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.Iterator;
026 import java.util.LinkedList;
027 import java.util.List;
028 import java.util.Map;
029 import java.util.Properties;
030 import java.util.Set;
031
032 import org.apache.camel.Converter;
033
034 /**
035 * Some core java.util Collection based
036 * <a href="http://camel.apache.org/type-converter.html">Type Converters</a>
037 *
038 * @version $Revision: 747062 $
039 */
040 @Converter
041 public final class CollectionConverter {
042
043 /**
044 * Utility classes should not have a public constructor.
045 */
046 private CollectionConverter() {
047 }
048
049 /**
050 * Converts a collection to an array
051 */
052 @Converter
053 public static Object[] toArray(Collection value) {
054 if (value == null) {
055 return null;
056 }
057 return value.toArray();
058 }
059
060 /**
061 * Converts an array to a collection
062 */
063 @Converter
064 public static List toList(Object[] array) {
065 return Arrays.asList(array);
066 }
067
068 /**
069 * Converts a collection to a List if it is not already
070 */
071 @Converter
072 @SuppressWarnings("unchecked")
073 public static List toList(Collection collection) {
074 return new ArrayList(collection);
075 }
076
077 /**
078 * Converts an {@link Iterator} to a {@link ArrayList}
079 */
080 @Converter
081 @SuppressWarnings("unchecked")
082 public static ArrayList toArrayList(Iterator it) {
083 ArrayList list = new ArrayList();
084 while (it.hasNext()) {
085 list.add(it.next());
086 }
087 return list;
088 }
089
090 @Converter
091 @SuppressWarnings("unchecked")
092 public static Set toSet(Object[] array) {
093 Set answer = new HashSet();
094 answer.addAll(Arrays.asList(array));
095 return answer;
096 }
097
098 @Converter
099 @SuppressWarnings("unchecked")
100 public static Set toSet(Collection collection) {
101 return new HashSet(collection);
102 }
103
104 @Converter
105 public static Set toSet(Map map) {
106 return map.entrySet();
107 }
108
109 @Converter
110 @SuppressWarnings("unchecked")
111 public static Properties toProperties(Map map) {
112 Properties answer = new Properties();
113 answer.putAll(map);
114 return answer;
115 }
116
117 @Converter
118 @SuppressWarnings("unchecked")
119 public static Hashtable toHashtable(Map map) {
120 return new Hashtable(map);
121 }
122
123 @Converter
124 @SuppressWarnings("unchecked")
125 public static HashMap toHashMap(Map map) {
126 return new HashMap(map);
127 }
128
129 /**
130 * Converts an {@link Iterable} into a {@link List}
131 */
132 @Converter
133 @SuppressWarnings("unchecked")
134 public static List toList(Iterable iterable) {
135 if (iterable instanceof List) {
136 return (List) iterable;
137 }
138 List result = new LinkedList();
139 for (Object value : iterable) {
140 result.add(value);
141 }
142 return result;
143 }
144 }