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Courses Plus Student 9,041 PointsPlease help me with this task!
How to check if a String has only letters??
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 boolean isInvalidDiscount(String discountCode) {
boolean isLetterCheck = false;
for(char letter : discountCode.toCharArray()) {
if(! Character.isLetter(letter)) {
isLetterCheck = true;
}
}
return isLetterCheck;
}
private String normalizeDiscountCode(String discountCode) {
String normalizedDiscount = discountCode.toUpperCase();
if( discountCode != "$" || isInvalidDiscount(discountCode)) {
throw new IllegalArgumentException("Invalid discount code.");
}
return normalizedDiscount;
}
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(); // $ALE
try {
// This will throw an exception because it contains numbers
order.applyDiscountCode("ABC123");
} catch (IllegalArgumentException iae) {
System.out.println(iae.getMessage()); // Prints "Invalid discount code"
}
try {
// This will throw as well, because it contains a symbol.
order.applyDiscountCode("w@w");
}catch (IllegalArgumentException iae) {
System.out.println(iae.getMessage()); // Prints "Invalid discount code"
}
}
}
1 Answer
Trent Christofferson
18,846 Pointsin your isInvalidDiscount change
private boolean isInvalidDiscount(String discountCode) {
boolean isLetterCheck = false;
for(char letter : discountCode.toCharArray()) {
if(! Character.isLetter(letter)) {
isLetterCheck = true;
}
}
return isLetterCheck;
}
to
private boolean isInvalidDicount(String discountCode) {
for(char letter : discountCode.toCharArray()) {
if(!Character.isLetter(letter) && letter != '$') {
return true;
}
}
return false;
}
also, change your normalizeDiscountCode to
private String normalizeDiscountCode(String discountCode) {
String normalizedDiscount = discountCode.toUpperCase();
if(isInvalidDicount(discountCode)) {
throw new IllegalArgumentException("Invalid discount code");
}
return normalizedDiscount;
}