Welcome to the Treehouse Community
Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.
Looking to learn something new?
Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.
Start your free trialMassimo Scola
Courses Plus Student 632 PointsnormalizeDiscountCode => check for letters or $ --> ??
So we have to check the String whether it contains anything other than a letter or $ sign.
How am I supposed to do that?
Why can't the author gives us a hint how he wants us to solve this problem?
I'm sure the author dosn't want us to try this: https://stackoverflow.com/questions/5238491/check-if-string-contains-only-letters
as this is a supposed to be a beginners course?
public class Order {
private String itemName;
private int priceInCents;
private String discountCode;
public Order(String itemName, int priceInCents) {
this.itemName = itemName;
this.priceInCents = priceInCents;
}
private String normalizeDiscountCode(String discountCode) {
if (! Character.isLetter(discountCode) )
return this.discountCode = discountCode.toUpperCase();
}
public String getItemName() {
return itemName;
}
public int getPriceInCents() {
return priceInCents;
}
public String getDiscountCode() {
return discountCode;
}
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(); // $ALE
try {
// This will throw an exception because it contains numbers
order.applyDiscountCode("ABC123");
} catch (IllegalArgumentException iae) {
System.out.println(iae.getMessage()); // Prints "Invalid discount code"
}
try {
// This will throw as well, because it contains a symbol.
order.applyDiscountCode("w@w");
}catch (IllegalArgumentException iae) {
System.out.println(iae.getMessage()); // Prints "Invalid discount code"
}
}
}
7 Answers
Massimo Scola
Courses Plus Student 632 Pointsif (!Character.isLetter(c) && c!='$'){
that's it
Massimo Scola
Courses Plus Student 632 PointsI have been "WTF" for quite some time now and I do not know how to proceed.
I have tried this code here
private String normalizeDiscountCode(String discountCode) { this.discountCode = discountCode.toUpperCase(); for (char c : discountCode.toCharArray()) { if (! Character.isLetter(c)) { throw new IllegalArgumentException("Invalid discount code"); } } return this.discountCode; }
So this code checks whether the character is a letter or not. How do I exclude the $ sign?
Lucian Ciopec
12,778 PointsI did it like this:
if (! Character.isLetter(c) || c!= '$')
It compiles, but now I get the message: Oops! It looks like Task 1 is no longer passing. So i need to figure this out now.
Lucian Ciopec
12,778 PointsThis is my code:
public class Order { private String itemName; private int priceInCents; private String discountCode;
public Order(String itemName, int priceInCents) { this.itemName = itemName; this.priceInCents = priceInCents; }
public String getItemName() { return itemName; }
public int getPriceInCents() { return priceInCents; }
public String getDiscountCode() { return discountCode; }
public void applyDiscountCode(String discountCode) { this.discountCode = normalizeDiscountCode(discountCode); }
private String normalizeDiscountCode(String discountCode) {
for(char c : discountCode.toCharArray()) {
if(! Character.isLetter(c) || c != '$') {
throw new IllegalArgumentException("Invalid discount code");
}
}
return discountCode.toUpperCase();
}
}
Lucian Ciopec
12,778 PointsMaybe I need to add the try catch block in the applyDiscountCode() method
Massimo Scola
Courses Plus Student 632 PointsI had exactly the same code like yours and it is just frustrating if we can't proceed.
Maybe there is a technique which hasn't been shown in this presentation.
Lucian Ciopec
12,778 PointsYes, you're right, thank you!
Cristen Hewett
23,811 PointsCristen Hewett
23,811 PointsYES - that's it. thanks