Mercurial > hg > graal-compiler
comparison agent/src/share/classes/sun/jvm/hotspot/utilities/MessageQueueBackend.java @ 0:a61af66fc99e jdk7-b24
Initial load
author | duke |
---|---|
date | Sat, 01 Dec 2007 00:00:00 +0000 |
parents | |
children | c18cbe5936b8 |
comparison
equal
deleted
inserted
replaced
-1:000000000000 | 0:a61af66fc99e |
---|---|
1 /* | |
2 * Copyright 2000 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, | |
20 * CA 95054 USA or visit www.sun.com if you need additional information or | |
21 * have any questions. | |
22 * | |
23 */ | |
24 | |
25 package sun.jvm.hotspot.utilities; | |
26 | |
27 /** The backend for the message queue abstraction. This class is | |
28 instantiated first and queried to provide the two "sides" of the | |
29 message queue. */ | |
30 | |
31 import java.util.LinkedList; | |
32 | |
33 public class MessageQueueBackend { | |
34 // The two queues | |
35 private MessageQueueImpl leftRightQueue; | |
36 private MessageQueueImpl rightLeftQueue; | |
37 | |
38 public MessageQueueBackend() { | |
39 LinkedList leftRightPipe = new LinkedList(); | |
40 LinkedList rightLeftPipe = new LinkedList(); | |
41 leftRightQueue = new MessageQueueImpl(rightLeftPipe, leftRightPipe); | |
42 rightLeftQueue = new MessageQueueImpl(leftRightPipe, rightLeftPipe); | |
43 } | |
44 | |
45 /** Get one of the two symmetric sides of this message queue. */ | |
46 public MessageQueue getFirstQueue() { | |
47 return leftRightQueue; | |
48 } | |
49 | |
50 /** Get second of the two symmetric sides of this message queue. */ | |
51 public MessageQueue getSecondQueue() { | |
52 return rightLeftQueue; | |
53 } | |
54 | |
55 private class MessageQueueImpl implements MessageQueue { | |
56 private LinkedList readList; | |
57 private LinkedList writeList; | |
58 | |
59 public MessageQueueImpl(LinkedList listToReadFrom, LinkedList listToWriteTo) { | |
60 readList = listToReadFrom; | |
61 writeList = listToWriteTo; | |
62 } | |
63 | |
64 public Object readMessage() { | |
65 synchronized(readList) { | |
66 while (readList.isEmpty()) { | |
67 try { | |
68 readList.wait(); | |
69 } | |
70 catch (InterruptedException e) { | |
71 } | |
72 } | |
73 return readList.removeFirst(); | |
74 } | |
75 } | |
76 | |
77 public Object readMessageWithTimeout(long millis) { | |
78 synchronized(readList) { | |
79 if (readList.isEmpty()) { | |
80 if (millis == 0) { | |
81 return null; | |
82 } | |
83 try { | |
84 readList.wait(millis); | |
85 } | |
86 catch (InterruptedException e) { | |
87 } | |
88 } | |
89 // If list is still empty after wait, return null | |
90 if (readList.isEmpty()) { | |
91 return null; | |
92 } | |
93 return readList.removeFirst(); | |
94 } | |
95 } | |
96 | |
97 public void writeMessage(Object obj) { | |
98 synchronized(writeList) { | |
99 writeList.addLast(obj); | |
100 writeList.notify(); | |
101 } | |
102 } | |
103 } | |
104 } |