Null reference

Question

hi guys..!
plz can anyone explain the output of the code below...
public class AQuestion
public void method(Object o)
System.out.println("Object Version");
public void method(String s)
System.out.println("String Version");
public static void main(String args[])
AQuestion question = new AQuestion();
question.method(null);
thanx in advance....
regards,
j-c

Answer 1

In case over overloaded methods, Java wil try to find the best, and most excplicitly defined method. String is more explicit than Object, so that one is chosen. It is valid, since a String object CAN be null.
Following WILL print "object version", since int cannot be null:
public class AQuestion {
   public void method(Object o) {
      System.out.println("Object Version");
   public void method(int i) {
      System.out.println("int Version");
   public static void main(String args[]) {
      AQuestion question = new AQuestion();
      question.method(null);
}