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Start your free trialSohaib Rashid
627 PointsIf someone can walk me through this, i would highly appreciate it! I know i have to use an if loop but I've tried
ive tried a lot of different ways but there always seems to be an error! Happy Coding! the task is : So I was wondering if you could help me with some of these code challenges. As you might've seen when a member field name doesn't match the style we've talked about, I send an error about it. Let's write some code to validate the style of the field name.
I've added the method validatedFieldName it will return the validated field name. If the value passed in doesn't meet the requirements, throw an IllegalArgumentException. I'll keep you posted on the results every time you press check work.
public class TeacherAssistant {
public static String validatedFieldName(String fieldName) {
// These things should be verified:
// 1. Member fields must start with an 'm'
// 2. The second letter in the field name must be uppercased to ensure camel-casing
// NOTE: To check if something is not equal use the != symbol. eg: 3 != 4
return fieldName;
}
}
3 Answers
Rob Bridges
Full Stack JavaScript Techdegree Graduate 35,467 PointsHello!
So the first thing we want to do is make sure that the first character in the field name is the character 'm'
We can do this by the following
if (fieldName.charAt(0) != 'm')
The second part is we want to make sure that the second letter is captial, we can do this by.
if (!Character.isUpperCase(fieldName.charAt(1))
To combine it all together it would look something like below.
public class TeacherAssistant {
public static String validatedFieldName(String fieldName) {
// These things should be verified:
if (fieldName.charAt(0) != 'm' || !Character.isUpperCase(fieldName.charAt(1)) ) {
throw new IllegalArgumentException("Illegal field name");
}
// 2. The second letter in the field name must be uppercased to ensure camel-casing
// NOTE: To check if something is not equal use the != symbol. eg: 3 != 4
return fieldName;
}
}
Jess Sanders
12,086 Pointsprivate char validateGuess(char letter) {
if (!Character.isLetter(letter)) {
throw new IllegalArgumentException("A letter is required."
}
letter = Character.toLowerCase(letter);
if (mMisses.indexOf(letter) >= 0 || mHits.indexOf(letter) >= 0) {
throw new IllegalArgumentException(letter + " has already been guessed") }
return letter;
}
- The above code is the example to follow.
- We care about charAt for this challenge, rather than indexOf
- In pseudocode, we want to check for the following condition, and throw an error: " if the character at index 0 of fieldName does not equal 'm' OR the character at index 1 of fieldName is not upper case"
Unsubscribed User
3,091 PointsThat mostly makes sense, what I am not getting is where does Character come from? What is Character
from Character.toLowerCase(letter) or !Character.isLetter
Rob Bridges
Full Stack JavaScript Techdegree Graduate 35,467 PointsHey Brendon.
Character is a defined class already in Javascript, so that's why you're not seeing it defined anywhere, it's actually a wrapper class that you can call methods on if you pass it in the valuable of char like in this instance where we
Character.isUpperCase(fieldName.charAt(1));
We're actually just calling the Character class, and passing it in a char as a value, in this instance to check and see if the certain character is upperCase.
Thanks.
Sohaib Rashid
627 PointsSohaib Rashid
627 PointsThanks man! You have a great way of explaining! A lot of help, thanks and happy coding!
Rob Bridges
Full Stack JavaScript Techdegree Graduate 35,467 PointsRob Bridges
Full Stack JavaScript Techdegree Graduate 35,467 PointsGlad to hear that it helped. Happy coding!