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Java Java Objects Delivering the MVP Applying a Discount Code

Posted by nandup
nandup
5,183 Points

I want to accept as input only English alphabetic letters and dollar symbol... How can I write code for this condition

I have a trouble writing 'to accept dollar as input'.

Order.java 
public class Order {
  private String itemName;
  private int priceInCents;
  private String discountCode;

  private String normalizeDiscountCode(String discountCode){
    if(!String.isLetter(discountCode) || !String.equals('$')){
      throw new IllegalArgumentException("Invalid discount code");
    }

    discountCode =   discountCode.toUpperCase();
    return 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 = normalizeDiscountCode(discountCode);
    this.discountCode = discountCode.toUpperCase();

  }
}

1 Answer

Samuel Ferree
Samuel Ferree
31,722 Points
Samuel Ferree
Samuel Ferree
31,722 Points

It's a bit of an advanced topic, and treehouse has a course on it, but this is an ideal problem to solve with regular expressions

nandup
nandup
5,183 Points

Thank you very much :)

nandup
nandup
5,183 Points

But I'm unable to find solution for this question..

Samuel Ferree
Samuel Ferree
31,722 Points
Samuel Ferree
Samuel Ferree
31,722 Points

Oh sorry, I didn't see that that this question was part of a challenge.

the isLetter method is a member of Character, not String, so you'll need to loop through each character in the discount code to check instead of checking on the string as a whole.

  private String normalizeDiscountCode(String discountCode) {
    for(int i = 0; i < discountCode.length(); i++) {
      char ch = discountCode.charAt(i);
      if(!(Character.isLetter(ch) || ch == '$')) { // if character is not a letter or '$'
        throw new IllegalArgumentException();
      }
    }
    return discountCode.toUpperCase();
  }