Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

Java Java Objects (Retired) Delivering the MVP Validation

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

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.