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Java Java Objects (Retired) Delivering the MVP Validation

Posted by Mariana Nuta
Mariana Nuta
5,321 Points

How to check if a character is upperCased? I tried Character.isUpperCase(), but it is not imported

How to check if a character is upperCased? I tried Character.isUpperCase(), but it is not imported

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) ) {
     throw new IllegalArgumentException("Fieldname must start with m and second letter to be uppercase");
    }

    return fieldName;
  }

}

1 Answer

jcorum
jcorum
71,830 Points
jcorum
jcorum
71,830 Points

Mariana, I just tried this:

    if(fieldName.charAt(0) != 'm' || Character.isUpperCase(fieldName.charAt(1)) ) {
        throw new IllegalArgumentException("Fieldname must start with m and second letter must be uppercase");
    }

and it compiled.

But I still got a Bummer! because it now says it wants 

m_first_name

to validate. But since Character.isUpperCase('_') is false the test as written won't validate it! I didn't watch the video but the comments in the challenge seem to imply that the only requirements are that an instance variable's name start with m and be camelCased! So looks like you'll need a slightly more complicated or clause.