/*
* Mojito Distributed Hash Table (Mojito DHT)
* Copyright (C) 2006-2007 LimeWire LLC
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
package org.limewire.mojito.concurrent;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutionException;
/**
* A CallableDHTTask takes a DHTTask, starts it and waits for
* the result.
*/
public class CallableDHTTask<T> implements Callable<T> {
private final DHTValueFuture<T> future = new DHTValueFuture<T>();
private final DHTTask<T> task;
private boolean started = false;
public CallableDHTTask(DHTTask<T> task) {
this.task = task;
}
public T call() throws InterruptedException, ExecutionException {
synchronized (future) {
if (!started) {
task.start(future);
started = true;
}
return future.get();
}
}
}