1   /*
2    * Copyright (C) 2008 The Guava Authors
3    *
4    * Licensed under the Apache License, Version 2.0 (the "License");
5    * you may not use this file except in compliance with the License.
6    * You may obtain a copy of the License at
7    *
8    * http://www.apache.org/licenses/LICENSE-2.0
9    *
10   * Unless required by applicable law or agreed to in writing, software
11   * distributed under the License is distributed on an "AS IS" BASIS,
12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13   * See the License for the specific language governing permissions and
14   * limitations under the License.
15   */
16  
17  package com.google.common.collect.testing.features;
18  
19  import com.google.common.annotations.GwtCompatible;
20  import com.google.common.collect.testing.Helpers;
21  
22  import java.lang.annotation.Inherited;
23  import java.lang.annotation.Retention;
24  import java.lang.annotation.RetentionPolicy;
25  import java.util.List;
26  import java.util.Set;
27  
28  /**
29   * Optional features of classes derived from {@code List}.
30   *
31   * @author George van den Driessche
32   */
33  // Enum values use constructors with generic varargs.
34  @SuppressWarnings("unchecked")
35  @GwtCompatible
36  public enum ListFeature implements Feature<List> {
37    SUPPORTS_SET,
38    SUPPORTS_ADD_WITH_INDEX(CollectionFeature.SUPPORTS_ADD),
39    SUPPORTS_REMOVE_WITH_INDEX(CollectionFeature.SUPPORTS_REMOVE),
40  
41    GENERAL_PURPOSE(
42        CollectionFeature.GENERAL_PURPOSE,
43        SUPPORTS_SET,
44        SUPPORTS_ADD_WITH_INDEX,
45        SUPPORTS_REMOVE_WITH_INDEX
46    ),
47  
48    /** Features supported by lists where only removal is allowed. */
49    REMOVE_OPERATIONS(
50        CollectionFeature.REMOVE_OPERATIONS,
51        SUPPORTS_REMOVE_WITH_INDEX
52    );
53  
54    private final Set<Feature<? super List>> implied;
55  
56    ListFeature(Feature<? super List> ... implied) {
57      this.implied = Helpers.copyToSet(implied);
58    }
59  
60    @Override
61    public Set<Feature<? super List>> getImpliedFeatures() {
62      return implied;
63    }
64  
65    @Retention(RetentionPolicy.RUNTIME)
66    @Inherited
67    @TesterAnnotation
68    public @interface Require {
69      ListFeature[] value() default {};
70      ListFeature[] absent() default {};
71    }
72  }