| /* |
| * Copyright 2000-2012 JetBrains s.r.o. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.jetbrains.jps.api; |
| |
| import java.util.concurrent.*; |
| import java.util.concurrent.atomic.AtomicBoolean; |
| |
| /** |
| * @author Eugene Zhuravlev |
| * Date: 5/3/12 |
| */ |
| public class BasicFuture<T> implements Future<T> { |
| protected final Semaphore mySemaphore = new Semaphore(1); |
| private final AtomicBoolean myDone = new AtomicBoolean(false); |
| private final AtomicBoolean myCanceledState = new AtomicBoolean(false); |
| |
| public BasicFuture() { |
| mySemaphore.acquireUninterruptibly(); |
| } |
| |
| public void setDone() { |
| if (!myDone.getAndSet(true)) { |
| mySemaphore.release(); |
| } |
| } |
| |
| public boolean cancel(boolean mayInterruptIfRunning) { |
| if (isDone()) { |
| return false; |
| } |
| if (!myCanceledState.getAndSet(true)) { |
| try { |
| performCancel(); |
| } |
| catch (Exception e) { |
| throw new RuntimeException(e); |
| } |
| } |
| return true; |
| } |
| |
| protected void performCancel() throws Exception { |
| } |
| |
| public boolean isCancelled() { |
| return myCanceledState.get(); |
| } |
| |
| public boolean isDone() { |
| return myDone.get(); |
| } |
| |
| public void waitFor() { |
| try { |
| while (!isDone()) { |
| if (mySemaphore.tryAcquire(100L, TimeUnit.MILLISECONDS)) { |
| mySemaphore.release(); |
| } |
| } |
| } |
| catch (InterruptedException ignored) { |
| } |
| } |
| |
| public boolean waitFor(long timeout, TimeUnit unit) { |
| try { |
| if (!isDone()) { |
| if (mySemaphore.tryAcquire(timeout, unit)) { |
| mySemaphore.release(); |
| } |
| } |
| } |
| catch (InterruptedException ignored) { |
| } |
| return isDone(); |
| } |
| |
| public T get() throws InterruptedException, ExecutionException { |
| waitFor(); |
| return null; |
| } |
| |
| public T get(long timeout, TimeUnit unit) throws InterruptedException, ExecutionException, TimeoutException { |
| if (!waitFor(timeout, unit)) { |
| throw new TimeoutException(); |
| } |
| return null; |
| } |
| } |