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
|
/*
* Copyright (c) 2010, 2016, Oracle and/or its affiliates. All rights reserved.
* 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.
*/
import java.util.Properties;
import java.util.concurrent.CyclicBarrier;
import java.util.concurrent.BrokenBarrierException;
import java.io.IOException;
import java.net.URL;
/* @test
* @bug 6977738 8029891
* @summary Test ClassLoader.getResource() that should not deadlock
# if another thread is holding the system properties object
*
* @build GetResource
* @run main GetResource
*/
public class GetResource {
CyclicBarrier go = new CyclicBarrier(2);
CyclicBarrier done = new CyclicBarrier(2);
Thread t1, t2;
public GetResource() {
t1 = new Thread() {
public void run() {
Properties prop = System.getProperties();
synchronized (prop) {
System.out.println("Thread 1 ready");
try {
go.await();
prop.put("property", "value");
prop.store(System.out, "");
done.await(); // keep holding the lock until t2 finishes
} catch (InterruptedException e) {
throw new RuntimeException(e);
} catch (BrokenBarrierException e) {
throw new RuntimeException(e);
} catch (IOException e) {
throw new RuntimeException(e);
}
}
System.out.println("Thread 1 exits");
}
};
t2 = new Thread() {
public void run() {
System.out.println("Thread 2 ready");
try {
go.await(); // wait until t1 holds the lock of the system properties
URL u1 = Thread.currentThread().getContextClassLoader().getResource("unknownresource");
done.await();
} catch (InterruptedException e) {
throw new RuntimeException(e);
} catch (BrokenBarrierException e) {
throw new RuntimeException(e);
}
System.out.println("Thread 2 exits");
}
};
}
public void run() throws Exception {
t1.start();
t2.start();
try {
t1.join();
} catch (InterruptedException e) {
e.printStackTrace();
throw e;
}
try {
t2.join();
} catch (InterruptedException e) {
e.printStackTrace();
throw e;
}
}
public static void main(String[] args) throws Exception {
new GetResource().run();
}
}
|
