PaymentGateway { public boolean charge(int amount, String customerName, int cardNumber) { logger.log(Level.INFO, "Charged " + customerName + " EUR " + amount + " on card: " + cardNumber); return true; }  boolean charge(int amount, String customerName, int cardNumber);  }
@Test public void testCharge() throws Exception { PaymentGateway paymentGateway = new PaymentGateway(); assertTrue(paymentGateway.charge(20,"OOSE", 1234)); }