Can't convert String to uppercase

Question

Code Challenge:

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.

I don't understand my error as shown below ./Order.java:7: error: incompatible types: String cannot be converted to Locale discountCode = String.toUpperCase(discountCode); ^

Order.java

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

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

  }
}

Answer 1 · 2018-12-11T19:18:01Z

December 11, 2018 7:18pm

A few things that you need to change are :

The normalize method needs to take in a string aka the discount code as a parameter
The normalize method then needs to return it's upper case version. To do this, you need take an instance of a string and not it's string class e.g "Hello".toUpperCase() and not String.toUpperCase("Hello")
Then in the applyDiscountCode method, you need to assign the return of the nomalize method to the discountCode member field.

Hope this helps.

This should be the correct code:

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 = normalizeDiscountCode(discountCode);
  }

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

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Tashfin Shahid

Tashfin Shahid

Can't convert String to uppercase

1 Answer

Daniel Turato

Daniel Turato