1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
|
/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
*
* Copyright (c) 1997-2010 Oracle and/or its affiliates. All rights reserved.
*
* The contents of this file are subject to the terms of either the GNU
* General Public License Version 2 only ("GPL") or the Common Development
* and Distribution License("CDDL") (collectively, the "License"). You
* may not use this file except in compliance with the License. You can
* obtain a copy of the License at
* https://glassfish.dev.java.net/public/CDDL+GPL_1_1.html
* or packager/legal/LICENSE.txt. See the License for the specific
* language governing permissions and limitations under the License.
*
* When distributing the software, include this License Header Notice in each
* file and include the License file at packager/legal/LICENSE.txt.
*
* GPL Classpath Exception:
* Oracle designates this particular file as subject to the "Classpath"
* exception as provided by Oracle in the GPL Version 2 section of the License
* file that accompanied this code.
*
* Modifications:
* If applicable, add the following below the License Header, with the fields
* enclosed by brackets [] replaced by your own identifying information:
* "Portions Copyright [year] [name of copyright owner]"
*
* Contributor(s):
* If you wish your version of this file to be governed by only the CDDL or
* only the GPL Version 2, indicate your decision by adding "[Contributor]
* elects to include this software in this distribution under the [CDDL or GPL
* Version 2] license." If you don't indicate a single choice of license, a
* recipient has the option to distribute your version of this file under
* either the CDDL, the GPL Version 2 or to extend the choice of license to
* its licensees as provided above. However, if you add GPL Version 2 code
* and therefore, elected the GPL Version 2 license, then the option applies
* only if the new code is made subject to such option by the copyright
* holder.
*/
package javax.faces.component;
import java.util.Collection;
import java.util.List;
import java.util.Map;
import java.util.Set;
class TypedCollections {
/**
* Dynamically check that the members of the collection are all
* instances of the given type (or null).
*/
private static boolean checkCollectionMembers(Collection<?> c, Class<?> type) {
for (Object element : c) {
if (element != null && !type.isInstance(element)) {
return false;
}
}
return true;
}
/**
* Dynamically check that the members of the collection are all
* instances of the given type (or null), and that the collection
* itself is of the given collection type.
*
* @param <E>
* the collection's element type
* @param c
* the collection to cast
* @param type
* the class of the collection's element type.
* @return the dynamically-type checked collection.
* @throws java.lang.ClassCastException
*/
@SuppressWarnings("unchecked")
static <E,TypedC extends Collection<E>> TypedC dynamicallyCastCollection(Collection<?> c,
Class<E> type,
Class<TypedC> collectionType) {
if (c == null)
return null;
if (!collectionType.isInstance(c))
throw new ClassCastException(c.getClass().getName());
assert checkCollectionMembers(c, type) :
"The collection contains members with a type other than " + type.getName();
return collectionType.cast(c);
}
/**
* Dynamically check that the members of the list are all instances of
* the given type (or null).
*
* @param <E>
* the list's element type
* @param list
* the list to cast
* @param type
* the class of the list's element type.
* @return the dynamically-type checked list.
* @throws java.lang.ClassCastException
*/
@SuppressWarnings("unchecked")
static <E> List<E> dynamicallyCastList(List<?> list, Class<E> type) {
return dynamicallyCastCollection(list, type, List.class);
}
/**
* Dynamically check that the members of the set are all instances of
* the given type (or null).
*
* @param <E>
* the set's element type
* @param set
* the set to cast
* @param type
* the class of the set's element type.
* @return the dynamically-type checked set.
* @throws java.lang.ClassCastException
*/
@SuppressWarnings("unchecked")
static <E> Set<E> dynamicallyCastSet(Set<?> set,
Class<E> type) {
return dynamicallyCastCollection(set, type, Set.class);
}
/**
* Dynamically check that the keys and values in the map are all
* instances of the correct types (or null).
*
* @param <K>
* the map's key type
* @param <V>
* the map's value type
* @param map
* the map to cast
* @param keyType
* the class of the map's key type.
* @param valueType
* the class of the map's value type.
* @return the dynamically-type checked map.
* @throws java.lang.ClassCastException
*/
@SuppressWarnings("unchecked")
static <K, V> Map<K, V> dynamicallyCastMap(Map<?, ?> map,
Class<K> keyType,
Class<V> valueType) {
if (map == null) {
return null;
}
assert checkCollectionMembers(map.keySet(), keyType) :
"The map contains keys with a type other than " + keyType.getName();
assert checkCollectionMembers(map.values(), valueType) :
"The map contains values with a type other than " + valueType.getName();
return (Map<K, V>) map;
}
}
|
