/* * Copyright 2002-2014 the original author or authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.hotswap.agent.util.spring.io.loader; import org.hotswap.agent.util.spring.io.resource.Resource; import org.hotswap.agent.util.spring.util.ResourceUtils; /** * Strategy interface for loading resources (e.. class path or file system * resources). An {@link org.springframework.context.ApplicationContext} is * required to provide this functionality, plus extended * {@link org.hotswap.agent.util.spring.path.springframework.core.io.support.ResourcePatternResolver} * support. * * <p> * {@link DefaultResourceLoader} is a standalone implementation that is usable * outside an ApplicationContext, also used by {@link ResourceEditor}. * * <p> * Bean properties of type Resource and Resource array can be populated from * Strings when running in an ApplicationContext, using the particular context's * resource loading strategy. * * @author Juergen Hoeller * @since 10.03.2004 * @see Resource * @see org.hotswap.agent.util.spring.path.springframework.core.io.support. * ResourcePatternResolver * @see org.springframework.context.ApplicationContext * @see org.springframework.context.ResourceLoaderAware */ public interface ResourceLoader { /** Pseudo URL prefix for loading from the class path: "classpath:" */ String CLASSPATH_URL_PREFIX = ResourceUtils.CLASSPATH_URL_PREFIX; /** * Return a Resource handle for the specified resource. The handle should * always be a reusable resource descriptor, allowing for multiple * {@link Resource#getInputStream()} calls. * <p> * <ul> * <li>Must support fully qualified URLs, e.g. "file:C:/test.dat". * <li>Must support classpath pseudo-URLs, e.g. "classpath:test.dat". * <li>Should support relative file paths, e.g. "WEB-INF/test.dat". (This * will be implementation-specific, typically provided by an * ApplicationContext implementation.) * </ul> * <p> * Note that a Resource handle does not imply an existing resource; you need * to invoke {@link Resource#exists} to check for existence. * * @param location * the resource location * @return a corresponding Resource handle * @see #CLASSPATH_URL_PREFIX * @see org.hotswap.agent.util.spring.io.resource.springframework.core.io.Resource#exists * @see org.hotswap.agent.util.spring.io.resource.springframework.core.io.Resource#getInputStream */ Resource getResource(String location); /** * Expose the ClassLoader used by this ResourceLoader. * <p> * Clients which need to access the ClassLoader directly can do so in a * uniform manner with the ResourceLoader, rather than relying on the thread * context ClassLoader. * * @return the ClassLoader (only {@code null} if even the system ClassLoader * isn't accessible) * @see org.springframework.util.ClassUtils#getDefaultClassLoader() */ ClassLoader getClassLoader(); }