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Java Java Objects (Retired) Delivering the MVP Validation

soo ao long tian
soo ao long tian
1,111 Points
Posted by soo ao long tian
soo ao long tian
1,111 Points

how to solve this?

how to solve this quiz?

TeacherAssistant.java 
public class TeacherAssistant {

  public static String mFieldName;

  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 != mFieldName){
    throw new IllegalArgumentException( "is not allowed" );

    }




    return fieldName;
  }

}

3 Answers

Simon Coates
Simon Coates
28,694 Points
Simon Coates
Simon Coates
28,694 Points

my guess is:

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
    char firstChar = fieldName.charAt(0);
    char secondChar = fieldName.charAt(1);
    if(firstChar =='m' && Character.isUpperCase(secondChar)) {
      // NOTE:  To check if something is not equal use the != symbol. eg: 3 != 4
      return fieldName;
    } else {
      throw new IllegalArgumentException("Does not meet criteria");
    }
  }
}
soo ao long tian
soo ao long tian
1,111 Points
soo ao long tian
soo ao long tian
1,111 Points

i try to use the != because the note wrote // NOTE: To check if something is not equal use the != symbol. eg: 3 != 4

but it doesn't work, is there anything wrong with my code?

it show me Bummer! Expected "m_first_name" to fail but it passed.

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 firstChar = fieldName.charAt(0);
    char secondChar = fieldName.charAt(1);

    if(firstChar != 'm' && Character.isLowerCase(secondChar) ){
    throw new IllegalArgumentException("doesn't meet requirement");

    }else{
    return fieldName;
    }
  }

}
Simon Coates
Simon Coates
28,694 Points
Simon Coates
Simon Coates
28,694 Points

maybe:

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
    char firstChar = fieldName.charAt(0);
    char secondChar = fieldName.charAt(1);
    if(firstChar !='m' || !Character.isUpperCase(secondChar)) {
      // NOTE:  To check if something is not equal use the != symbol. eg: 3 != 4
     throw new IllegalArgumentException("Does not meet criteria");

    } else {
        return fieldName;
    }
  }
}
soo ao long tian
soo ao long tian
1,111 Points
soo ao long tian
soo ao long tian
1,111 Points

wow, that reply was fast, i know where is my mistake now, thanks