1 /*
2 * Copyright (c) 2011, 2015, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package test.com.sun.javafx.util;
27
28 import com.sun.javafx.util.WeakReferenceQueue;
29 import com.sun.javafx.util.WeakReferenceQueueShim;
30 import static org.junit.Assert.assertEquals;
31 import static org.junit.Assert.assertFalse;
32 import static org.junit.Assert.assertTrue;
33
34 import java.util.Iterator;
35
36 import org.junit.Test;
37
38 public class WeakReferenceQueueTest {
39 @Test
40 public void testAdd() {
41 WeakReferenceQueue q = new WeakReferenceQueue();
42 String s = new String("Wow!");
43 q.add(s);
44 assertEquals(1, WeakReferenceQueueShim.size(q));
45 }
46
47 @Test
48 public void testRemove() {
49 WeakReferenceQueue q = new WeakReferenceQueue();
50 String a = new String("a");
51 q.add(a);
52 String b = new String("b");
53 q.add(b);
54 String c = new String("c");
55 q.add(c);
56
57 assertEquals(3, WeakReferenceQueueShim.size(q));
58 q.remove(a);
59 q.remove(c);
60 assertEquals(1, WeakReferenceQueueShim.size(q));
61 }
62
63 @Test
64 public void testCleanup() {
65 WeakReferenceQueue q = new WeakReferenceQueue();
66 String a = new String("a");
67 q.add(a);
68 String b = new String("b");
69 q.add(b);
70 String c = new String("c");
71 q.add(c);
72
73 assertEquals(3, WeakReferenceQueueShim.size(q));
74 a = null;
75 c = null;
76 tryGCReallyHard();
77 q.cleanup();
78 assertEquals(1, WeakReferenceQueueShim.size(q));
79 }
80
81 @Test
82 public void testIterator() {
83 WeakReferenceQueue q = new WeakReferenceQueue();
84 String a = new String("a");
85 q.add(a);
86 String b = new String("b");
87 q.add(b);
88 String c = new String("c");
89 q.add(c);
90
91 // This part of the test requires knowledge that iteration
92 // is from last to first
93 Iterator itr = q.iterator();
94 assertTrue(itr.hasNext());
95 assertEquals(c, itr.next());
96 assertTrue(itr.hasNext());
97 assertEquals(b, itr.next());
98 assertTrue(itr.hasNext());
99 assertEquals(a, itr.next());
100 assertFalse(itr.hasNext());
101
102 // and for good measure do it again without calling hasNext just
103 // to make sure calling hasNext isn't a requirement
104 itr = q.iterator();
105 assertEquals(c, itr.next());
106 assertEquals(b, itr.next());
107 assertEquals(a, itr.next());
108 }
109
110 @Test
111 public void testEmptyIterator() {
112 WeakReferenceQueue q = new WeakReferenceQueue();
113 Iterator itr = q.iterator();
114 assertFalse(itr.hasNext());
115 }
116
117 @Test
118 public void testIteratorRemove() {
119 WeakReferenceQueue q = new WeakReferenceQueue();
120 String a = new String("a");
121 q.add(a);
122 String b = new String("b");
123 q.add(b);
124 String c = new String("c");
125 q.add(c);
126
127 Iterator itr = q.iterator();
128 itr.next(); // gives me "c"
129 itr.remove();
130 assertEquals(2, WeakReferenceQueueShim.size(q));
131 itr.next(); // gives me "b"
132 itr.remove();
133 assertEquals(1, WeakReferenceQueueShim.size(q));
134 itr.next(); // gives me "a"
135 itr.remove();
136 assertEquals(0, WeakReferenceQueueShim.size(q));
137
138 q.add(a);
139 q.add(b);
140 q.add(c);
141 itr = q.iterator();
142 itr.next();
143 itr.next(); // gives me "b"
144 itr.remove();
145
146 itr = q.iterator();
147 assertEquals(c, itr.next());
148 assertEquals(a, itr.next());
149 }
150
151 @Test
152 public void testIteratingOverSparseQueue() {
153 WeakReferenceQueue q = new WeakReferenceQueue();
154 String a = new String("a");
155 q.add(a);
156 String b = new String("b");
157 q.add(b);
158 String c = new String("c");
159 q.add(c);
160
161 assertEquals(3, WeakReferenceQueueShim.size(q));
162 a = null;
163 c = null;
164 tryGCReallyHard();
165 q.cleanup();
166
167 Iterator itr = q.iterator();
168 assertEquals(b, itr.next());
169 assertFalse(itr.hasNext());
170 }
171
172 @Test
173 public void testIteratingOverSparseQueueWithoutCleanup() {
174 WeakReferenceQueue q = new WeakReferenceQueue();
175 String a = new String("a");
176 q.add(a);
177 String b = new String("b");
178 q.add(b);
179 String c = new String("c");
180 q.add(c);
181
182 assertEquals(3, WeakReferenceQueueShim.size(q));
183 a = null;
184 c = null;
185 tryGCReallyHard();
186
187 Iterator itr = q.iterator();
188 assertEquals(b, itr.next());
189 assertFalse(itr.hasNext());
190 }
191
192 private void tryGCReallyHard() {
193 // produce some garbage to increase the need of performing gc
194 for (int i = 0; i < 100000; i++) {
195 String s = new String("GARBAGE");
196 }
197
198 // now, yell at the VM to run gc
199 for (int i = 0; i < 10; i++) {
200 System.gc();
201 System.gc();
202 System.gc();
203 }
204
205 // finally, give the VM some idle time to perform gc
206 try { Thread.sleep(100); } catch (InterruptedException e) {}
207
208 // hope that worked!
209 }
210 }