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Java Java Objects Delivering the MVP Applying a Discount Code

Task 1 is no longer passing

i dont understand what im doing wrong

Order.java
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 void applyDiscountCode(String discountCode) {
    this.discountCode = normalizeDiscountCode(discountCode);

  }
  private String normalizeDiscountCode(String discountCode) {

    for(int i = 0; i<discountCode.length() ;i++){
    char letter = discountCode.charAt(i); 
   if(!Character.isLetter(letter)){
     throw new IllegalArgumentException("Invalid Discount Code");
  }else if(discountCode.indexOf("$") == -1) {
   throw new IllegalArgumentException("Invalid Discount Code");  
   }
    }
  this.discountCode = discountCode.toUpperCase();
    return this.discountCode;
}
}

1 Answer

Hi Cesar,

You've correctly identified that you want to convert the string to a char array and loop through it. You've gone about that in a longer way than is required, though. Try something like:

for(char letter : discountCode.toCharArray()){
  // do stuff
}

Then, you must combine the two conditions else you'll throw an exception when you don't want to. Take your code:

   if(!Character.isLetter(letter)){
     throw new IllegalArgumentException("Invalid Discount Code");
  }

This will throw an exception if the letter is a '$', which isn't what you want. This test is correct !Character.isLetter(letter) but this isn't: if(discountCode.indexOf("$") == -1). The second test will be true if any character is a '$'. You want to test each letter in turn. So, if your discount code is "1codes$" and you're testing the first character; it'll fail (correctly) the isLetter test but the second test will pass as there is a '$' in the string somewhere. Test for the dollar sign at each character, something like letter == '$'.

You'll need to think about the logic here. You want to throw the exception if any character is not a letter and not a dollar sign. Combine those two together; throw the exception if neither test passes.

Lastly, return the uppercased code; don't set this.discountCode - you do that in applyDiscountCode.

Let me know how you get on.

Steve.