Coverage Summary for Class: SingletonImmutableList (com.google.common.collect)

1 /*
2  * Copyright (C) 2009 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;
18 
19 import static com.google.common.base.Preconditions.checkNotNull;
20 
21 import com.google.common.annotations.GwtCompatible;
22 import com.google.common.base.Preconditions;
23 import java.util.Collections;
24 import java.util.Spliterator;
25 
26 /**
27  * Implementation of {@link ImmutableList} with exactly one element.
28  *
29  * @author Hayward Chan
30  */
31 @GwtCompatible(serializable = true, emulated = true)
32 @SuppressWarnings("serial") // uses writeReplace(), not default serialization
33 @ElementTypesAreNonnullByDefault
34 final class SingletonImmutableList<E> extends ImmutableList<E> {
35 
36   final transient E element;
37 
38   SingletonImmutableList(E element) {
39     this.element = checkNotNull(element);
40   }
41 
42   @Override
43   public E get(int index) {
44     Preconditions.checkElementIndex(index, 1);
45     return element;
46   }
47 
48   @Override
49   public UnmodifiableIterator<E> iterator() {
50     return Iterators.singletonIterator(element);
51   }
52 
53   @Override
54   public Spliterator<E> spliterator() {
55     return Collections.singleton(element).spliterator();
56   }
57 
58   @Override
59   public int size() {
60     return 1;
61   }
62 
63   @Override
64   public ImmutableList<E> subList(int fromIndex, int toIndex) {
65     Preconditions.checkPositionIndexes(fromIndex, toIndex, 1);
66     return (fromIndex == toIndex) ? ImmutableList.<E>of() : this;
67   }
68 
69   @Override
70   public String toString() {
71     return '[' + element.toString() + ']';
72   }
73 
74   @Override
75   boolean isPartialView() {
76     return false;
77   }
78 }