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Java Java Objects (Retired) Delivering the MVP Validation

Matthew Fueglein
Matthew Fueglein
640 Points
Posted by Matthew Fueglein
Matthew Fueglein
640 Points

my code isn't passing, not sure why. can someone check it out please?

i'm supposed to throw an exception if fieldName doesn't start with an 'm' or if the second char isn't uppercase.

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
    if(fieldName.charAt(0)!= 'm') {
      throw new IllegalArgumentException("A m is required");
    }
    if(Character.isLowerCase(fieldName.charAt(1)))
       {
      throw new IllegalArgumentException("A uppercase is required");
    }
      return fieldName;
  }

}

1 Answer

Ryan Field
PLUS
Ryan Field
Courses Plus Student 21,242 Points
Ryan Field
Ryan Field
Courses Plus Student 21,242 Points

Hi Matthew,

This challenge is trying to trick you. If you look carefully at the error message, it says it tried passing 'm_first_name' and expected it to fail, but it passed. The second character here is an underscore, so you need to also check whether the second character is, in fact, a letter. You can use the isLetter() method to determine that.