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Java Java Objects (Retired) Delivering the MVP Validation

Grigorij Schleifer
Grigorij Schleifer
10,365 Points
Posted by Grigorij Schleifer
Grigorij Schleifer
10,365 Points

I am trying to solve the validation challenge ...

I have no more ideas why this doesnt work ;(

public class TeacherAssistant {

  public static String validatedFieldName(String fieldName) {

    char mChar = 'm';  
    if(fieldName.charAt(0) != mChar){
     throw new IllegalArgumentException("he second letter in the field name must be uppercased");
    }
    char[] fieldNameChar = fieldName.toCharArray();
    if(Character.isLowerCase(fieldNameChar(charAt(1))){
     throw new IllegalArgumentException("he second letter in the field name must be uppercased");
    }
    return fieldName;
  }

}

1 Answer

Dan Johnson
Dan Johnson
40,533 Points
Dan Johnson
Dan Johnson
40,533 Points

Here's an outline of the changes you could make:

    // The 'm' prefix is typically only used for instance variables, though this
    // won't cause any compilation issues.
    char mChar = 'm';  
    if(fieldName.charAt(0) != mChar) {
     throw new IllegalArgumentException("The first letter should be an \'m\'.");
    }

    char[] fieldNameChar = fieldName.toCharArray();
    // Access elements of an array with [] instead of ().
    // charAt is a method of the String class, so you can't call it on its own.
    if(Character.isLowerCase(fieldNameChar[1])) {
     throw new IllegalArgumentException("The second letter in the field name must be uppercased");
    }

    // For the final check, make sure the second letter is a character.
    // There's a static method of the Character class that can do this.

    // if the second character isn't a letter
    //     throw an exception