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/* * Copyright 2002-2018 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 * * https://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.springframework.core.io.support; import java.io.IOException; import java.util.Map; import java.util.Properties; import org.springframework.core.env.PropertiesPropertySource; import org.springframework.core.io.DefaultResourceLoader; import org.springframework.core.io.Resource; import org.springframework.lang.Nullable; import org.springframework.util.StringUtils; /** * Subclass of {@link PropertiesPropertySource} that loads a {@link Properties} object * from a given {@link org.springframework.core.io.Resource} or resource location such as * {@code "classpath:/com/myco/foo.properties"} or {@code "file:/path/to/file.xml"}. * * <p>Both traditional and XML-based properties file formats are supported; however, in * order for XML processing to take effect, the underlying {@code Resource}'s * {@link org.springframework.core.io.Resource#getFilename() getFilename()} method must * return a non-{@code null} value that ends in {@code ".xml"}. * * @author Chris Beams * @author Juergen Hoeller * @since 3.1 * @see org.springframework.core.io.Resource * @see org.springframework.core.io.support.EncodedResource */ public class ResourcePropertySource extends PropertiesPropertySource { /** The original resource name, if different from the given name. */ @Nullable private final String resourceName; /** * Create a PropertySource having the given name based on Properties * loaded from the given encoded resource. */ public ResourcePropertySource(String name, EncodedResource resource) throws IOException { super(name, PropertiesLoaderUtils.loadProperties(resource)); this.resourceName = getNameForResource(resource.getResource()); } /** * Create a PropertySource based on Properties loaded from the given resource. * The name of the PropertySource will be generated based on the * {@link Resource#getDescription() description} of the given resource. */ public ResourcePropertySource(EncodedResource resource) throws IOException { super(getNameForResource(resource.getResource()), PropertiesLoaderUtils.loadProperties(resource)); this.resourceName = null; } /** * Create a PropertySource having the given name based on Properties * loaded from the given encoded resource. */ public ResourcePropertySource(String name, Resource resource) throws IOException { super(name, PropertiesLoaderUtils.loadProperties(new EncodedResource(resource))); this.resourceName = getNameForResource(resource); } /** * Create a PropertySource based on Properties loaded from the given resource. * The name of the PropertySource will be generated based on the * {@link Resource#getDescription() description} of the given resource. */ public ResourcePropertySource(Resource resource) throws IOException { super(getNameForResource(resource), PropertiesLoaderUtils.loadProperties(new EncodedResource(resource))); this.resourceName = null; } /** * Create a PropertySource having the given name based on Properties loaded from * the given resource location and using the given class loader to load the * resource (assuming it is prefixed with {@code classpath:}). */ public ResourcePropertySource(String name, String location, ClassLoader classLoader) throws IOException { this(name, new DefaultResourceLoader(classLoader).getResource(location)); } /** * Create a PropertySource based on Properties loaded from the given resource * location and use the given class loader to load the resource, assuming it is * prefixed with {@code classpath:}. The name of the PropertySource will be * generated based on the {@link Resource#getDescription() description} of the * resource. */ public ResourcePropertySource(String location, ClassLoader classLoader) throws IOException { this(new DefaultResourceLoader(classLoader).getResource(location)); } /** * Create a PropertySource having the given name based on Properties loaded from * the given resource location. The default thread context class loader will be * used to load the resource (assuming the location string is prefixed with * {@code classpath:}. */ public ResourcePropertySource(String name, String location) throws IOException { this(name, new DefaultResourceLoader().getResource(location)); } /** * Create a PropertySource based on Properties loaded from the given resource * location. The name of the PropertySource will be generated based on the * {@link Resource#getDescription() description} of the resource. */ public ResourcePropertySource(String location) throws IOException { this(new DefaultResourceLoader().getResource(location)); } private ResourcePropertySource(String name, @Nullable String resourceName, Map<String, Object> source) { super(name, source); this.resourceName = resourceName; } /** * Return a potentially adapted variant of this {@link ResourcePropertySource}, * overriding the previously given (or derived) name with the specified name. * @since 4.0.4 */ public ResourcePropertySource withName(String name) { if (this.name.equals(name)) { return this; } // Store the original resource name if necessary... if (this.resourceName != null) { if (this.resourceName.equals(name)) { return new ResourcePropertySource(this.resourceName, null, this.source); } else { return new ResourcePropertySource(name, this.resourceName, this.source); } } else { // Current name is resource name -> preserve it in the extra field... return new ResourcePropertySource(name, this.name, this.source); } } /** * Return a potentially adapted variant of this {@link ResourcePropertySource}, * overriding the previously given name (if any) with the original resource name * (equivalent to the name generated by the name-less constructor variants). * @since 4.1 */ public ResourcePropertySource withResourceName() { if (this.resourceName == null) { return this; } return new ResourcePropertySource(this.resourceName, null, this.source); } /** * Return the description for the given Resource; if the description is * empty, return the class name of the resource plus its identity hash code. * @see org.springframework.core.io.Resource#getDescription() */ private static String getNameForResource(Resource resource) { String name = resource.getDescription(); if (!StringUtils.hasText(name)) { name = resource.getClass().getSimpleName() + "@" + System.identityHashCode(resource); } return name; } }