363: Mainline

Note, that should you declare a variable using an interface, then you can call only those methods that appear in that interface. Thus, even if both the Movie class and the Symphony class define, say, a method named profit, the following will not compile:

public class Demonstrate { 
 public static void main (String argv[]) { 
  // Movie instance assigned to x: 
  RatingInterface x = new Movie (5, 7, 7); 
  System.out.println("The movie's profit is " + x.profit()); 
  // Symphony instance assigned to x: 
  x = new Symphony (7, 5, 5); 
  System.out.println("The symphony's profit is " + x.profit()); 
 } 
}