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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.editor;
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   *
54   * @param <PRESENTATION> presentation type.
55   * @param <MODEL> model type.
56   */
57  public class MultiItemConverter<PRESENTATION, MODEL> implements Converter<Set<PRESENTATION>, Set<MODEL>> {
58  
59      private static final Logger log = LoggerFactory.getLogger(MultiItemConverter.class);
60  
61      private Converter delegate;
62  
63      public MultiItemConverter(Converter delegate) {
64          Objects.requireNonNull(delegate);
65          this.delegate = delegate;
66      }
67  
68      @Override
69      public Result<Set<MODEL>> convertToModel(Set<PRESENTATION> value, ValueContext context) {
70          if (CollectionUtils.isEmpty(value)) {
71              return Result.ok(Collections.emptySet());
72          }
73          return Result.ok(value.stream().map(val -> getModelSafely(val, context)).filter(Objects::nonNull).collect(Collectors.toSet()));
74      }
75  
76      @Override
77      public Set<PRESENTATION> convertToPresentation(Set<MODEL> value, ValueContext context) {
78          if (CollectionUtils.isEmpty(value)) {
79              return Collections.emptySet();
80          }
81          return (Set<PRESENTATION>) value.stream().map(v -> delegate.convertToPresentation(v, context)).collect(Collectors.toSet());
82      }
83  
84      private MODEL getModelSafely(PRESENTATION value, ValueContext context)  {
85          try {
86              return (MODEL) delegate.convertToModel(value, context).getOrThrow(e -> new IllegalArgumentException(String.valueOf(e)));
87          } catch (Throwable throwable) {
88              log.info(throwable.getMessage());
89              return null;
90          }
91      }
92  }