1: //JekyllAndHyde.java 3: import java.util.Observable; 5: public class JekyllAndHyde 6: extends Observable 7: { 8: private String name; 10: //Constructor 11: JekyllAndHyde() 12: { 13: name = "Dr. Jekyll"; 14: } 16: public void drinkPotion() 17: { 18: name = "Mr.Hyde"; 19: setChanged(); 20: notifyObservers(); 21: } 23: public String getName() 24: { 25: return name; 26: } 27: }