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Java Java Objects (Retired) Delivering the MVP Validation

Posted by Eshan Anand
Eshan Anand
7,277 Points

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
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