001/* 002 * Copyright 2002-2015 the original author or authors. 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * https://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 */ 016 017package org.springframework.web.servlet.resource; 018 019import java.io.IOException; 020import javax.servlet.http.HttpServletRequest; 021 022import org.springframework.core.io.Resource; 023 024/** 025 * A contract for invoking a chain of {@link ResourceTransformer}s where each resolver 026 * is given a reference to the chain allowing it to delegate when necessary. 027 * 028 * @author Rossen Stoyanchev 029 * @since 4.1 030 */ 031public interface ResourceTransformerChain { 032 033 /** 034 * Return the {@code ResourceResolverChain} that was used to resolve the 035 * {@code Resource} being transformed. This may be needed for resolving 036 * related resources, e.g. links to other resources. 037 */ 038 ResourceResolverChain getResolverChain(); 039 040 /** 041 * Transform the given resource. 042 * @param request the current request 043 * @param resource the candidate resource to transform 044 * @return the transformed or the same resource, never {@code null} 045 * @throws IOException if transformation fails 046 */ 047 Resource transform(HttpServletRequest request, Resource resource) throws IOException; 048 049}