public class Charactertest {
   public static void main(String args[]) {
     char letter = 'd';
     boolean lowerCase = Character.isLowerCase(letter);
     boolean upperCase = Character.isUpperCase(letter);
     boolean letterOrdigit = Character.isLetter(letter);
     System.out.println("Is this letter lowercase? " + lowerCase);
     System.out.println("Is this letter uppercase? " + upperCase);
     System.out.println("Is this a letter? " + letterOrdigit);
   }
}