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Java Java Objects (Retired) Delivering the MVP Validation

Posted by Kym Bryan Carasig
Kym Bryan Carasig
Courses Plus Student 1,013 Points

Expected "m_first_name" to fail but passed, but i already checked if the char is letter or not. still gives me the error

As the title says guys, i need some help and explanation if you got time. I'm having a hard time since i stopped programming for more than 1 year after graduating. Shame on me.

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'){
      throw new IllegalArgumentException("All members fieldname must start with lower case letter m."); 
    }
    if(Character.isLowerCase(fieldName.charAt(1)) || Character.isLetter(fieldName.charAt(1))){
      throw new IllegalArgumentException("Second letter in fieldname should be a letter and should be camel-cased.");
    }
    return fieldName;


  }

}

2 Answers

Kym Bryan Carasig
PLUS
Kym Bryan Carasig
Courses Plus Student 1,013 Points
Kym Bryan Carasig
Kym Bryan Carasig
Courses Plus Student 1,013 Points

NVM guys. got it! i just forgot the ! sign XD

 if(Character.isLowerCase(fieldName.charAt(1)) || !Character.isLetter(fieldName.charAt(1))){
      throw new IllegalArgumentException("Second letter in fieldname should be a letter and should be camel-cased.");
    }

instead of Character.isLetter(fieldName.charAt(1)) should be !Character.isLetter(fieldName.charAt(1))

Steve Hunter
Steve Hunter
57,712 Points
Steve Hunter
Steve Hunter
57,712 Points

Hi there,

I think the solution can be tidied up a little - there are only two tests (first letter is 'm' and second character is upper case) needed and they both must pass:

public static String validatedFieldName(String fieldName) {

  if(fieldName.charAt(0) == 'm' && Character.isUpperCase(fieldName.charAt(1))) {
     // both things are true - do whatever success looks like
  } else {
     throw new IllegalArgumentException("This does not meet the requirements!");
  }
return fieldName;
}

I hope that makes sense.

Steve.