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Start your free trialSahil Chawla
5,834 PointsIncorrect Code Snippet ?
I think my code is correct but still getting below error:
Bummer! Hmmm...I ran order.applyDiscountCode("h1!") and I expected it to throw an IllegalArgumentException, but it didn't
Can someone let me know what I am doing wrong ?
Regards, Sahil
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;
}
public void applyDiscountCode(String discountCode) {
this.discountCode = discountCode;
try{
this.discountCode = normalizeDiscountCode(discountCode);
} catch (IllegalArgumentException iae){
System.out.println(iae.getMessage());
}
}
private String normalizeDiscountCode(String discountCode){
this.discountCode = discountCode.toUpperCase();
for(char c: this.discountCode.toCharArray()) {
if (!Character.isLetter(c) && c != '$' ) {
throw new IllegalArgumentException("Invalid discount code");
}
}
return this.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(); // $ALE
try {
// This will throw an exception because it contains numbers
order.applyDiscountCode("ABC123");
} catch (IllegalArgumentException iae) {
System.out.println(iae.getMessage()); // Prints "Invalid discount code"
}
try {
// This will throw as well, because it contains a symbol.
order.applyDiscountCode("w@w");
}catch (IllegalArgumentException iae) {
System.out.println(iae.getMessage()); // Prints "Invalid discount code"
}
}
}
1 Answer
Richard Lambert
Courses Plus Student 7,180 PointsHello mate,
- Remove every instance of the keyword
this
found withinnormalizeDiscountCode(String discountCode)
. In this context,this.discountCode
refers to the member variable with that name and not the method parameter with the same name, resulting in a logical error. - Whilst it's possible to re-assign to the method parameter
discountCode
, having calledtoUpperCase()
on it, have you considered just callingdiscountCode.toUpperCase()
as part of your return statement? -
IllegalArgumentException
is an example of what is known as an unchecked exception. Catching it inapplyDiscountCode(String discountCode)
isn't incorrect, but just know that you don't have to, nor do you have to declare that your method throws such an exception if it isn't handled.
public void applyDiscountCode(String discountCode) {
this.discountCode = discountCode;
try { // (3)
this.discountCode = normalizeDiscountCode(discountCode);
} catch (IllegalArgumentException iae){
System.out.println(iae.getMessage());
}
}
private String normalizeDiscountCode(String discountCode){
this.discountCode = discountCode.toUpperCase(); // (1)(2)
for(char c: this.discountCode.toCharArray()) { // (1)
if (!Character.isLetter(c) && c != '$' ) {
throw new IllegalArgumentException("Invalid discount code");
}
}
return this.discountCode; // (1)(2)
}
Hope this helps
Sahil Chawla
5,834 PointsSahil Chawla
5,834 PointsThanks for replying Richard. :) I removed try and catch block from applyDiscountCode() method and it worked :)