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

I cannot think of logical error in the code. The challenge is to keep the first letter m and second letter be upper case

Please find my code attached and let me know if you did not get my question.

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("Member field should start with an m");
          }
    fieldName = fieldName.replace(fieldName.charAt(1),Character.toUpperCase(fieldName.charAt(1)));

    return fieldName;
  }

}

1 Answer

Christopher Augg
Christopher Augg
21,223 Points

Eshan,

The instructions ask for you to validate.

"...Let's write some code to validate the style of the field name ... If the value passed in doesn't meet the requirements, throw an IllegalArgumentException."

Therefore, you need to test for both of the requirements and not use replace.

Hope this helps.

Regards,

Chris