001// Licensed under the Apache License, Version 2.0 (the "License");
002// you may not use this file except in compliance with the License.
003// You may obtain a copy of the License at
004//
005// http://www.apache.org/licenses/LICENSE-2.0
006//
007// Unless required by applicable law or agreed to in writing, software
008// distributed under the License is distributed on an "AS IS" BASIS,
009// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
010// See the License for the specific language governing permissions and
011// limitations under the License.
012
013package org.apache.tapestry5.services.assets;
014
015import org.apache.tapestry5.ioc.annotations.Primary;
016import org.apache.tapestry5.ioc.annotations.UsesMappedConfiguration;
017
018import java.io.IOException;
019
020/**
021 * Certain kinds of resources can be minimized: this primarily refers to JavaScript and CSS, both of which contain
022 * whitespace, comments and other features that can be reduced.
023 *
024 * The service configuration maps a MIME content type (e.g., "text/javascript") to an appropriate implementation of this
025 * interface. The master service has the @{@link Primary} marker interface.
026 * 
027 * @since 5.3
028 */
029@UsesMappedConfiguration(ResourceMinimizer.class)
030public interface ResourceMinimizer
031{
032    /**
033     * Checks the {@linkplain StreamableResource#getContentType() content type} of the resource and applies an
034     * appropriate minimization to it if possible.
035     * 
036     * @param resource
037     *            to minimize
038     * @return the same resource, or a minimized replacement for the resource
039     * @throws IOException
040     */
041    StreamableResource minimize(StreamableResource resource) throws IOException;
042}