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;
18 
19 import com.google.common.annotations.GwtCompatible;
20 import com.google.common.annotations.GwtIncompatible;
21 
22 import java.io.Serializable;
23 import java.util.Map.Entry;
24 
25 import javax.annotation.Nullable;
26 
27 /**
28  * {@code values()} implementation for {@link ImmutableMap}.
29  *
30  * @author Jesse Wilson
31  * @author Kevin Bourrillion
32  */
33 @GwtCompatible(emulated = true)
34 final class ImmutableMapValues<K, V> extends ImmutableCollection<V> {
35   private final ImmutableMap<K, V> map;
36 
ImmutableMapValues(ImmutableMap<K, V> map)37   ImmutableMapValues(ImmutableMap<K, V> map) {
38     this.map = map;
39   }
40 
41   @Override
size()42   public int size() {
43     return map.size();
44   }
45 
46   @Override
iterator()47   public UnmodifiableIterator<V> iterator() {
48     return Maps.valueIterator(map.entrySet().iterator());
49   }
50 
51   @Override
contains(@ullable Object object)52   public boolean contains(@Nullable Object object) {
53     return object != null && Iterators.contains(iterator(), object);
54   }
55 
56   @Override
isPartialView()57   boolean isPartialView() {
58     return true;
59   }
60 
61   @Override
createAsList()62   ImmutableList<V> createAsList() {
63     final ImmutableList<Entry<K, V>> entryList = map.entrySet().asList();
64     return new ImmutableAsList<V>() {
65       @Override
66       public V get(int index) {
67         return entryList.get(index).getValue();
68       }
69 
70       @Override
71       ImmutableCollection<V> delegateCollection() {
72         return ImmutableMapValues.this;
73       }
74     };
75   }
76 
77   @GwtIncompatible("serialization")
78   @Override Object writeReplace() {
79     return new SerializedForm<V>(map);
80   }
81 
82   @GwtIncompatible("serialization")
83   private static class SerializedForm<V> implements Serializable {
84     final ImmutableMap<?, V> map;
85     SerializedForm(ImmutableMap<?, V> map) {
86       this.map = map;
87     }
88     Object readResolve() {
89       return map.values();
90     }
91     private static final long serialVersionUID = 0;
92   }
93 }
94