Java Tutorial/Thread/ExecutorService

Create ExecutorService to manage threads

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
public class MainClass {
  public static void main(String[] args) {
    PrintTask task1 = new PrintTask("thread1");
    PrintTask task2 = new PrintTask("thread2");
    PrintTask task3 = new PrintTask("thread3");
    System.out.println("Starting threads");
    ExecutorService threadExecutor = Executors.newCachedThreadPool();
    // start threads and place in runnable state
    threadExecutor.execute(task1); // start task1
    threadExecutor.execute(task2); // start task2
    threadExecutor.execute(task3); // start task3
    threadExecutor.shutdown(); // shutdown worker threads
    System.out.println("Threads started, main ends\n");
  }
}
class PrintTask implements Runnable {
  private int sleepTime;
  private String threadName;
  public PrintTask(String name) {
    threadName = name;
    sleepTime = 1000;
  }
  public void run() {
    try {
      System.out.printf("%s going to sleep for %d milliseconds.\n", threadName, sleepTime);
      Thread.sleep(sleepTime); // put thread to sleep
    } catch (InterruptedException exception) {
      exception.printStackTrace();
    }
    System.out.printf("%s done sleeping\n", threadName);
  }
}

Starting threads
thread1 going to sleep for 1000 milliseconds.
thread3 going to sleep for 1000 milliseconds.
thread2 going to sleep for 1000 milliseconds.
Threads started, main ends
thread1 done sleeping
thread3 done sleeping
thread2 done sleeping