1 /**
2 * This file Copyright (c) 2018 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.ui.framework.databinding.converter;
35
36 import java.util.Collections;
37 import java.util.Objects;
38 import java.util.Set;
39 import java.util.stream.Collectors;
40
41 import org.apache.commons.collections4.CollectionUtils;
42 import org.slf4j.Logger;
43 import org.slf4j.LoggerFactory;
44
45 import com.vaadin.data.Converter;
46 import com.vaadin.data.Result;
47 import com.vaadin.data.ValueContext;
48
49 /**
50 * Converts from multiple instances of the model type to multiple instances of the presentation type and vice versa.
51 * Used e.g. by {@link com.vaadin.ui.MultiSelect multi selection components}.
52 * Delegates to implementations of {@link Converter} handling the single item case.
53 * @see ItemToLinkConverterResolverStrategy
54 *
55 * @param <PRESENTATION> presentation type.
56 * @param <MODEL> model type.
57 */
58 public class MultiItemToLinkConverter<PRESENTATION, MODEL> implements Converter<Set<PRESENTATION>, Set<MODEL>> {
59
60 private static final Logger log = LoggerFactory.getLogger(MultiItemToLinkConverter.class);
61
62 private Converter delegate;
63
64 public MultiItemToLinkConverter(Converter delegate) {
65 Objects.requireNonNull(delegate);
66 this.delegate = delegate;
67 }
68
69 @Override
70 public Result<Set<MODEL>> convertToModel(Set<PRESENTATION> value, ValueContext context) {
71 if (CollectionUtils.isEmpty(value)) {
72 return Result.ok(Collections.emptySet());
73 }
74 return Result.ok(value.stream().map(val -> getModelSafely(val, context)).filter(Objects::nonNull).collect(Collectors.toSet()));
75 }
76
77 @Override
78 public Set<PRESENTATION> convertToPresentation(Set<MODEL> value, ValueContext context) {
79 if (CollectionUtils.isEmpty(value)) {
80 return Collections.emptySet();
81 }
82 return (Set<PRESENTATION>) value.stream().map(v -> delegate.convertToPresentation(v, context)).collect(Collectors.toSet());
83 }
84
85 private MODEL getModelSafely(PRESENTATION value, ValueContext context) {
86 try {
87 return (MODEL) delegate.convertToModel(value, context).getOrThrow(e -> new IllegalArgumentException(String.valueOf(e)));
88 } catch (Throwable throwable) {
89 log.info(throwable.getMessage());
90 return null;
91 }
92 }
93 }