| /* |
| * Copyright (c) 2009-2010 jMonkeyEngine |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions are |
| * met: |
| * |
| * * Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * |
| * * Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * |
| * * Neither the name of 'jMonkeyEngine' nor the names of its contributors |
| * may be used to endorse or promote products derived from this software |
| * without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED |
| * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR |
| * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
| * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
| * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
| * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF |
| * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING |
| * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS |
| * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| package com.jme3.app; |
| |
| import java.util.concurrent.*; |
| import java.util.concurrent.locks.Condition; |
| import java.util.concurrent.locks.ReentrantLock; |
| import java.util.logging.Level; |
| import java.util.logging.Logger; |
| |
| /** |
| * <code>AppTask</code> is used in <code>AppTaskQueue</code> to manage tasks that have |
| * yet to be accomplished. The AppTask system is used to execute tasks either |
| * in the OpenGL/Render thread, or outside of it. |
| * |
| * @author Matthew D. Hicks, lazloh |
| */ |
| public class AppTask<V> implements Future<V> { |
| private static final Logger logger = Logger.getLogger(AppTask.class |
| .getName()); |
| |
| private final Callable<V> callable; |
| |
| private V result; |
| private ExecutionException exception; |
| private boolean cancelled, finished; |
| private final ReentrantLock stateLock = new ReentrantLock(); |
| private final Condition finishedCondition = stateLock.newCondition(); |
| |
| /** |
| * Create an <code>AppTask</code> that will execute the given |
| * {@link Callable}. |
| * |
| * @param callable The callable to be executed |
| */ |
| public AppTask(Callable<V> callable) { |
| this.callable = callable; |
| } |
| |
| public boolean cancel(boolean mayInterruptIfRunning) { |
| stateLock.lock(); |
| try { |
| if (result != null) { |
| return false; |
| } |
| cancelled = true; |
| |
| finishedCondition.signalAll(); |
| |
| return true; |
| } finally { |
| stateLock.unlock(); |
| } |
| } |
| |
| public V get() throws InterruptedException, ExecutionException { |
| stateLock.lock(); |
| try { |
| while (!isDone()) { |
| finishedCondition.await(); |
| } |
| if (exception != null) { |
| throw exception; |
| } |
| return result; |
| } finally { |
| stateLock.unlock(); |
| } |
| } |
| |
| public V get(long timeout, TimeUnit unit) throws InterruptedException, ExecutionException, TimeoutException { |
| stateLock.lock(); |
| try { |
| if (!isDone()) { |
| finishedCondition.await(timeout, unit); |
| } |
| if (exception != null) { |
| throw exception; |
| } |
| if (result == null) { |
| throw new TimeoutException("Object not returned in time allocated."); |
| } |
| return result; |
| } finally { |
| stateLock.unlock(); |
| } |
| } |
| |
| public boolean isCancelled() { |
| stateLock.lock(); |
| try { |
| return cancelled; |
| } finally { |
| stateLock.unlock(); |
| } |
| } |
| |
| public boolean isDone() { |
| stateLock.lock(); |
| try { |
| return finished || cancelled || (exception != null); |
| } finally { |
| stateLock.unlock(); |
| } |
| } |
| |
| public Callable<V> getCallable() { |
| return callable; |
| } |
| |
| public void invoke() { |
| try { |
| final V tmpResult = callable.call(); |
| |
| stateLock.lock(); |
| try { |
| result = tmpResult; |
| finished = true; |
| |
| finishedCondition.signalAll(); |
| } finally { |
| stateLock.unlock(); |
| } |
| } catch (Exception e) { |
| logger.logp(Level.SEVERE, this.getClass().toString(), "invoke()", "Exception", e); |
| |
| stateLock.lock(); |
| try { |
| exception = new ExecutionException(e); |
| |
| finishedCondition.signalAll(); |
| } finally { |
| stateLock.unlock(); |
| } |
| } |
| } |
| |
| } |