ExchangerDemo.java

Exchanger<String> exchanger = new Exchanger<>(); 
Runnable laila = () -> {
   try {
      String messageFromMajnu = exchanger.exchange("I miss you Majnu!");
   } catch (InterruptedException e) {
      Thread.currentThread.interrupt();
      throw new RuntimeException(e);
   }
};
 
Runnable majnu = () -> {
   try {
      String messageFromLaila = exchanger.exchange("I miss you too Laila");
   } catch (InterruptedException e) {
      Thread.currentThread.interrupt();
      throw new RuntimeException(e);
   }
};