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Atul Varma
4,285 Pointswhat's the logic ?
In the normalizeDiscountCode verify that only letters or the $ character are used. If any other character is used, throw a IllegalArgumentException with the message Invalid discount code.
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;
}
private String normalizeDiscountCode(String discountCode){
if(!discountCode.matches("[a-zA-Z]+")|| !discountCode.matches('$'){
throw new IllegalArgumentException("Invalid Discount Code");
}
discountCode = discountCode.toUpperCase();
return discountCode;
}
public int getPriceInCents() {
return priceInCents;
}
public String getDiscountCode() {
return discountCode;
}
public void applyDiscountCode(String discountCode) {
discountCode = normalizeDiscountCode(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(); // $ALE
try {
// This will throw an exception because it contains numbers
order.applyDiscountCode("ABC123");
} catch (IllegalArgumentException iae) {
System.out.println(iae.getMessage()); // Prints "Invalid discount code"
}
try {
// This will throw as well, because it contains a symbol.
order.applyDiscountCode("w@w");
}catch (IllegalArgumentException iae) {
System.out.println(iae.getMessage()); // Prints "Invalid discount code"
}
}
}
2 Answers
Thomas Nilsen
14,957 PointsTry this instead;
private String normalizeDiscountCode(String discountCode){
//Loop through the passed in String
for(char c : discountCode.toCharArray()) {
//For each letter, we check if the
//character is NOT a letter, and at the same time is not
//a dollar-sign either - we throw an exception
if(!Character.isLetter(c) && c != '$') {
throw new IllegalArgumentException("invalid discount code.");
}
}
//return the valid code
return discountCode.toUpperCase();
}
Atul Varma
4,285 PointsThank you Thomas Nilsen.