[Ch15] Starting example code for shutting down the pools

package ch15;

import java.util.List;

import java.util.concurrent.ExecutorService;

import java.util.concurrent.Executors;

import java.util.concurrent.TimeUnit;

public class ClosingTime {

  public static void main(String[] args) {

    forceShutdown();

  }

  static void shutdownGracefully() {

    ExecutorService threadPool = Executors.newFixedThreadPool(2);

    threadPool.execute(() -> longJob("Long Job 1"));

    threadPool.execute(() -> shortJob("Short Job"));

    threadPool.execute(() -> shortJob("Long Job 2"));

    threadPool.execute(() -> shortJob("Shouldn't start job"));

    threadPool.shutdown();

    try {

      System.out.println("Finished? " + threadPool.awaitTermination(1, TimeUnit.SECONDS));

    } catch (InterruptedException e) {

      e.printStackTrace();

    }

  }

  static void forceShutdown() {

    ExecutorService threadPool = Executors.newFixedThreadPool(2);

    threadPool.execute(() -> longJob("Long Job 1"));

    threadPool.execute(() -> shortJob("Short Job"));

    threadPool.execute(() -> longJob("Long Job 2"));

    threadPool.execute(() -> shortJob("Shouldn't start job"));

    List<Runnable> unfinished = threadPool.shutdownNow();

    System.out.println("unfinished.size() = " + unfinished.size());

    for (Runnable runnable : unfinished) {

      System.out.println(runnable);

    }

//    try {

//      System.out.println("Finished? " + threadPool.awaitTermination(1, TimeUnit.SECONDS));

//    } catch (InterruptedException e) {

//      e.printStackTrace();

//    }

  }

  private static void longJob(String jobName) {

    // use sleep() to pretend like this is a long-running job

    try {

      TimeUnit.SECONDS.sleep(3);

      System.out.println(jobName);

    } catch (InterruptedException e) {

      e.printStackTrace();

    }

  }

  private static void shortJob(String jobName) {

    System.out.println(jobName);

  }

  class ShortJob implements Runnable {

    private String jobName;

    ShortJob(String jobName) {

      this.jobName = jobName;

    }

    public void run() {

      System.out.println(jobName);

    }

  }

  class LongJob implements Runnable {

    private String jobName;

    LongJob(String jobName) {

      this.jobName = jobName;

    }

    public void run() {

      try {

        TimeUnit.SECONDS.sleep(3);

        System.out.println(jobName);

      } catch (InterruptedException e) {

        e.printStackTrace();

      }

    }

  }

}