FXServiceMockTest.java

@Test
    public void transfer_sgd_to_inr() {

        FXService fxService = new FXService(currencyConverter, bankService, 0.0d);
        BankAccount account = new BankAccount("1111-22222", "SuperStableBank");

        expect(currencyConverter.convert(1, "SGD", "INR")).andReturn(50d);
        expect(bankService.deposit(100d, account)).andReturn("99999");
        replay(currencyConverter, bankService);

        String id = fxService.transfer(new Money(SGD, 2d), account, INR);
        assertEquals("99999", id);

        verify(currencyConverter, bankService);
    }