ThreadMXBeanTool.java revision 2631:f08b1f0b2f2a 
1/*
2 * Copyright (c) 2015, 2017, 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
24package jdk.test.lib.management;
25
26import java.lang.management.ManagementFactory;
27import java.lang.management.ThreadInfo;
28import java.lang.management.ThreadMXBean;
29
30/**
31 * A few utility methods to use ThreadMXBean.
32 */
33public final class ThreadMXBeanTool {
34
35    /**
36     * Waits until {@link Thread} is in the certain {@link Thread.State}
37     * and blocking on {@code object}.
38     *
39     * @param state The thread state
40     * @param object The object to block on
41     */
42    public static void waitUntilBlockingOnObject(Thread thread, Thread.State state, Object object)
43        throws InterruptedException {
44        String want = object == null ? null : object.getClass().getName() + '@'
45                + Integer.toHexString(System.identityHashCode(object));
46        ThreadMXBean tmx = ManagementFactory.getThreadMXBean();
47        while (thread.isAlive()) {
48            ThreadInfo ti = tmx.getThreadInfo(thread.getId());
49            if (ti.getThreadState() == state
50                    && (want == null || want.equals(ti.getLockName()))) {
51                return;
52            }
53            Thread.sleep(1);
54        }
55    }
56
57    /**
58     * Waits until {@link Thread} is in native.
59     */
60    public static void waitUntilInNative(Thread thread) throws InterruptedException {
61        ThreadMXBean tmx = ManagementFactory.getThreadMXBean();
62        while (thread.isAlive()) {
63            ThreadInfo ti = tmx.getThreadInfo(thread.getId());
64            if (ti.isInNative()) {
65                return;
66            }
67            Thread.sleep(1);
68        }
69    }
70
71}
72