01: /*
02: * Distributed as part of c3p0 v.0.9.1.2
03: *
04: * Copyright (C) 2005 Machinery For Change, Inc.
05: *
06: * Author: Steve Waldman <swaldman@mchange.com>
07: *
08: * This library is free software; you can redistribute it and/or modify
09: * it under the terms of the GNU Lesser General Public License version 2.1, as
10: * published by the Free Software Foundation.
11: *
12: * This software is distributed in the hope that it will be useful,
13: * but WITHOUT ANY WARRANTY; without even the implied warranty of
14: * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15: * GNU Lesser General Public License for more details.
16: *
17: * You should have received a copy of the GNU Lesser General Public License
18: * along with this software; see the file LICENSE. If not, write to the
19: * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
20: * Boston, MA 02111-1307, USA.
21: */
22:
23: package com.mchange.v2.lang;
24:
25: import com.mchange.v2.log.*;
26: import java.lang.reflect.Method;
27:
28: public final class ThreadUtils {
29: private final static MLogger logger = MLog
30: .getLogger(ThreadUtils.class);
31:
32: final static Method holdsLock;
33:
34: static {
35: Method _holdsLock;
36: try {
37: _holdsLock = Thread.class.getMethod("holdsLock",
38: new Class[] { Object.class });
39: } catch (NoSuchMethodException e) {
40: _holdsLock = null;
41: }
42:
43: holdsLock = _holdsLock;
44: }
45:
46: public static void enumerateAll(Thread[] threads) {
47: ThreadGroupUtils.rootThreadGroup().enumerate(threads);
48: }
49:
50: /**
51: * @returns null if cannot be determined, otherwise true or false
52: */
53: public static Boolean reflectiveHoldsLock(Object o) {
54: try {
55: if (holdsLock == null)
56: return null;
57: else
58: return (Boolean) holdsLock.invoke(null,
59: new Object[] { o });
60: } catch (Exception e) {
61: if (logger.isLoggable(MLevel.FINER))
62: logger
63: .log(
64: MLevel.FINER,
65: "An Exception occurred while trying to call Thread.holdsLock( ... ) reflectively.",
66: e);
67: return null;
68: }
69: }
70:
71: private ThreadUtils() {
72: }
73: }
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