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Java Java Objects Delivering the MVP Applying a Discount Code

coskun olcucu
coskun olcucu
5,340 Points
Posted by coskun olcucu
coskun olcucu
5,340 Points

My code doesn't work!!!

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) {
        char [] ch=discountCode.toCharArray();
        for(int i=0; i<ch.length; i++) {
            if(ch[i]!='$'|| !Character.isLetter(ch[i])) {
                  throw new IllegalArgumentException("Invalid code");

            }
        }
        return discountCode.toUpperCase();
    }
    public void applyDiscountCode(String discountCode) {
        this.discountCode=normalizeDiscountCode(discountCode);
    }
}

Can you look up normalizeDiscountCode method that is supposed to throw an error message if the character is either '$' nor number.

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 String getItemName() {
    return itemName;
  }

  public int getPriceInCents() {
    return priceInCents;
  }

  public String getDiscountCode() {
    return discountCode;
  }
   private String normalizeDiscountCode(String discountCode){
           char [] ch=discountCode.toCharArray();
            for(int i=0; i<ch.length; i++) {
                     if(ch[i]!='$' ||  !(Character.isLetter(ch[i]))) {
                            throw new IllegalArgumentException("Invalid code");
                     }
              }
        return discountCode.toUpperCase();
   }
  public void applyDiscountCode(String discountCode) {
    this.discountCode = normalizeDiscountCode(discountCode);
  }
}
Example.java 
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

Timothy Hilley
Timothy Hilley
2,292 Points
Timothy Hilley
Timothy Hilley
2,292 Points 
  public void applyDiscountCode(String discountCode) {
    discountCode = normalizeDiscountCode(discountCode);
    this.discountCode = discountCode;
  }

  private String normalizeDiscountCode(String code) {
    String normalizedCode = code.toUpperCase();
     if(!normalizedCode.matches("^[A-Z$]+$")) { ^ = from the beggining +$ to the end of each word allow "[these]" only
       throw new IllegalArgumentException("Invalid Discount Code");
     }
    return normalizedCode;
  }
coskun olcucu
coskun olcucu
5,340 Points
coskun olcucu
coskun olcucu
5,340 Points

First of all, thank you for your response. How about my code inside my code i convert the string an array of character and for loop is checking every character inside the for loop.What is the logical mistake on my code?