1 /*
2 * *************************************************************************************************************************************************************
3 *
4 * TheseFoolishThings: Miscellaneous utilities
5 * http://tidalwave.it/projects/thesefoolishthings
6 *
7 * Copyright (C) 2009 - 2024 by Tidalwave s.a.s. (http://tidalwave.it)
8 *
9 * *************************************************************************************************************************************************************
10 *
11 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License.
12 * You may obtain a copy of the License at
13 *
14 * http://www.apache.org/licenses/LICENSE-2.0
15 *
16 * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
17 * CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.
18 *
19 * *************************************************************************************************************************************************************
20 *
21 * git clone https://bitbucket.org/tidalwave/thesefoolishthings-src
22 * git clone https://github.com/tidalwave-it/thesefoolishthings-src
23 *
24 * *************************************************************************************************************************************************************
25 */
26 package it.tidalwave.util.impl.finder;
27
28 import javax.annotation.Nonnull;
29 import javax.annotation.concurrent.Immutable;
30 import java.util.List;
31 import java.util.function.Function;
32 import it.tidalwave.util.Finder;
33 import it.tidalwave.util.spi.SimpleFinderSupport;
34 import static java.util.stream.Collectors.*;
35
36 /***************************************************************************************************************************************************************
37 *
38 * A {@link Finder} which retrieve results from another instance applying a {@link Function}.
39 *
40 * @author Fabrizio Giudici
41 *
42 **************************************************************************************************************************************************************/
43 @Immutable
44 public final class MappingFinder<T, U> extends SimpleFinderSupport<T>
45 {
46 private static final long serialVersionUID = -6359683808082070089L;
47
48 @Nonnull
49 private final Finder<? extends U> delegate;
50
51 @Nonnull
52 private final Function<? super U, ? extends T> decorator;
53
54 public MappingFinder (@Nonnull final Finder<? extends U> delegate,
55 @Nonnull final Function<? super U, ? extends T> decorator)
56 {
57 this.delegate = delegate;
58 this.decorator = decorator;
59 }
60
61 public MappingFinder (@Nonnull final MappingFinder<T, ?> other, @Nonnull final Object override)
62 {
63 super(other, override);
64 final MappingFinder<T, U> source = getSource(MappingFinder.class, other, override);
65 this.delegate = source.delegate;
66 this.decorator = source.decorator;
67 }
68
69 @Override @Nonnull
70 protected List<T> computeResults()
71 {
72 return delegate.results().stream().map(decorator).collect(toList());
73 }
74 }