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Java Java Objects (Retired) Delivering the MVP Validation

Posted by Unsubscribed User
Unsubscribed User
1,691 Points

What am i doing wrong?

The problem ask me to check if the first letter is m and if the second letter is uppercase i should return the validated field name, but if not i should throw an exception, what exactly am i doing wrong?

Thanks in advance.

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' && fieldName.chartAt(1).isUpperCase() == true)
    return fieldName;   
    else
      throw new IllegalArgumentException("The fieldname cannot be validated because it doesn't meet the requirements!");
  }

}

1 Answer

Jennifer Nordell
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STAFF
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Jennifer Nordell
Treehouse Teacher
Jennifer Nordell
.a{fill-rule:evenodd;}techdegree
Jennifer Nordell
Treehouse Teacher

Hi there! You're doing great and hang in there! But there's a few things going on here. One is simply a typo. When your'e trying to check that the second letter is upper case, you've misspelled charAt with chartAt. Again the second problem comes with checking for that upper cased second letter. isUpperCase is a method to be called on the Character object and then we pass in a character to the method.

:warning: SPOILER ALERT

This is how I did it. :information_source: Note that the curly braces in the if/else blocks are optional as you only have one line of code there. But I prefer them.

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' && Character.isUpperCase(fieldName.charAt(1))) {
      return fieldName;
    }
    else {
      throw new IllegalArgumentException("The fieldname cannot be validated because it doesn't meet the requirements!");
    }
  }
}

Happy coding and good luck! :thumbsup:

Unsubscribed User
Unsubscribed User
1,691 Points

Thanks, it worked, i will pay more attention next time :)