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Start your free trialAustin Miller
5,171 PointsNot really sure how to check if a String has letters.
On line 24 of Order.java I'm very confused on how I can see if a String has letters in it. The previous lesson video explains how to see if a char has a specific letter in it.
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) {
if (! discountCode.contains("$") || ! discountCode.contains(){
throw new IllegalArgumentException("Invalid discount code");
}
return discountCode.toUpperCase();
}
public void applyDiscountCode(String discountCode) {
this.discountCode = normalizeDiscountCode(discountCode);
}
}
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(); // $ALE
try {
// This will throw an exception because it contains numbers
order.applyDiscountCode("ABC123");
} catch (IllegalArgumentException iae) {
System.out.println(iae.getMessage()); // Prints "Invalid discount code"
}
try {
// This will throw as well, because it contains a symbol.
order.applyDiscountCode("w@w");
}catch (IllegalArgumentException iae) {
System.out.println(iae.getMessage()); // Prints "Invalid discount code"
}
}
}
1 Answer
Steven Parker
231,172 PointsUsing the technique you know for checking a single char, you could loop through the string and check that each char in it meets the criteria.
Also, the parentheses in the "if" statement are unbalanced, the expression needs one more ")" at the end.
Austin Miller
5,171 PointsAustin Miller
5,171 PointsI tried looping it through the String and everything seemed to work but now I'm getting an error that says "order.applyDiscountCode("h1!") and I expected it to throw an IllegalArgumentException, but it didn't". My code looks like it would do the right thing but I seem to be getting different results.
Steven Parker
231,172 PointsSteven Parker
231,172 PointsThe "return" should only be done after the loop finishes. Inside the loop, you only want to throw an exception if a character is bad, and keep checking the other characters if it is OK.
Also, "contains" will check the entire string. Instead, just check if the current character is a "$".
Austin Miller
5,171 PointsAustin Miller
5,171 PointsI followed what you said and it looks like it would work but I'm still getting an error, "java.lang.IllegalArgumentException: Invalid discount code"
Steven Parker
231,172 PointsSteven Parker
231,172 PointsVery close now! I see two remaining issues:
&&
) instead of OR (||
)Austin Miller
5,171 PointsAustin Miller
5,171 PointsIt works! Thank you for your help!