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Java Java Objects Delivering the MVP Applying a Discount Code

kalyada leosrisook
PLUS
kalyada leosrisook
Courses Plus Student 17,855 Points
Posted by kalyada leosrisook
kalyada leosrisook
Courses Plus Student 17,855 Points

I'm stuck in apply discount code task 2 challenge. I need help.

I've been stuck in this task for a while now. I don't know how to make the code works. If anyone here can help me through this I will be so grateful !

( the question asked me to check if the user enter or the character $. if not throw an IllegalArgumentException)

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)
  {
      return discountCode.toUpperCase(); 

      if ( !Character.isLetter(discountCode) && !discountCode.contains('$') )
      {
          throw new IllegalArgumentException("invalid discount code"); 
      }
  }
  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"
    }

  }
}

3 Answers

Miguel Silva
Miguel Silva
7,757 Points

Try this,

private String normalizeDiscountCode ( String discountCode);{

for (char c: discountCode.toCharArray()) {

if (! Character.isLetter(c) && c != '$'){

throw new IllegalArgumentException ("Invalid discount code.");} } return discountCode.toUpperCase();}

Matt Song
Matt Song
2,971 Points

What does this for code: (char c: discountCode.toCharArray()) do?? I don't understand how does it check for letters? Can someone explain it?

Anubhav Chhabra
Anubhav Chhabra
1,383 Points
Anubhav Chhabra
Anubhav Chhabra
1,383 Points

try using the advanced for loop by splitting up the string to its array using .toCharArray() method. lets hope that it works

Michael Duncan
Michael Duncan
809 Points
Michael Duncan
Michael Duncan
809 Points

This one took me a while to work out. Got there in the end. My code :

private String normalizeDiscountCode(String discountCode) {

for (char c: discountCode.toCharArray()) {

  if (! Character.isLetter(c) && c != '$') {

    throw new IllegalArgumentException("Invalid discount code.");

  }

}

 return discountCode.toUpperCase(); }