001/*
002 * Copyright 2002-2017 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.util.List;
020
021import javax.servlet.http.HttpServletRequest;
022
023import org.apache.commons.logging.Log;
024import org.apache.commons.logging.LogFactory;
025
026import org.springframework.core.io.Resource;
027import org.springframework.lang.Nullable;
028
029/**
030 * Base class for {@link org.springframework.web.servlet.resource.ResourceResolver}
031 * implementations. Provides consistent logging.
032 *
033 * @author Rossen Stoyanchev
034 * @since 4.1
035 */
036public abstract class AbstractResourceResolver implements ResourceResolver {
037
038        protected final Log logger = LogFactory.getLog(getClass());
039
040
041        @Override
042        @Nullable
043        public Resource resolveResource(@Nullable HttpServletRequest request, String requestPath,
044                        List<? extends Resource> locations, ResourceResolverChain chain) {
045
046                return resolveResourceInternal(request, requestPath, locations, chain);
047        }
048
049        @Override
050        @Nullable
051        public String resolveUrlPath(String resourceUrlPath, List<? extends Resource> locations,
052                        ResourceResolverChain chain) {
053
054                return resolveUrlPathInternal(resourceUrlPath, locations, chain);
055        }
056
057
058        @Nullable
059        protected abstract Resource resolveResourceInternal(@Nullable HttpServletRequest request,
060                        String requestPath, List<? extends Resource> locations, ResourceResolverChain chain);
061
062        @Nullable
063        protected abstract String resolveUrlPathInternal(String resourceUrlPath,
064                        List<? extends Resource> locations, ResourceResolverChain chain);
065
066}