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Java Java Objects (Retired) Delivering the MVP Validation

Suciu Sorin
Suciu Sorin
2,388 Points


I don't have no idea what i am supposed to do :) and i think i don't really understand the question! Help me please or i will have a heart attack :P!!!


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
     String mFieldName = fieldName  ;
    if(mFieldName != fieldName){
      throw new IllegalArgumentException(" ");

    return fieldName;




The first task that you showd achieve is "1. Member fields must start with an 'm'"

So, your first if condition showd look something like this:

//charAt method returns the character that is passed in the index number

if(!fieldName.charAt(0) == 'm ') { throw new IllegalArgumentException("The first letter showld be m"); }

The second task is "2. The second letter in the field name must be uppercased to ensure camel-casing".

For this I created a variable to store the second character of the incoming variable. It showd be at the top of the method:

char secondLetter = fieldName.charAt(1);

Your second if show be like this:

if(!Character.isUpperCase(secondLetter)) { throw new IllegalArgumentException("The second letter must be upperCase"); }

Hope it helps. Sorry for my english.

1 Answer

Suciu Sorin
Suciu Sorin
2,388 Points

Thank's a lot!It helped:)