/* An instance of this class, which is a child of TossableCoin,
** represents a coin that can be tossed (resulting in either HEADS
** or TAILS).  The new functionality here is that a coin is able to
** report how many tosses resulted in HEADS, in TAILS, and in total.
*/
public class TossableCoinWithCounts extends TossableCoin {

   // instance variables
   // -------------------
   
   private int headsCount, tailsCount; 

   // constructor
   // -----------
   
   public TossableCoinWithCounts() {
      super();   // call the parent class's constructor.  Which is 
                 // not necessary, as this call is done by default anyway.
                 // 
      headsCount = 0;  // not necessary, as numeric instance variables
      tailsCount = 0;  // are automatically initialized to zero
   }

   // observers
   // ----------
   
   /* Returns the # of times that this coin has been tossed.
   */
   public int numTosses() { return headsCount + tailsCount; }
   
   /* Returns the # of times that a toss of this coin resulted in HEADS.
   ** result of HEADS. 
   */
   public int numHeads() { return headsCount; }
   
   /* Returns the # of times that a toss of this coin resulted in TAILS.
   */
   public int numTails() { return tailsCount; }

   @Override
   public String toString() {
      return super.toString() +
             " (# HEADS:" + numHeads() +
             "; # TAILS:" + numTails() + ")"; 
   }
   

   // mutators
   // --------
   
   @Override    // signals that this method overrides an inherited one
   public void toss() { 
      super.toss();   // invoke the overridden method in parent class
      if (isHeads()) 
         { headsCount++; }
      else 
         { tailsCount++; }
      // Note that because the inherited instance variable (headsShowing) 
      // is declared to be private in the parent class, it cannot be
      // referred to here.
   }



   // ---------------------------------------------------------
   /* main() method, strictly for testing purposes
   */
   public static void main(String[] args) {
      TossableCoinWithCounts coin = new TossableCoinWithCounts();
      System.out.println("Initially: " + coin);
      for (int i=0; i != 10; i++) {
         coin.toss();
         System.out.println(coin);
      }
   }
}