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Java Java Objects Delivering the MVP Applying a Discount Code

David Park
David Park
1,953 Points

no suitable method..

Do not understand the problem here. Error says that there is "no suitable method found for toUpperCase(String)". discountCode is already marked a string based on the declaration above. Any help is appreciated. D

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;
  }

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

  private String normalizeDiscountCode(String discountCode) {
    this.discountCode = Character.toUpperCase(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"
    }

  }
}

1 Answer

Jethro Ocean
Jethro Ocean
2,458 Points

The task was:

"For this first task, create a new private method named normalizeDiscountCode. It should take the discount code that is passed into the method and return the uppercase version. Call it from the current applyDiscountCode method and set this.discountCode to the result. "

The argument in making a string become all capital letters is: <StringName>.toUpperCase()

Thus, your code should look like this:

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

Afterwards, you have another task on calling that method in your applyDiscountCode method and setting the result of that normalization to this.discountCode.

Thus, the code will look like this.

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