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Java Java Objects (Retired) Delivering the MVP Validation

Priya Patil
Priya Patil
2,471 Points
Posted by Priya Patil
Priya Patil
2,471 Points

Can you please let me know what i am doing wrong here? please it will be very helpful

Can you please help in resolving this error

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
    char letter;
    if(!(fieldName.charAt(0) == 'm')) 
    {
      throw new IllegalArgumentException(" it should start with m");
    }
    letter = fieldName.charAt(1);
      Character.toLoweCase(letter);


    return fieldName;
  }

}

3 Answers

Sivasuryateja Raparla
Sivasuryateja Raparla
3,966 Points
Sivasuryateja Raparla
Sivasuryateja Raparla
3,966 Points

The 2 test ask to check whether or not the second character in the string is UpperCase. You can do that by checking the below statement in an if condition if( !Character.isUpperCase(fieldName.charAt(1))) { throw new IllegalArgumentException(" The second letter in the field name must be uppercased to ensure camel-casing"); }

Priya Patil
Priya Patil
2,471 Points
Priya Patil
Priya Patil
2,471 Points

Thank you so much for your response.

Priya Patil
Priya Patil
2,471 Points
Priya Patil
Priya Patil
2,471 Points

Thank you so much for your response.

Sivasuryateja Raparla
Sivasuryateja Raparla
3,966 Points
Sivasuryateja Raparla
Sivasuryateja Raparla
3,966 Points 
if( !Character.isUpperCase(fieldName.charAt(1))) { 
throw new IllegalArgumentException(" The second letter in the field name must be uppercased to ensure camel-casing");
 }
Craig Dennis
STAFF
Craig Dennis
Treehouse Teacher
Craig Dennis
Craig Dennis
Treehouse Teacher

toLoweCase is missing an r. But I think you want Character.isUpperCase.

if(!(fieldName.charAt(0) == 'm'))

Is better stated:

if(fieldName.charAt(0) != 'm')
Priya Patil
Priya Patil
2,471 Points
Priya Patil
Priya Patil
2,471 Points

Thank you so much for your response.

Sivasuryateja Raparla
Sivasuryateja Raparla
3,966 Points
Sivasuryateja Raparla
Sivasuryateja Raparla
3,966 Points

if(!(fieldName.charAt(0) != 'm')) It goes into the if block only if the condition is false and it can only be false if the first character is 'm'. But in the if block we are throwing a exception..so the if condition should say if((fieldName.charAt(0) != 'm')) without the negation to goes inside the if statement to throw the exception

Craig Dennis
Craig Dennis
Treehouse Teacher
Craig Dennis
Craig Dennis
Treehouse Teacher

Sorry..typo...edited. Thanks Sivasuryateja