Waiting for the Finalization of a Thread

DataSourcesLoader.java

import java.util.Date;
import java.util.concurrent.TimeUnit;

public class DataSourcesLoader implements Runnable {

   @Override
   public void run() {
      
      // Writes a messsage
      System.out.printf("Begining data sources loading: %s\n",new Date());
      // Sleeps four seconds
      try {
         TimeUnit.SECONDS.sleep(4);
      } catch (InterruptedException e) {
         e.printStackTrace();
      }
      // Writes a message
      System.out.printf("Data sources loading has finished: %s\n",new Date());
   }
}

Main.java

// Waiting for the finalization of a thread

import java.util.Date;

public class Main {

   public static void main(String[] args) {

      // Creates and starts a DataSourceLoader runnable object
      DataSourcesLoader dsLoader = new DataSourcesLoader();
      Thread thread1 = new Thread(dsLoader,"DataSourceThread");

      // Creates and starts a NetworkConnectionsLoader runnable object
      NetworkConnectionsLoader ncLoader = new NetworkConnectionsLoader();
      Thread thread2 = new Thread(ncLoader,"NetworkConnectionLoader");

      // Start both threads
      thread1.start();
      thread2.start();

      // Wait for the finalization of the two threads
      try {
         thread1.join();
         thread2.join();
      } catch (InterruptedException e) {
         e.printStackTrace();
      }

      // Waits a message
      System.out.printf("Main: Configuration has been loaded: %s\n",new Date());
   }
}

NetworkConnectionsLoader.java

import java.util.Date;
import java.util.concurrent.TimeUnit;

public class NetworkConnectionsLoader implements Runnable {

   @Override
   public void run() {
      // Writes a message
      System.out.printf("Begining network connections loading: %s\n",new Date());
      // Sleep six seconds
      try {
         TimeUnit.SECONDS.sleep(6);
      } catch (InterruptedException e) {
         e.printStackTrace();
      }
      // Writes a message
      System.out.printf("Network connections loading has finished: %s\n",new Date());
   }
}