001/* 002 * Copyright 2002-2012 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.core.io; 018 019import org.springframework.util.Assert; 020import org.springframework.util.StringUtils; 021 022/** 023 * {@link ResourceLoader} implementation that interprets plain resource paths 024 * as relative to a given {@code java.lang.Class}. 025 * 026 * @author Juergen Hoeller 027 * @since 3.0 028 * @see Class#getResource(String) 029 * @see ClassPathResource#ClassPathResource(String, Class) 030 */ 031public class ClassRelativeResourceLoader extends DefaultResourceLoader { 032 033 private final Class<?> clazz; 034 035 036 /** 037 * Create a new ClassRelativeResourceLoader for the given class. 038 * @param clazz the class to load resources through 039 */ 040 public ClassRelativeResourceLoader(Class<?> clazz) { 041 Assert.notNull(clazz, "Class must not be null"); 042 this.clazz = clazz; 043 setClassLoader(clazz.getClassLoader()); 044 } 045 046 @Override 047 protected Resource getResourceByPath(String path) { 048 return new ClassRelativeContextResource(path, this.clazz); 049 } 050 051 052 /** 053 * ClassPathResource that explicitly expresses a context-relative path 054 * through implementing the ContextResource interface. 055 */ 056 private static class ClassRelativeContextResource extends ClassPathResource implements ContextResource { 057 058 private final Class<?> clazz; 059 060 public ClassRelativeContextResource(String path, Class<?> clazz) { 061 super(path, clazz); 062 this.clazz = clazz; 063 } 064 065 @Override 066 public String getPathWithinContext() { 067 return getPath(); 068 } 069 070 @Override 071 public Resource createRelative(String relativePath) { 072 String pathToUse = StringUtils.applyRelativePath(getPath(), relativePath); 073 return new ClassRelativeContextResource(pathToUse, this.clazz); 074 } 075 } 076 077}