Compare two character for sequence in Java

/*w  ww  .  jav  a 2  s  .c o  m*/
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public class Main {
  public static void main(String args[]) {
    Character a = new Character('a');
    Character a2 = new Character('a');
    Character b = new Character('b');

    int difference = a.compareTo(b);

    if (difference == 0) {
      System.out.println("a is equal to b.");
    } else if (difference < 0) {
      System.out.println("a is less than b.");
    } else if (difference > 0) {
      System.out.println("a is greater than b.");
    }

    System.out.println("a is " + ((a.equals(a2)) ? "equal" : "not equal")
        + " to a2.");

    System.out.println("The character " + a.toString() + " is "
        + (Character.isUpperCase(a.charValue()) ? "upper" : "lower")
        + "case.");
  }
}