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
|
/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
/*
* This file is available under and governed by the GNU General Public
* License version 2 only, as published by the Free Software Foundation.
* However, the following notice accompanied the original version of this
* file:
*
* Written by Doug Lea with assistance from members of JCP JSR-166
* Expert Group and released to the public domain, as explained at
* http://creativecommons.org/publicdomain/zero/1.0/
*/
import java.util.Collection;
import java.util.Map;
import java.util.Set;
import java.util.TreeMap;
import java.util.concurrent.locks.ReentrantReadWriteLock;
/**
* This is an incomplete implementation of a wrapper class
* that places read-write locks around unsynchronized Maps.
* Exists as a sample input for MapLoops test.
*/
public class RWMap implements Map {
private final Map m;
private final ReentrantReadWriteLock rwl = new ReentrantReadWriteLock();
public RWMap(Map m) {
if (m == null)
throw new NullPointerException();
this.m = m;
}
public RWMap() {
this(new TreeMap()); // use TreeMap by default
}
public int size() {
rwl.readLock().lock();
try { return m.size(); }
finally { rwl.readLock().unlock(); }
}
public boolean isEmpty() {
rwl.readLock().lock();
try { return m.isEmpty(); }
finally { rwl.readLock().unlock(); }
}
public Object get(Object key) {
rwl.readLock().lock();
try { return m.get(key); }
finally { rwl.readLock().unlock(); }
}
public boolean containsKey(Object key) {
rwl.readLock().lock();
try { return m.containsKey(key); }
finally { rwl.readLock().unlock(); }
}
public boolean containsValue(Object value) {
rwl.readLock().lock();
try { return m.containsValue(value); }
finally { rwl.readLock().unlock(); }
}
public Set keySet() { // Not implemented
return null;
}
public Set entrySet() { // Not implemented
return null;
}
public Collection values() { // Not implemented
return null;
}
public boolean equals(Object o) {
rwl.readLock().lock();
try { return m.equals(o); }
finally { rwl.readLock().unlock(); }
}
public int hashCode() {
rwl.readLock().lock();
try { return m.hashCode(); }
finally { rwl.readLock().unlock(); }
}
public String toString() {
rwl.readLock().lock();
try { return m.toString(); }
finally { rwl.readLock().unlock(); }
}
public Object put(Object key, Object value) {
rwl.writeLock().lock();
try { return m.put(key, value); }
finally { rwl.writeLock().unlock(); }
}
public Object remove(Object key) {
rwl.writeLock().lock();
try { return m.remove(key); }
finally { rwl.writeLock().unlock(); }
}
public void putAll(Map map) {
rwl.writeLock().lock();
try { m.putAll(map); }
finally { rwl.writeLock().unlock(); }
}
public void clear() {
rwl.writeLock().lock();
try { m.clear(); }
finally { rwl.writeLock().unlock(); }
}
}
|
