001    /*
002     * Licensed to the Apache Software Foundation (ASF) under one or more
003     * contributor license agreements. See the NOTICE file distributed with
004     * this work for additional information regarding copyright ownership.
005     * The ASF licenses this file to You under the Apache license, Version 2.0
006     * (the "License"); you may not use this file except in compliance with
007     * the License. You may obtain a copy of the License at
008     *
009     *      http://www.apache.org/licenses/LICENSE-2.0
010     *
011     * Unless required by applicable law or agreed to in writing, software
012     * distributed under the License is distributed on an "AS IS" BASIS,
013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     * See the license for the specific language governing permissions and
015     * limitations under the license.
016     */
017    package org.apache.logging.log4j.core.config.plugins;
018    
019    import org.apache.logging.log4j.core.config.Property;
020    import org.apache.logging.log4j.core.lookup.Interpolator;
021    import org.apache.logging.log4j.core.lookup.MapLookup;
022    import org.apache.logging.log4j.core.lookup.StrLookup;
023    
024    import java.util.HashMap;
025    import java.util.Map;
026    
027    /**
028     * Handles properties defined in the configuration.
029     */
030    @Plugin(name = "properties", type = "Core", printObject = true)
031    public final class PropertiesPlugin {
032    
033        private PropertiesPlugin() {
034        }
035    
036        /**
037         * Create the Properties component.
038         * @param properties An array of Property elements.
039         * @return An Interpolator that includes the configuration properties.
040         */
041        @PluginFactory
042        public static StrLookup configureSubstitutor(@PluginElement("properties") Property[] properties) {
043            if (properties == null) {
044                return new Interpolator(null);
045            }
046            Map<String, String> map = new HashMap<String, String>();
047    
048            for (Property prop : properties) {
049                map.put(prop.getName(), prop.getValue());
050            }
051    
052            return new Interpolator(new MapLookup(map));
053        }
054    }