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Start your free trialOlha Markova
2,050 PointsProblem with a normalize method
I am working at the challenge "Applying a Discount Code" and get an error message, when I am trying to use normilize method
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){
this.discountCode = normalizeDiscountCode (discountCode);
return (discountCode.toUpperCase());
}
public void applyDiscountCode(String discountCode) {
this.discountCode = 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
Simon Coates
28,694 PointsYou have most of the right bits of code, just in the wrong places. Try
public void applyDiscountCode(String discountCode) {
this.discountCode = normalizeDiscountCode(discountCode);
}
private String normalizeDiscountCode(String discountCode){
return discountCode.toUpperCase();
}
Simon Coates
28,694 PointsSimon Coates
28,694 Pointswith your code, the following function is recursive.
If you call this method, it calls itself, which calls itself, which calls itself. Sometimes this is what you want to do, but typically only if there is a condition being applied that can stop further recursive calls. The wiki article on recursive states:
"Recursion occurs when a thing is defined in terms of itself or of its type. Recursion is used in a variety of disciplines ranging from linguistics to logic. The most common application of recursion is in mathematics and computer science, where a function being defined is applied within its own definition. While this apparently defines an infinite number of instances, it is often done in such a way that no loop or infinite chain of references can occur."