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Java Java Objects (Retired) Delivering the MVP Validation

Posted by Gem Knight
Gem Knight
4,779 Points

I need help

Can somebody please help me fix my code.

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.charAt(1) != fieldName.charAt(1).toUppperCase()) {
      throw new IllegalArgumentExeption("%s, is not a valid field name...", fieldName);
    }
    return fieldName;
  }

}

2 Answers

Jeremy Hill
Jeremy Hill
29,567 Points
Jeremy Hill
Jeremy Hill
29,567 Points

Here try this:

public class TeacherAssistant {

  public static String validatedFieldName(String fieldName) {

    if(fieldName.charAt(0) != 'm' || (!(Character.isUpperCase(fieldName.charAt(1)))))
      throw new IllegalArgumentException("Not a valid field name");
    else
    return fieldName;
  }

}
Grigorij Schleifer
Grigorij Schleifer
10,365 Points
Grigorij Schleifer
Grigorij Schleifer
10,365 Points

Hi Gem,

your logic is fine but this challenge is really challenging :)

First some errors I have found in your code:

  • A typo in IllegalArgumentExeption (a missing 'c' in exception)
  • don´t try to format the exception text (there is no printf function available)
  • use the Character class and its static methods (isUpperCase() and isLetter()) to build the if condition
public class TeacherAssistant {

  public static String validatedFieldName(String fieldName) {
    if (fieldName.charAt(0) != 'm' || ! Character.isUpperCase(fieldName.charAt(1)) || ! Character.isLetter(fieldName.charAt(1))) {
// first condition proofs if the irst char is 'm'
// second condition proofs if the second char is uppercased
// third condition proofs if the char is a letter to avoid this error (Expected "m_first_name" to fail but it passed)
      throw new IllegalArgumentException("Not a valid field name...");
    }
    return fieldName;
  }
}

I hope this helps

Grigorij