test whether the null reference is an instance of a class. This will always result in false. : instanceof Operator « Operators « SCJP

1. SCJP
2. Operators
3. instanceof Operator

class MainClass {
   public static void main(String [] args) {
      String a = null;
      boolean b = null instanceof String;
      boolean c = a instanceof String;
      System.out.println(b + " " + c);
   }
}

false false