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Java Java Objects (Retired) Delivering the MVP Validation

Alistair Mackay
Alistair Mackay
7,812 Points
Posted by Alistair Mackay
Alistair Mackay
7,812 Points

Java Objects: Validation - this one's tricky.

Having trouble getting this exercise to pass and I don't understand the error message I get back when I press "Check Work" - "Bummer! Expected "m_first_name" to fail but it passed."

I feel like I may have went off piste with my answer, the code compiles fine and from what I can tell should work but it's not passing the example.

public class TeacherAssistant {

  public static String validatedFieldName(String fieldName) {
    char[] fieldNameArray = fieldName.toCharArray();
    // These things should be verified:
    if (fieldNameArray[0] != 'm') {
      // 1.  Member fields must start with an 'm'
      throw new IllegalArgumentException("variable fieldName must start with an the char 'm'");
    }
    if (Character.isUpperCase(fieldNameArray[1])) {
      // 2.  The second letter in the field name must be uppercased to ensure camel-casing
      throw new IllegalArgumentException("second letter in filedName must be capitalised.");
    }
    // NOTE:  To check if something is not equal use the != symbol. eg: 3 != 4
    return fieldName;
  }

}

Any pointers on how to pass this example?

2 Answers

Craig Dennis
STAFF
Craig Dennis
Treehouse Teacher
Craig Dennis
Craig Dennis
Treehouse Teacher

Looks good! I think you mean not uppercase tho!

Did you get this solved already?

Alistair Mackay
Alistair Mackay
7,812 Points
Alistair Mackay
Alistair Mackay
7,812 Points

Yeah got there in the end - took me a while to spot where I had went wrong.

Thanks for the course! :-)

The following got it to pass, I had seen a few cleaner ways to do this that didn't use an "fieldNameArray" variable, but I was happy enough with the answer.

public class TeacherAssistant {

  public static String validatedFieldName(String fieldName) {
    char[] fieldNameArray = fieldName.toCharArray();
    // These things should be verified:
    if (fieldNameArray[0] != 'm') {
      // 1.  Member fields must start with an 'm'
      throw new IllegalArgumentException("variable fieldName must start with an the char 'm'");
    }
    if (!Character.isUpperCase(fieldNameArray[1])) {
      // 2.  The second letter in the field name must be uppercased to ensure camel-casing
      throw new IllegalArgumentException("second letter in filedName must be capitalised.");
    }
    // NOTE:  To check if something is not equal use the != symbol. eg: 3 != 4
    return fieldName;
  }

}