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Java Java Objects (Retired) Delivering the MVP Validation

Can someone please elaborate on what this exercise is asking for?

what are the requirements that this question is talking about? Is it that the fieldName needs to contain only letters and that it has to be all lower case?

public class TeacherAssistant {

  public static String validatedFieldName(String fieldName) {
       if (){
      throw new IllegalArgumentException("Does not meet the requirements");
    // 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

Miguel Canas
Miguel Canas
Python Development Techdegree Student 11,470 Points

Hi brenoannes,

This exercise is asking you to verify that the fieldName argument passes the rules defined in the comment.

You can read the rules as:

  • The first letter of fieldName must be "m"
  • The second letter of fieldName must be uppercase.

If fieldName passes these rules, return the fieldName. Otherwise, throw an IllegalArgumentException.

For example:

  • If I were to call validateFieldName("foobar") I expect to get an IllegalArgumentException.
  • If I were to call validateFieldName("fooBar") I expect to get an IllegalArgumentException.
  • if I were to call validateFieldName("mFoobar") I expect the return value to be "mFoobar".

Hope that helps,

  • Miguel

Geez, my bad, I was overthinking as I had the previous lesson in mind. Some times you forget how simple these exercises are meant to be. Thank you Miguel.