1/*
2 * Copyright (c) 2008, 2011, 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/*
25 * @test
26 * @bug 6576763
27 * @summary (thread) Thread constructors throw undocumented NPE for null name
28 */
29
30/*
31 * Verify that threads constructed with a null thread name do not get added
32 * to the list of unstarted thread for a thread group. We can do this by
33 * checking that a daemon threadGroup is desroyed after its final valid thread
34 * has completed.
35 */
36
37import java.util.concurrent.CountDownLatch;
38import static java.lang.System.out;
39
40public class NullThreadName
41{
42    static CountDownLatch done = new CountDownLatch(1);
43
44    public static void main(String args[]) throws Exception {
45        ThreadGroup tg = new ThreadGroup("chegar-threads");
46        Thread goodThread = new Thread(tg, new GoodThread(), "goodThread");
47        try {
48            Thread badThread = new Thread(tg, new Runnable(){
49                @Override
50                public void run() {} }, null);
51        } catch (NullPointerException npe) {
52            out.println("OK, caught expected " + npe);
53        }
54        tg.setDaemon(true);
55        goodThread.start();
56
57        done.await();
58
59        int count = 0;
60        while (goodThread.isAlive()) {
61            /* Hold off a little to allow the thread to complete */
62            out.println("GoodThread still alive, sleeping...");
63            try { Thread.sleep(2000); }
64            catch (InterruptedException unused) {}
65
66            /* do not wait forever - allow 120 seconds same as jtreg default timeout. */
67            if (count++ > 60)
68                throw new AssertionError("GoodThread is still alive!");
69        }
70
71        if (!tg.isDestroyed()) {
72            throw new AssertionError("Failed: Thread group is not destroyed.");
73        }
74    }
75
76    static class GoodThread implements Runnable
77    {
78        @Override
79        public void run() {
80            out.println("Good Thread started...");
81            out.println("Good Thread finishing");
82            done.countDown();
83        }
84    }
85}
86