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Start your free trialmelissa zhang
760 Pointswhere to find out the correct answer?
I couldn't find out which part code is wrong. Could you please help? Do you know anywhere I can check the correct answer. many thanks
public class Order {
private String itemName;
private int priceInCents;
private String discountCode;
public Order(String itemName, int priceInCents) {
this.itemName = itemName;
this.priceInCents = priceInCents;
}
public String getItemName() {
return itemName;
}
public int getPriceInCents() {
return priceInCents;
}
public String getDiscountCode() {
return discountCode;
}
private String normalizeDiscountCode(){
return discountCode.toUpperCase();
}
public void applyDiscountCode(String discountCode) {
this.discountCode =discountCode.normalizeDiscountCode();
}
}
public class Example {
public static void main(String[] args) {
// This is here just for example use cases.
Order order = new Order(
"Yoda PEZ Dispenser",
600);
// These are valid. They are letters and the $ character only
order.applyDiscountCode("abc");
order.getDiscountCode(); // ABC
order.applyDiscountCode("$ale");
order.getDiscountCode(); // $ALE
try {
// This will throw an exception because it contains numbers
order.applyDiscountCode("ABC123");
} catch (IllegalArgumentException iae) {
System.out.println(iae.getMessage()); // Prints "Invalid discount code"
}
try {
// This will throw as well, because it contains a symbol.
order.applyDiscountCode("w@w");
}catch (IllegalArgumentException iae) {
System.out.println(iae.getMessage()); // Prints "Invalid discount code"
}
}
}
2 Answers
Melodie 1
3,931 PointsThis private String normalizeDiscountCode(){ return discountCode.toUpperCase(); }
is missing a paramater of type String , it's supposed to look like this :
private String normalizeDiscountCode(String discountCode){ return discountCode.toUpperCase(); }
and here : public void applyDiscountCode(String discountCode) { this.discountCode =discountCode.normalizeDiscountCode(); } you need to pass in the discountCode as an argument to normalizeDiscountCode() , so it should look like this :
public void applyDiscountCode(String discountCode){ this.discountCode = discountCode.normalizeDiscountCode(discountCode); }
Melodie 1
3,931 PointsThere is no general rule to that , with time you'll know when you need a parameter and when not, but each time you see an instruction that says " a method x takes something " , that means this method needs a parameter.
melissa zhang
760 PointsThanks a lot.
melissa zhang
760 PointsSorry to bothering you again. I just changed the code as you taught me. But it still shows wrong. Could you please check my new code ? I have just posted another question. I don't know if you can see it. Many thanks.
melissa zhang
760 PointsI find out what is wrong now. thank you very much.
melissa zhang
760 Pointsmelissa zhang
760 PointsThank you so much. You are a star.
melissa zhang
760 Pointsmelissa zhang
760 PointsIt seems very confusing that sometimes it needs a parameter in the method sometimes not. Do you know why and when it needs parameter? Thank you.