| 1 | // Copyright 2004-2007 Jean-Francois Poilpret |
| 2 | // |
| 3 | // Licensed under the Apache License, Version 2.0 (the "License"); |
| 4 | // you may not use this file except in compliance with the License. |
| 5 | // You may obtain a copy of the License at |
| 6 | // |
| 7 | // http://www.apache.org/licenses/LICENSE-2.0 |
| 8 | // |
| 9 | // Unless required by applicable law or agreed to in writing, software |
| 10 | // distributed under the License is distributed on an "AS IS" BASIS, |
| 11 | // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 12 | // See the License for the specific language governing permissions and |
| 13 | // limitations under the License. |
| 14 | |
| 15 | // Original copyright is held by Nathan Arthur |
| 16 | // [Java Specialists' Newsletter, Issue #75, 2003-07-29] |
| 17 | |
| 18 | package net.sourceforge.hivegui.autowait; |
| 19 | |
| 20 | import org.apache.commons.logging.Log; |
| 21 | import org.apache.commons.logging.LogFactory; |
| 22 | |
| 23 | /** |
| 24 | * This class implements a delay timer that will call trigger() |
| 25 | * on the DelayTimerCallback delay milliseconds after |
| 26 | * startTimer() was called, if stopTimer() was not called first. |
| 27 | * The timer will only throw events after startTimer() is called. |
| 28 | * Until then, it does nothing. It is safe to call stopTimer() |
| 29 | * and startTimer() repeatedly. |
| 30 | * Note that calls to trigger() will happen on the timer thread. |
| 31 | * This class is multiple-thread safe. |
| 32 | * |
| 33 | * @author Nathan Arthur |
| 34 | */ |
| 35 | public class DelayTimer extends Thread |
| 36 | { |
| 37 | static final private Log _logger = LogFactory.getLog(DelayTimer.class); |
| 38 | |
| 39 | public DelayTimer(DelayTimerCallback callback, long delay) |
| 40 | { |
| 41 | _callback = callback; |
| 42 | _delay = delay; |
| 43 | setDaemon(true); |
| 44 | start(); |
| 45 | } |
| 46 | |
| 47 | /** |
| 48 | * Calling this method twice will reset the timer. |
| 49 | */ |
| 50 | public void startTimer() |
| 51 | { |
| 52 | synchronized (_mutex) |
| 53 | { |
| 54 | _waitTime = _delay; |
| 55 | _mutex.notify(); |
| 56 | } |
| 57 | } |
| 58 | |
| 59 | public void stopTimer() |
| 60 | { |
| 61 | try |
| 62 | { |
| 63 | synchronized (_mutex) |
| 64 | { |
| 65 | synchronized (_triggeredMutex) |
| 66 | { |
| 67 | if (_triggered) |
| 68 | { |
| 69 | _triggeredMutex.wait(); |
| 70 | } |
| 71 | } |
| 72 | _waitTime = 0; |
| 73 | _mutex.notify(); |
| 74 | } |
| 75 | } |
| 76 | catch (InterruptedException e) |
| 77 | { |
| 78 | _logger.error("stopTimer()", e); |
| 79 | } |
| 80 | } |
| 81 | |
| 82 | @Override public void run() |
| 83 | { |
| 84 | try |
| 85 | { |
| 86 | while (!_quit) |
| 87 | { |
| 88 | synchronized (_mutex) |
| 89 | { |
| 90 | // We rely on wait(0) being implemented to wait forever here |
| 91 | if (_waitTime < 0) |
| 92 | { |
| 93 | _triggered = true; |
| 94 | _waitTime = 0; |
| 95 | } |
| 96 | else |
| 97 | { |
| 98 | long saveWaitTime = _waitTime; |
| 99 | _waitTime = -1; |
| 100 | _mutex.wait(saveWaitTime); |
| 101 | } |
| 102 | } |
| 103 | //CSOFF: IllegalCatchCheck |
| 104 | try |
| 105 | { |
| 106 | if (_triggered) |
| 107 | { |
| 108 | _callback.trigger(); |
| 109 | } |
| 110 | } |
| 111 | catch (RuntimeException e) |
| 112 | { |
| 113 | _logger.warn("run()", e); |
| 114 | } |
| 115 | finally |
| 116 | { |
| 117 | synchronized (_triggeredMutex) |
| 118 | { |
| 119 | _triggered = false; |
| 120 | _triggeredMutex.notify(); |
| 121 | } |
| 122 | } |
| 123 | //CSON: IllegalCatchCheck |
| 124 | } |
| 125 | } |
| 126 | catch (InterruptedException e) |
| 127 | { |
| 128 | _logger.error("run()", e); |
| 129 | } |
| 130 | } |
| 131 | |
| 132 | public void quit() |
| 133 | { |
| 134 | synchronized (_mutex) |
| 135 | { |
| 136 | _quit = true; |
| 137 | _mutex.notify(); |
| 138 | } |
| 139 | } |
| 140 | |
| 141 | private final DelayTimerCallback _callback; |
| 142 | private final Object _mutex = new Object(); |
| 143 | private final Object _triggeredMutex = new Object(); |
| 144 | private final long _delay; |
| 145 | private boolean _quit; |
| 146 | private boolean _triggered; |
| 147 | private long _waitTime; |
| 148 | } |