import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.Executor;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.LinkedBlockingQueue;
import java.util.concurrent.ThreadFactory;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.regex.Matcher;

            // be exhausted
            //
            return new ThreadPoolExecutor(
                    parallelism, Integer.MAX_VALUE, 0L, TimeUnit.MILLISECONDS, new LinkedBlockingQueue<>()) {
                final AtomicInteger parked = new AtomicInteger();

                @Override
                public <T> List<Future<T>> invokeAll(Collection<? extends Callable<T>> tasks)