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Java Java Objects Delivering the MVP Applying a Discount Code

maor baruch
maor baruch
747 Points

help me

i need help

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

  private String normalizeDiscountCode() {
    discountCode = Character.toUpperCase(discountcode);
   return this.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;
  }
}
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

maor baruch
maor baruch
747 Points

thank you all SOLVED

David Evans
David Evans
10,490 Points

Hi Maor,

You're very close! You're missing a few things though.

The tasks wants you to create a new private method named normalizeDiscountCode which you did.

However, it should accept a parameter that can be passed into it, so this will need to change:

private String normalizeDiscountCode() {

The next step says to return an uppercase version of the parameter that is passed in.

discountCode = Character.toUpperCase(discountcode);

Is very close, however, Java's toUpperCase method does not accept any parameters like you are trying to pass it. Instead you would use the toUpperCase method on the string being passed in itself.

Lastly you need to return the variable that was passed in, not the class property.

return this.discountCode;

You're trying to pass the property with that statement. In addition to that, you haven't actually done anything to the property if that was correct.

An example of a working normalizeDiscountCode method might look like the following, though you can certainly change the variables up a bit.:

 private String normalizeDiscountCode(String discountCode) {
    discountCode = discountCode.toUpperCase();
    return discountCode;
  }

Lastly, the task says you need to change your existing applyDiscountCode method to use the new normalizeDiscountCode method that you just wrote.

Change the following to use the parameter 'discountCode' that you passed in to be used in your normalizeDiscountCode method.

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

Hope I covered everything and that this helps.

Yanuar Prakoso
Yanuar Prakoso
15,196 Points

HI Maor

Here is your main problem lies:

private String normalizeDiscountCode() {
    discountCode = Character.toUpperCase(discountcode);<-- here is the main problem
   return this.discountCode;<-- this method does not recognize this.discountCode

first the toUpperCase method should be utilized like this: discountCode.toUpperCase()

then you must return discountCode variable not this.discountCode variable. You will pass the the upper cased discountCode using the public void applyDiscountCode method

this is how I code:

private String normalizeDiscountCode(String discountCode) {
    return discountCode.toUpperCase();
  }

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

I hope this can help a little