001// Copyright 2005 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.tapestry.asset;
016
017import java.util.Locale;
018
019import org.apache.hivemind.Location;
020import org.apache.hivemind.Resource;
021import org.apache.tapestry.IAsset;
022
023/**
024 * A service which creates an asset. In some cases, the asset is selected based on the Resource
025 * (typically of the component or page specification).
026 * 
027 * @author Howard M. Lewis Ship
028 * @since 4.0
029 */
030public interface AssetFactory
031{
032    /**
033     * Creates a new asset relative to an existing asset.
034     * 
035     * @param baseResource
036     *            the base resource from which an asset path may be calculated. Each type of asset
037     *            is linked to a particular implemenation of {@link Resource}, and generates a
038     *            corresponding implementation of {@link org.apache.tapestry.IAsset}.
039     * @param path
040     *            the path relative to the resource (if no leading slash), or an absolute path
041     *            within the domain of the asset type (i.e, within the classpath, or within the web
042     *            application).
043     * @param locale
044     *            the desired locale of the asset; the closest match will be used.
045     * @param location
046     *            the location to be associated with the returned asset, or null to not attempt to
047     *            localize the asset
048     * @throws org.apache.hivemind.ApplicationRuntimeException
049     *             if no matching asset may be found.
050     */
051    public IAsset createAsset(Resource baseResource, String path, Locale locale, Location location);
052
053    /**
054     * Creates a new asset relative to the root of the domain defined by the type of asset.
055     * 
056     * @param path
057     *            the absolute path for the resource
058     * @param locale
059     *            the locale to localize the asset to, or null for no localization
060     * @param location
061     *            the location used to report any errors
062     * @return an {@link IAsset}
063     */
064    public IAsset createAbsoluteAsset(String path, Locale locale, Location location);
065
066    /**
067     * Creates a new asset based on a known resource.
068     */
069
070    public IAsset createAsset(Resource resource, Location location);
071}