ActorRef bank = _system.actorOf(new Props(BankActor.class));
bank.tell(new AccountDebit(Float.parseFloat("1000")));
bank.tell(new AccountCredit(Float.parseFloat("1000")));
bank.tell(new AccountDebit(Float.parseFloat("1000")));
bank.tell(new AccountDebit(Float.parseFloat("1000")));
bank.tell(new AccountDebit(Float.parseFloat("3500")));
bank.tell(new AccountCredit(Float.parseFloat("2500")));
bank.tell(new AccountDebit(Float.parseFloat("3500")));
// sleeping to allow some time for all messages to be processed