Changing a Reference Parameter

Here is an altered program in which the print() method changes the value held in its formal parameter.

class ObjectPrinter2
{
  public void print( String st )
  {
    System.out.println("First value of parameter: " + st );

    st = "Hah! A second Object!" ;

    System.out.println("Second value of parameter: " + st );

  }
}

class OPTester2
{
  public static void main ( String[] args )
  {
    String message = "Original Object" ;


    ObjectPrinter op = new ObjectPrinter();

    System.out.println("First  value of message: " + message );    

    op.print( message );

    System.out.println("Second value of message: " + message );    
  }
}