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copied!<p>How about:</p> <p>Submit your <code>Callable</code> to the <code>ExecutorService</code> and keep a handle to the returned <code>Future</code>.</p> <pre><code>ExecutorService executorService = ... // Create ExecutorService. Callable<Result> callable = new MyCallable(); // Create work to be done. Future<Result> fut = executorService.submit(callable); </code></pre> <p>Wrap the <code>Future</code> in an implementation of <code>Delayed</code> whereby <code>Delayed</code>'s <code>getDelay(TimeUnit)</code> method returns the maximum execution time for the work in question.</p> <pre><code>public class DelayedImpl<T> implements Delayed { private final long maxExecTimeMillis; private final Future<T> future; public DelayedImpl(long maxExecTimeMillis, Future<T> future) { this.maxExecMillis = maxExecMillis; this.future = future; } public TimeUnit getDelay(TimeUnit timeUnit) { return timeUnit.convert(maxExecTimeMillis, TimeUnit.MILLISECONDS); } public Future<T> getFuture() { return future; } } DelayedImpl impl = new DelayedImpl(3000L, fut); // Max exec. time == 3000ms. Add the `DelayedImpl` to a `DelayQueue`. Queue<DelayedImpl> queue = new DelayQueue<DelayImpl>(); queue.add(impl); </code></pre> <p>Have a thread repeatedly <code>take()</code> from the queue and check whether each <code>DelayedImpl</code>'s <code>Future</code> is complete by calling <code>isDone()</code>; If not then cancel the task.</p> <pre><code>new Thread(new Runnable() { public void run() { while (!Thread.interrupted) { DelayedImpl impl = queue.take(); // Perform blocking take. if (!impl.getFuture().isDone()) { impl.getFuture().cancel(true); } } } }).start(); </code></pre> <p>The main advantage to this approach is that you can set a <strong>different maximum execution time per task</strong> and the delay queue will automatically return the task with the smallest amount of execution time remaining.</p>

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