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Dorukhan Arat
31,325 PointsI'm stuck at Applying the discount code challenge task of 2 in java. Could anyone solve it?
Can anyone show me the solution of this exercise. I'm spend a lot of time on it and I can't find the answer and I'm curious about it.
Bogdan Siverchuk
Courses Plus Student 1,707 PointsI wrote this
if (discountCode.contains("1") || discountCode.contains("@")||discountCode.contains("#"){
throw new Illegal ....(blablabla)
}
And it worked!(maybe cheated but it worked) Allthough idea with loop and Array is good, but not with my skills!
Steve Hunter
57,712 PointsHi Bogdan,
I couldn't get your code to pass the challenge. The exception should be thrown if any number, or any non-letter excluding $, is in the passed-in discount code. You have only tested for one number; 1. If the user's discount code contained a 2, your exception wouldn't be thrown. Same if the discount code contain, for example, a % or a !.
The contains method is useful for many things but not where you want to test for lots of content as you have to write too many conditions.This is where regular expressions are incredibly useful as you can test for lots of content at once. There's a course for those which is very useful.
But the for loop is what this challenge is aimed at as that's relevant to the course content at this point.
Steve.
4 Answers
Steve Hunter
57,712 PointsHi there,
There's a couple of points here. First, don't set this.discountCode in this method. That's done in the applyDiscountCode method. So, remove that line.
Next, the return should send back the upper case version - so add .toUpperCase() on your return line.
Lastly, think about your logic. You've combined the two conditions using ||, an OR condition. You want both conditions (negated, correctly) to be true to throw the exception. You want to compare with &&.
Steve.
Dorukhan Arat
31,325 PointsI'm so grateful for your help steve thanks
Steve Hunter
57,712 PointsNo problem! 
Bogdan Siverchuk
Courses Plus Student 1,707 PointsHi Steve! Based on what we have learned i can say that arrays will be soon,didn't learn it yet. And in videos we didn't have anything like it(cheking for numbers and simbles) or i missed it. I used what i have learned so far and it helped me to check. It is not ideal, where your way would be better. I just do not know how to combine loops and arrays yet.
Steve Hunter
57,712 PointsHi Bogdan,
There's a previous challenge called "counting scrabble tiles" that uses a for loop. The segment of the course prior to that details the use of a for loop to iterate over a string that has been converted to an array. Have a look at around the 5:00 part of this course that precedes the current challenge.
Steve.
Dorukhan Arat
31,325 Pointsprivate String normalizeDiscountCode (String discountCode) {
this.discountCode = discountCode.toUpperCase();
for(char c : discountCode.toCharArray()) {
if (!(Character.isLetter(c)) || !(c == '$')) {
throw new IllegalArgumentException ("Invalid discount code.");
}
}
return discountCode;
}
its look like this but it doesn't return the string uppercase
Bogdan Siverchuk
Courses Plus Student 1,707 PointsSteve! Thank you ! Helped me too with loops and arrays!
Steve Hunter
57,712 PointsNo problem!
Steve Hunter
57,712 PointsSteve Hunter
57,712 PointsCan you post your code - we can then help with correcting that.
Essentially, the method receives the discount code which is a string. You need to iterate over that string using a
forloop (or use a regex) and test each character of the string - you'll want to convert the string into an array of characters to achieve this. If each character is a not letter and not a dollar sign; throw an exception. On completing the loop, assuming no exception has been thrown, return the uppercase version of the received string.Steve.