CompletionService Test

CompletionServiceTest.java

package org.nkcoder.module.javatest.concurrent;

import java.util.concurrent.*;

/**
 * Created by nkcoder on 12/21/16.
 */
public class CompletionServiceTest {

    public static void main(String[] args) {
        Executor executor = Executors.newFixedThreadPool(3);
        CompletionService completionService = new ExecutorCompletionService(executor);
        int size = 10;
        for (int i = 0; i < size; i++) {
            final int raw = i;
            final int multiple = Math.multiplyExact(raw, raw);
            completionService.submit(() -> {
                System.out.println("raw = " + raw);
                try {
                    TimeUnit.MILLISECONDS.sleep(multiple);
                } catch (InterruptedException e) {
                    Thread.currentThread().interrupt();
                }
                return multiple;
            });
        }

        for (int i = 0; i < size; i++) {
            try {
                Future future = completionService.take();
                System.out.println("multiple: " + future.get());
            } catch (InterruptedException | ExecutionException e) {
                Thread.currentThread().interrupt();
            }
        }

        System.out.println("done.");
    }
}