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Java Java Objects (Retired) Delivering the MVP Validation

ms2030
ms2030
2,973 Points
Posted by ms2030
ms2030
2,973 Points

What's wrong with this code challenge?

Error reported: Bummer! "mFirstName" should have passed but invalid field name was reported.

I tested it with java-repl and it works.

TeacherAssistant.java 
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
    if (!(fieldName.indexOf(0) == 'm' && Character.isUpperCase(fieldName.toCharArray()[1]))) {
      throw new IllegalArgumentException("Invalid field name");     
    }

    return fieldName;
  }

}

2 Answers

Harry James
Harry James
14,780 Points
Harry James
Harry James
14,780 Points

Hey ms2030!

If you change the && in your if statement to a || then the challenge will pass :)

The reason being is that the code challenge will want to throw an exception if either the first character is a capital or if the second character isn't a capital - not just when both are done wrong.

Hope it helps!

ms2030
ms2030
2,973 Points
ms2030
ms2030
2,973 Points

Thanks!

Jess Sanders
Jess Sanders
12,086 Points
Jess Sanders
Jess Sanders
12,086 Points 
private 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"