5.services.Request;
024import org.apache.tapestry5.services.Response;
025import 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 */
033public 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}