Ex. 18.4 Define an interface specification for the Currency Converter and Check credit rating services shown in Figure 18.7.
Currency Converter Interface
Inputs: Currency type, Amount of Currency, currency to be converted to.
Operations: getExchangeRate(), convert(currency1, currency2),
Outputs: currencyContversion
Exceptions: Invalid Currency, Invalid Amount
Check Credit Rating Interface
Inputs: SSN, DateOfBirth
Operations: getCreditScore(SSN, DateOfBirth)
Outputs: creditScore
Exceptions: invalidSSN, invalidDoB