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comparison dwtx/core/runtime/jobs/LockListener.d @ 122:9d0585bcb7aa

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Add core.jobs package
author Frank Benoit <benoit@tionex.de>
date Tue, 12 Aug 2008 02:34:21 +0200
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121:c0304616ea23 122:9d0585bcb7aa
1 /*******************************************************************************
2 * Copyright (c) 2004, 2006 IBM Corporation and others.
3 * All rights reserved. This program and the accompanying materials
4 * are made available under the terms of the Eclipse Public License v1.0
5 * which accompanies this distribution, and is available at
6 * http://www.eclipse.org/legal/epl-v10.html
7 *
8 * Contributors:
9 * IBM - Initial API and implementation
10 * Port to the D programming language:
11 * Frank Benoit <benoit@tionex.de>
12 *******************************************************************************/
13 module dwtx.core.runtime.jobs.LockListener;
14
15 import tango.core.Thread;
16 import dwt.dwthelper.utils;
17
18 import dwtx.core.internal.jobs.JobManager;
19 import dwtx.core.internal.jobs.LockManager;
20 import dwtx.core.runtime.jobs.Job;
21
22 /**
23 * A lock listener is notified whenever a thread is about to wait
24 * on a lock, and when a thread is about to release a lock.
25 * <p>
26 * This class is for internal use by the platform-related plug-ins.
27 * Clients outside of the base platform should not reference or subclass this class.
28 * </p>
29 *
30 * @see IJobManager#setLockListener(LockListener)
31 * @since 3.0
32 */
33 public class LockListener {
34 private const LockManager manager;
35
36 public this(){
37 manager = (cast(JobManager)Job.getJobManager()).getLockManager();
38 }
39
40 /**
41 * Notification that a thread is about to block on an attempt to acquire a lock.
42 * Returns whether the thread should be granted immediate access to the lock.
43 * <p>
44 * This default implementation always returns <code>false</code>.
45 * Subclasses may override.
46 *
47 * @param lockOwner the thread that currently owns the lock this thread is
48 * waiting for, or <code>null</code> if unknown.
49 * @return <code>true</code> if the thread should be granted immediate access,
50 * and <code>false</code> if it should wait for the lock to be available
51 */
52 public bool aboutToWait(Thread lockOwner) {
53 return false;
54 }
55
56 /**
57 * Notification that a thread is about to release a lock.
58 * <p>
59 * This default implementation does nothing. Subclasses may override.
60 */
61 public void aboutToRelease() {
62 //do nothing
63 }
64
65 /**
66 * Returns whether this thread currently owns any locks
67 * @return <code>true</code> if this thread owns any locks, and
68 * <code>false</code> otherwise.
69 */
70 protected final bool isLockOwnerThread() {
71 return manager.isLockOwner();
72 }
73 }