/*
* Quasar: lightweight threads and actors for the JVM.
* Copyright (C) 2013, Parallel Universe Software Co. All rights reserved.
*
* This program and the accompanying materials are dual-licensed under
* either the terms of the Eclipse Public License v1.0 as published by
* the Eclipse Foundation
*
* or (per the licensee's choosing)
*
* under the terms of the GNU Lesser General Public License version 3.0
* as published by the Free Software Foundation.
*/
package co.paralleluniverse.fibers.futures;
import co.paralleluniverse.fibers.Fiber;
import co.paralleluniverse.fibers.FiberAsync;
import co.paralleluniverse.fibers.RuntimeExecutionException;
import co.paralleluniverse.fibers.SuspendExecution;
import com.google.common.util.concurrent.ListenableFuture;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Executor;
/**
*
* @author pron
*/
public class FiberAsyncListenableFuture<V> extends FiberAsync<V, Runnable, Void, ExecutionException> {
public static <V> V get(ListenableFuture<V> future) throws ExecutionException, InterruptedException, SuspendExecution {
if (Fiber.currentFiber() != null && !future.isDone())
return new FiberAsyncListenableFuture<>(future).run();
else
return future.get();
}
public static <V> V getNoSuspend(final ListenableFuture<V> future) throws ExecutionException, InterruptedException {
if (Fiber.currentFiber() != null && !future.isDone()) {
try {
return new Fiber<V>() {
@Override
protected V run() throws SuspendExecution, InterruptedException {
try {
return new FiberAsyncListenableFuture<>(future).run();
} catch (ExecutionException e) {
throw new RuntimeExecutionException(e.getCause());
}
}
}.start().get();
} catch (ExecutionException e) {
Throwable t = e.getCause();
if (t instanceof RuntimeExecutionException)
throw new ExecutionException(t.getCause());
else
throw e;
}
} else
return future.get();
}
///////////////////////////////////////////////////////////////////////
private final ListenableFuture<V> fut;
private final Runnable listener;
private Fiber<?> fiber;
private FiberAsyncListenableFuture(ListenableFuture<V> future) {
this.fut = future;
this.listener = new Runnable() {
@Override
public void run() {
try {
assert fut.isDone();
final V res = fut.get();
completed(res, fiber);
} catch (ExecutionException e) {
failed(e, fiber);
} catch (InterruptedException e) {
throw new AssertionError(); // can't happen b/c we know future is done.
}
}
};
}
@Override
protected Runnable getCallback() {
return listener;
}
@Override
protected Void requestAsync(Fiber current, Runnable callback) {
this.fiber = current;
fut.addListener(listener, sameThreadExecutor);
return null;
}
private static final Executor sameThreadExecutor = new Executor() {
@Override
public void execute(Runnable command) {
command.run();
}
};
}