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Java Java Objects (Retired) Delivering the MVP Validation

Posted by Sam Detnon
Sam Detnon
1,363 Points

I'm having some trouble with this challenge! I think my code should pass, but its not.

My code is throwing 'Expected "m_first_name'' as an error.

Can anyone help?

Thanks, Sam

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
    char second =  fieldName.charAt(1);

    if (fieldName.charAt(0) != 'm'){
      throw new IllegalArgumentException("first letter must be M!");
    }
    if (Character.isUpperCase(second)){
      throw new IllegalArgumentException("first letter must be M!");
    }




    return fieldName;
  }

}

3 Answers

Micah Kline
Micah Kline
17,831 Points
Micah Kline
Micah Kline
17,831 Points

Try this...

if (!Character.isUpperCase(second)){
      throw new IllegalArgumentException("second letter must be Capitalized!");
    }
Sam Detnon
Sam Detnon
1,363 Points
Sam Detnon
Sam Detnon
1,363 Points

Well, that was embarrassing!

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"