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Java Java Objects (Retired) Delivering the MVP Validation

Donna Norris
Donna Norris
5,197 Points
Posted by Donna Norris
Donna Norris
5,197 Points

don't know why this doesn't work

It's asking me to throw an exception if the second letter in the field name is not uppercase.

char[] charFieldName=fieldName.toCharArray();

    if (charFieldName[1].isLowerCase()){
  throw new IllegalArgumentException("Must use camel case");
}
TeacherAssistant.java 
public class TeacherAssistant {

  public static String validatedFieldName(String fieldName) {
    char[] charFieldName=fieldName.toCharArray();
    if (charFieldName[0]!='m'){
      throw new IllegalArgumentException("Must begin with 'm'");
    }
        if (charFieldName[1].isLowerCase()){
      throw new IllegalArgumentException("Must use camel case");
    }
    // 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
    return fieldName;
  }

}

2 Answers

Rebecca Rich
PLUS
Rebecca Rich
Courses Plus Student 8,592 Points
Rebecca Rich
Rebecca Rich
Courses Plus Student 8,592 Points

Your issue is with:

charFieldName[1].isLowerCase()

charFieldName[1] is a character. The isLowerCase() method is a static method, so it needs to be used like this:

Character.isLowerCase(charFieldName[1])