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Start your free trialSiddesh Gannu
3,565 PointsnormalizeDiscountCode $@ving$ testcase working
I'm trying to run the code and it keeps saying that IllegalArgumentException should be called when the input: $@ving$ is put in. Why and how is $@ving$ even working? Isn't my for loop iterating through all the letters in the String. Then how is the '@' being allowed through? Is the @ symbol being considered as a letter? Thanks to anyone that answers this!
public class Order {
private String itemName;
private int priceInCents;
private String discountCode;
private String normalizeDiscountCode (String dCode){
discountCode = dCode.toUpperCase();
char[] cArr = discountCode.toCharArray();
for(char c : cArr) {
if(!Character.isLetter(c) && discountCode.indexOf('$') == -1) {
throw new IllegalArgumentException("Invalid discount code");
}
}
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;
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(); // $ALE
try {
// This will throw an exception because it contains numbers
order.applyDiscountCode("ABC123");
} catch (IllegalArgumentException iae) {
System.out.println(iae.getMessage()); // Prints "Invalid discount code"
}
try {
// This will throw as well, because it contains a symbol.
order.applyDiscountCode("w@w");
}catch (IllegalArgumentException iae) {
System.out.println(iae.getMessage()); // Prints "Invalid discount code"
}
}
}
1 Answer
Gergely Horvath
Courses Plus Student 8,207 PointsThere are two problems with your code: 1) in your normalizeDiscountCode method you overwrite the content of the instance variable discountCode
private String normalizeDiscountCode (String dCode){
discountCode = dCode.toUpperCase(); // <-- this line
Declare your variable in the scope of normalizeDiscountCode method:
private String normalizeDiscountCode (String dCode){
String discountCode = dCode.toUpperCase(); // <-- this line
2) while looping through characters of discountCode you use indexOf method that is a loop also. So there is an unnecessary loop in your loop. Use simple checking of equality here:
c == '$'
Then you have to think of the truth table, and find out which bitwise operator can be helpful here.
One solution would be using your code:
private static String normalizeDiscountCode2 (String dCode) {
String discountCode = dCode.toUpperCase();
char[] cArr = discountCode.toCharArray();
for(char c : cArr) {
if(!Character.isLetter(c) ^ c == '$') {
throw new IllegalArgumentException("Invalid discount code");
}
}
return discountCode;
}
My solution:
```Java
private String normalizeDiscountCode(String discountCode) {
boolean b = true;
int i = 0;
while (b && i < discountCode.length()) {
char c = discountCode.charAt(i);
b &= Character.isLetter(discountCode.charAt(i)) ^ c == '$';
i++;
}
if(!b) throw new IllegalArgumentException("Invalid discount code");
return discountCode.toUpperCase();
}
Maybe it's not the most elegant one, but it works, and it doesn't break a for loop.
Gergely Horvath
Courses Plus Student 8,207 PointsGergely Horvath
Courses Plus Student 8,207 PointsSorry, i forgot to close a code block before the "My solution" line. And i can't edit my answer. Why isn't there at least a preview function? Also i could change "discountCode.charAt(i)" to "c" in my while loop.
Gergely Horvath
Courses Plus Student 8,207 PointsGergely Horvath
Courses Plus Student 8,207 PointsOh there is a preview function, i just failed to see the button in the bottom right corner. :(