PullDataWithTimeLimitAppMain.java

import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;
import java.util.stream.IntStream;

/**
 * @author 臧萌
 */
public class PullDataWithTimeLimitAppMain {
  public static void main(String[] args) throws InterruptedException {

    long start = System.currentTimeMillis();
    CountDownLatch countDownLatch = new CountDownLatch(1);

    PullDataTask task = new PullDataTask(countDownLatch);
    new Thread(task).start();


    System.out.println("Waiting for data pulling");

    countDownLatch.await(10, TimeUnit.SECONDS);

    System.out.println("Finished waiting. Actually waited for " + (System.currentTimeMillis() - start) / 1000 + " sec. Data got from data puller is " + task.getDataList());
  }

}

class PullDataTask implements Runnable {
  private List<Integer> dataList = new ArrayList<>();

  private CountDownLatch countDownLatch;

  public PullDataTask(CountDownLatch countDownLatch) {
    this.countDownLatch = countDownLatch;
  }


  @Override
  public void run() {
    int timeSec = (int) (Math.random() * 20);

    System.out.println("going to pulling data for " + timeSec + " seconds");

    IntStream.range(0, timeSec).forEach(i -> {
      try {
        Thread.sleep(TimeUnit.SECONDS.toMillis(1));
      } catch (InterruptedException e) {
        e.printStackTrace();
      }
      dataList.add(i);
    });
    countDownLatch.countDown();

    System.out.println("pulling finished");
  }

  public List<Integer> getDataList() {
    return dataList;
  }
}