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.camel.converter;
018    
019    import java.util.ArrayList;
020    import java.util.Arrays;
021    import java.util.Collection;
022    import java.util.HashMap;
023    import java.util.HashSet;
024    import java.util.Hashtable;
025    import java.util.List;
026    import java.util.Map;
027    import java.util.Properties;
028    import java.util.Set;
029    
030    import org.apache.camel.Converter;
031    
032    /**
033     * Some core java.util Collection based
034     * <a href="http://activemq.apache.org/camel/type-converter.html">Type Converters</a>
035     *
036     * @version $Revision: 660275 $
037     */
038    @Converter
039    public final class CollectionConverter {
040    
041        /**
042         * Utility classes should not have a public constructor.
043         */
044        private CollectionConverter() {
045        }
046    
047        /**
048         * Converts a collection to an array
049         */
050        @Converter
051        public static Object[] toArray(Collection value) {
052            if (value == null) {
053                return null;
054            }
055            return value.toArray();
056        }
057    
058        /**
059         * Converts an array to a collection
060         */
061        @Converter
062        public static List toList(Object[] array) {
063            return Arrays.asList(array);
064        }
065    
066        /**
067         * Converts a collection to a List if it is not already
068         */
069        @Converter
070        public static List toList(Collection collection) {
071            return new ArrayList(collection);
072        }
073    
074        @Converter
075        public static Set toSet(Object[] array) {
076            Set answer = new HashSet();
077            answer.addAll(Arrays.asList(array));
078            return answer;
079        }
080    
081        @Converter
082        public static Set toSet(Collection collection) {
083            return new HashSet(collection);
084        }
085    
086        @Converter
087        public static Set toSet(Map map) {
088            return map.entrySet();
089        }
090    
091        @Converter
092        public static Properties toProperties(Map map) {
093            Properties answer = new Properties();
094            answer.putAll(map);
095            return answer;
096        }
097    
098        @Converter
099        public static Hashtable toHashtable(Map map) {
100            return new Hashtable(map);
101        }
102    
103        @Converter
104        public static HashMap toHashMap(Map map) {
105            return new HashMap(map);
106        }
107    }