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Java Java Objects (Retired) Delivering the MVP Validation

Christopher Harris
Christopher Harris
1,166 Points

help on task

Expected "m_first_name" to fail but it passed. how can m get through when i have set it so first letter of the fieldName can't be m ?

public class TeacherAssistant {

  public static String validatedFieldName(String fieldName) {

    char startingLetter = fieldName.charAt(0);
    if (startingLetter != 'm'){
      throw new IllegalArgumentException ("wrong starting letter");
     // 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
    return fieldName;


1 Answer

serena chan
serena chan
iOS Development Techdegree Student 3,606 Points

It seems that the code here throws an illegal argument exception if the first letter of what you pass in is 'm'. According to your code, in line 6, if starting letter is NOT m an illegal argument exception will be thrown.

To make the method throw the exception if first letter IS m, change line 6's != to ==.