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Start your free trialRizwan Renesa
7,805 PointsWhat am I doing wrong?
in the normalizeDiscountCode method, if I have return this.discountCode.toUpperCase(); I get a Java Null Pointer exception?
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(String discountCode){
return this.discountCode.toUpperCase();
}
public void applyDiscountCode(String discountCode) {
this.discountCode = normalizeDiscountCode(discountCode);
}
}
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"
}
}
}
1 Answer
Gabe Olesen
1,606 PointsHey Rizwan,
You're close, see below;
public void applyDiscountCode(String discountCode) {
this.discountCode = normalizeDiscountCode (discountCode);
}
private String normalizeDiscountCode(String discountCode) {
return this.discountCode = discountCode.toUpperCase();
}
}
Your code:
private String normalizeDiscountCode(String discountCode){
return this.discountCode.toUpperCase();
}
You would need to do
return this.discountCode = discountCode.toUpperCase();
This means it will return whatever the user inputted (abc) <- argument and return it as (ABC).
Hope this helps!