//amb.java --- demostrate Inheritance and Polymorphism. Also show you
//..how to do Runtime type checking. @CopyLeft by tsaiwn@csie.nctu.edu.tw
import java.awt.*;
public class amb extends MyApplet {   public static final int N_OBJ = 3;
      static Frame f = new Frame(" <<< Polymorphism >>> ");
   public static void main(String[ ] args) {
      Animal a[ ] = new Animal[N_OBJ];
       a[0] = new Animal(1);
       a[1] = new Cat(2);  a[2] = new Mankind(3);
      for(int i = 0; i< N_OBJ ; ++i) a[i].init( );   // Polymorphism
      for(int i = 0; i < N_OBJ; ++i) {
         showMessage(a[i]);
         f.add(a[i]); f.setSize(300,300); f.validate( ); f.setVisible(true);
         // Polymorphism
         a[i].talk( );
         try { Thread.sleep(568); } catch (Exception e) { }
         print("Hit Return ...");
         int c=0; try{ c=System.in.read();} catch (Exception e) { }
         if(c!=13) try{ c=System.in.read();} catch (Exception e) { }
         if( i < N_OBJ -1 ) f.remove(a[i]); println("");
      }
      newPlayFile("bye.au");
      try { Thread.sleep(988); } catch (Exception e) { }
      System.exit(0);
   }
   static void showMessage(Object o) {  // 由 Object 決定秀啥 message
      f.setTitle(""+o);
      if(o instanceof Mankind) print("Mankind talking...");
      else if(o instanceof Cat ) print("Cat talking...");
      else if(o instanceof Animal) print("Animal talking...");
   }
} // class amb
class Animal extends MyApplet {    // Animal is-a MyApplet (is-a Applet)
   protected int n = 0;
   public Animal(int n) { this.n = n; }
   void talk( ) {
      for(int i=1; i <= n; ++i) { beep(); newPlayFile("chichi.au"); }
   }
}
class Cat extends Animal {
   public Cat(int n) { super(n); }
   public void init ( ) {
      PicturePanel p = new PicturePanel("images/cat.gif", true);
      Panel p23 = new Panel(new GridLayout(2,1));
      PicturePanel p2a = new PicturePanel("images/cat1.gif", false);
      PicturePanel p2b = new PicturePanel("images/cat2.gif", false);
      p23.add(p2a); p23.add(p2b);
      setLayout( new GridLayout(1,2));    // Layout of this Cat
      add(p); add(p23);     // put p and p23 into the Cat (is an Applet too)
   }
   void talk( ) { for(int i=1; i <= n; ++i) newPlayFile("meow.wav"); }
} // Cat
class Mankind extends Animal {
   public Mankind(int n) { super(n); } 
   public void init ( ) {
      PicturePanel p = new PicturePanel("images/mypic.jpg", true);
      setLayout( new GridLayout(1,1)); add(p);
   } // init
   void talk( ) { // new talk( ) for Mankind, 若不寫, 則會用原先 Animal 的 talk
      for(int i=1; i <= n; ++i) {
         newPlayFile("yahoo.au"); 
         try { Thread.sleep(358); } catch (Exception e) { }
      }
   } // talk
   void talk(String what) { newPlayFile(what); }  // talk(String)
} // class Mankind