001/*
002 * Copyright 2012-2018 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 *      http://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.boot.env;
018
019import java.io.IOException;
020import java.util.Collections;
021import java.util.List;
022import java.util.Map;
023
024import org.springframework.core.env.PropertySource;
025import org.springframework.core.io.Resource;
026import org.springframework.core.io.support.PropertiesLoaderUtils;
027
028/**
029 * Strategy to load '.properties' files into a {@link PropertySource}.
030 *
031 * @author Dave Syer
032 * @author Phillip Webb
033 * @author Madhura Bhave
034 */
035public class PropertiesPropertySourceLoader implements PropertySourceLoader {
036
037        private static final String XML_FILE_EXTENSION = ".xml";
038
039        @Override
040        public String[] getFileExtensions() {
041                return new String[] { "properties", "xml" };
042        }
043
044        @Override
045        public List<PropertySource<?>> load(String name, Resource resource)
046                        throws IOException {
047                Map<String, ?> properties = loadProperties(resource);
048                if (properties.isEmpty()) {
049                        return Collections.emptyList();
050                }
051                return Collections
052                                .singletonList(new OriginTrackedMapPropertySource(name, properties));
053        }
054
055        @SuppressWarnings({ "unchecked", "rawtypes" })
056        private Map<String, ?> loadProperties(Resource resource) throws IOException {
057                String filename = resource.getFilename();
058                if (filename != null && filename.endsWith(XML_FILE_EXTENSION)) {
059                        return (Map) PropertiesLoaderUtils.loadProperties(resource);
060                }
061                return new OriginTrackedPropertiesLoader(resource).load();
062        }
063
064}