1 /**
2 * This file Copyright (c) 2016 Magnolia International
3 * Ltd. (http://www.magnolia-cms.com). All rights reserved.
4 *
5 *
6 * This file is dual-licensed under both the Magnolia
7 * Network Agreement and the GNU General Public License.
8 * You may elect to use one or the other of these licenses.
9 *
10 * This file is distributed in the hope that it will be
11 * useful, but AS-IS and WITHOUT ANY WARRANTY; without even the
12 * implied warranty of MERCHANTABILITY or FITNESS FOR A
13 * PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT.
14 * Redistribution, except as permitted by whichever of the GPL
15 * or MNA you select, is prohibited.
16 *
17 * 1. For the GPL license (GPL), you can redistribute and/or
18 * modify this file under the terms of the GNU General
19 * Public License, Version 3, as published by the Free Software
20 * Foundation. You should have received a copy of the GNU
21 * General Public License, Version 3 along with this program;
22 * if not, write to the Free Software Foundation, Inc., 51
23 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
24 *
25 * 2. For the Magnolia Network Agreement (MNA), this file
26 * and the accompanying materials are made available under the
27 * terms of the MNA which accompanies this distribution, and
28 * is available at http://www.magnolia-cms.com/mna.html
29 *
30 * Any modifications to this file must keep this entire header
31 * intact.
32 *
33 */
34 package info.magnolia.config.maputil;
35
36 import java.util.Collection;
37 import java.util.Collections;
38 import java.util.Map;
39
40 import org.apache.commons.lang3.StringUtils;
41 import org.slf4j.Logger;
42 import org.slf4j.LoggerFactory;
43
44 import com.google.common.base.Function;
45 import com.google.common.collect.Maps;
46
47 /**
48 * Simple utility which brings an arbitrary source object to the {@link Map map} representation.
49 *
50 * <ul>
51 * <li>Should the source object be a {@link Map map} already, the operation is trivial;</li>
52 * <li>In case the source object is a {@link Collection collection} it is turned into a map with keys equal to either the values of {@value NAME_PROPERTY_KEY} property or consequent natural numbers;</li>
53 * <li>For any other source type - a log warning is emitted and an empty map is returned.</li>
54 * </ul>
55 *
56 * @param <S> source object type
57 * @param <K> resulting map key type
58 */
59 public class ToMap<S, K> implements Function<S, Map<K, Object>> {
60
61 private static final Logger log = LoggerFactory.getLogger(ToMap.class);
62
63 private static final String NAME_PROPERTY_KEY = "name";
64
65 public static <S, K> Map<K, Object> toMap(S source) {
66 return new ToMap<S, K>().apply(source);
67 }
68
69 @Override
70 public Map<K, Object> apply(S source) {
71
72 if (source instanceof Map) {
73 //noinspection unchecked
74 return (Map<K, Object>) source;
75 }
76
77 if (source instanceof Collection) {
78 //noinspection unchecked
79 return Maps.uniqueIndex((Collection<?>) source, new com.google.common.base.Function() {
80 private int numberNameRepresentation = 0;
81 @Override
82 public Object apply(Object value) {
83 String name = null;
84 if (value instanceof Map) {
85 final Map map = (Map) value;
86 if (map.containsKey(NAME_PROPERTY_KEY)) {
87 name = String.valueOf(map.get(NAME_PROPERTY_KEY));
88 }
89 }
90
91 return StringUtils.defaultIfBlank(name, String.valueOf(numberNameRepresentation++));
92 }
93 });
94 }
95
96 if (source == null) {
97 log.debug("ToMap utility encountered 'null' input, will return empty map...");
98 } else {
99 log.debug("ToMap utility did not manage to convert an object [{}] of type [{}] to a map, will return empty map...", source, source.getClass().getSimpleName());
100 }
101
102 return Collections.emptyMap();
103 }
104 }