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Java Java Objects (Retired) Delivering the MVP Validation

Posted by Michael Harper
Michael Harper
14,741 Points

Validation test failing

No compiler errors are thrown in Preview, but solution fails with error: Bummer! Expected "m_first_name" to fail but it passed.

Where is "m_first_name" coming from in this example?

TeacherAssistant.java 
public class TeacherAssistant {

  public static String validatedFieldName(String fieldName) {
    // These things should be verified:

    // 1.  Member fields must start with an 'm'
    if ( fieldName.charAt(0) != 'm') {
        throw new  IllegalArgumentException("member field " +fieldName+ " doesn't start with m.");
      }

 // 2.  The second letter in the field name must be uppercased to ensure camel-casing
    boolean lowCase = Character.isLowerCase(fieldName.charAt(1));
    if (lowCase) {   
        throw new  IllegalArgumentException("member field " +fieldName+ " second char is not upper case.");
    }
    return fieldName;
  }
}

1 Answer

Grigorij Schleifer
Grigorij Schleifer
10,363 Points
Grigorij Schleifer
Grigorij Schleifer
10,363 Points

Hi MIchael,

you can use this:

boolean lowCase  = Character.isUpperCase(fieldName.charAt(1);

or:

 if (!Character.isUpperCase(fieldName.charAt(1))) {
            throw new IllegalArgumentException("some massage"); 
        }

for the upper case examination.

Grigorij

Michael Harper
Michael Harper
14,741 Points

Thanks G, using isUpperCase() instead of isLowerCase() seems to deal with illegal characters in a more expected way.

Grigorij Schleifer
Grigorij Schleifer
10,363 Points
Grigorij Schleifer
Grigorij Schleifer
10,363 Points

Hey M :smiley:

the logic of your code is good, but I think the challenge wants us to use isUpperCase() method.

See you in the forum

G