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Java Java Objects (Retired) Delivering the MVP Validation

I completely din't und the Challenge.Plss help

I din't understand what to do in this challange.

public class TeacherAssistant {
   String firstName;

  public static String validatedFieldName(fieldName) {
      throw new IllegalArgumentException ("A letter is required");
    fieldName =Character.toLowerCase(firstName);

    // 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;


1 Answer

Michael Hess
Michael Hess
24,512 Points

Hi Alina,

This challenge wants us to make sure a member field begins with a lowercase m and that the second character in the member field is an uppercase letter. Please see the following code:

if (fieldName.startsWith("m") && Character.isUpperCase(fieldName.charAt(1))) {
      return fieldName;
    } else {
      throw new IllegalArgumentException("Invalid field name");

If you have any questions feel free to ask them!