private static ExecutorService getCachedPool(ThreadFactory threadFactory)
{
    return new ThreadPoolExecutor(20, 20,
            60L, TimeUnit.SECONDS,
            new SynchronousQueue<Runnable>(),
            threadFactory);
}

List<Future<ArtistCoverImage>> results = ArtistArtworkOnlineLookup.getExecutorService()
    .invokeAll(lookups);

private static ExecutorService getCachedPool(ThreadFactory threadFactory)
    {
        return new ThreadPoolExecutor(20, Integer.MAX,
                60L, TimeUnit.SECONDS,
                new SynchronousQueue<Runnable>(),
                threadFactory);
    }