class Amigo

import java.util.concurrent.CyclicBarrier;

public class Amigo extends Thread {

      private final String name;

      private final CyclicBarrier barrier;

      public Amigo(String name, CyclicBarrier barrier) {

            this.name = name;

            this.barrier = barrier;

      }

      public void run() {

            while (true) {

                  try {

                        sleep((int) (10000 * Math.random()));

                        System.out.println(name + " esperando ...");

                        barrier.await();

                  } catch (Exception e) {

                        e.printStackTrace();

                  }

            }

      }

}    

class Amigos

import java.util.Date;

import java.util.concurrent.CyclicBarrier;

public class Amigos {

      public static void main(String[] args) {

            Escucha escucha = new Escucha();

            CyclicBarrier cita = new CyclicBarrier(3, escucha);

            Amigo pedro = new Amigo("Pedro", cita);

            Amigo angel = new Amigo("Angel", cita);

            Amigo bruno = new Amigo("Bruno", cita);

            pedro.start();

            angel.start();

            bruno.start();

      }

      private static class Escucha implements Runnable {

            public void run() {

                  System.out.println(new Date());

            }

      }

}