OOP/Polymorphism question

programming flash
1

I have an OOP question about polymorphism I was hoping someone could help me with.

Basically i’m wondering what the advantage of using an Interface is over calling a function from the constructor, for example how is this:


package {
	public class Thing {
		public function Thing() {
			init();
		}
		
		private function init():void {
		}
	}
}

different from:


package {
	public class Thing implements init {
		public function Thing() {
		}
		
		private function init():void {
		}
	}
}

package {
	public interface init {
		function init();
	}
}