1 /*
2 * Copyright (c) 2001, 2008, 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.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23
24 /* @test
25 * @bug 6405995
26 * @summary Unit test for selector wakeup and interruption
27 * @library ..
28 * @key intermittent
29 */
30
31 import java.io.*;
32 import java.net.*;
33 import java.nio.*;
34 import java.nio.channels.*;
35 import java.util.Random;
36
37 public class Wakeup {
38
39 static void sleep(int millis) {
40 try {
41 Thread.sleep(millis);
42 } catch (InterruptedException x) {
43 x.printStackTrace();
44 }
45 }
46
47 static class Sleeper extends TestThread {
48 volatile boolean started = false;
49 volatile int entries = 0;
50 volatile int wakeups = 0;
51 volatile boolean wantInterrupt = false;
52 volatile boolean gotInterrupt = false;
53 volatile Exception exception = null;
54 volatile boolean closed = false;
55 Object gate = new Object();
56
57 Selector sel;
58
59 Sleeper(Selector sel) {
60 super("Sleeper", System.err);
61 this.sel = sel;
62 }
63
64 public void go() throws Exception {
65 started = true;
66 for (;;) {
67 synchronized (gate) { }
68 entries++;
69 try {
70 sel.select();
71 } catch (ClosedSelectorException x) {
72 closed = true;
73 }
74 boolean intr = Thread.currentThread().isInterrupted();
75 wakeups++;
76 System.err.println("Wakeup " + wakeups
77 + (closed ? " (closed)" : "")
78 + (intr ? " (intr)" : ""));
79 if (wakeups > 1000)
80 throw new Exception("Too many wakeups");
81 if (closed)
82 return;
83 if (wantInterrupt) {
84 while (!Thread.interrupted())
85 Thread.yield();
86 gotInterrupt = true;
87 wantInterrupt = false;
88 }
89 }
90 }
91
92 }
93
94 private static int checkedWakeups = 0;
95
96 private static void check(Sleeper sleeper, boolean intr)
97 throws Exception
98 {
99 checkedWakeups++;
100 if (sleeper.wakeups > checkedWakeups) {
101 sleeper.finish(100);
102 throw new Exception("Sleeper has run ahead");
103 }
104 int n = 0;
105 while (sleeper.wakeups < checkedWakeups) {
106 sleep(50);
107 if ((n += 50) > 1000) {
108 sleeper.finish(100);
109 throw new Exception("Sleeper appears to be dead ("
110 + checkedWakeups + ")");
111 }
112 }
113 if (sleeper.wakeups > checkedWakeups) {
114 sleeper.finish(100);
115 throw new Exception("Too many wakeups: Expected "
116 + checkedWakeups
117 + ", got " + sleeper.wakeups);
118 }
119 if (intr) {
120 n = 0;
121 // Interrupts can sometimes be delayed, so wait
122 while (!sleeper.gotInterrupt) {
123 sleep(50);
124 if ((n += 50) > 1000) {
125 sleeper.finish(100);
126 throw new Exception("Interrupt never delivered");
127 }
128 }
129 sleeper.gotInterrupt = false;
130 }
131 System.err.println("Check " + checkedWakeups
132 + (intr ? " (intr " + n + ")" : ""));
133 }
134
135 public static void main(String[] args) throws Exception {
136
137 Selector sel = Selector.open();
138
139 // Wakeup before select
140 sel.wakeup();
141
142 Sleeper sleeper = new Sleeper(sel);
143
144 sleeper.start();
145 while (!sleeper.started)
146 sleep(50);
147
148 check(sleeper, false); // 1
149
150 for (int i = 2; i < 5; i++) {
151 // Wakeup during select
152 sel.wakeup();
153 check(sleeper, false); // 2 .. 4
154 }
155
156 // Double wakeup
157 synchronized (sleeper.gate) {
158 sel.wakeup();
159 check(sleeper, false); // 5
160 sel.wakeup();
161 sel.wakeup();
162 }
163 check(sleeper, false); // 6
164
165 // Interrupt
166 synchronized (sleeper.gate) {
167 sleeper.wantInterrupt = true;
168 sleeper.interrupt();
169 check(sleeper, true); // 7
170 }
171
172 // Interrupt before select
173 while (sleeper.entries < 8)
174 Thread.yield();
175 synchronized (sleeper.gate) {
176 sel.wakeup();
177 check(sleeper, false); // 8
178 sleeper.wantInterrupt = true;
179 sleeper.interrupt();
180 sleep(50);
181 }
182 check(sleeper, true); // 9
183
184 // Close during select
185 while (sleeper.entries < 10)
186 Thread.yield();
187 synchronized (sleeper.gate) {
188 sel.close();
189 check(sleeper, false); // 10
190 }
191
192 if (sleeper.finish(200) == 0)
193 throw new Exception("Test failed");
194 if (!sleeper.closed)
195 throw new Exception("Selector not closed");
196 }
197
198 }