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Java Java Objects (Retired) Delivering the MVP Validation

Ruslan Baidauletov
Ruslan Baidauletov
2,734 Points

Expected "m_first_name" to fail but it passed

I can't find a mistake.

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("m letter");
    char secLetter = fieldName.charAt(1);

    if (Character.isLowerCase(secLetter)) {
      throw new IllegalArgumentException("lowercase letter");

    return fieldName;


1 Answer

Charles Cloud
Charles Cloud
6,134 Points

Your code is checking if the second character is lower case and throwing an exception only if it is. An underscore is not lowercase therefore it is not throwing an exception