// Film.java =========================================
class Film extends InventoryItem implements Sortable
{
   public Film(int i, int rTemp) 
   {
       super("The Film class",i);
       recommendedTemp = rTemp;
       numberOfExposures = 24;
   } // constructor

   // methods speific to Film
   void print()
   {
       System.out.println( getDescription() + getId() + " : " + getQuantityOnHand());
       System.out.println( " recom. temp : " + recommendedTemp);
   } // print

   public int compare(Sortable b) // implements the interface
   {
      Film fm = (Film)b;   // cast b to Film
      return recommendedTemp - fm.recommendedTemp;
   } // compare

   private int recommendedTemp;
   private int numberOfExposures;
} // Film

// InventoryItem.java =========================================
abstract class InventoryItem
{
   public InventoryItem(String desc, int id) 
   {
       description = desc;
       quantityOnHand = 0;
       inventoryNumber = id;
       price = 0;
   } // constructor

   abstract void print();

   public String getDescription() { return description;}
   public String getId() { return " " + inventoryNumber + " ";}
   public int getQuantityOnHand() { return quantityOnHand;}
   public int getInventoryID() { return inventoryNumber;}
   public double getPrice() { return price;}

   private String description;
   private int quantityOnHand;
   private int inventoryNumber;
   private double price;
} // class InventoryItem

// Sort.java =========================================
import java.util.*;

public class Sort
{   
   public static void sort(Vector a)
   {
      int k;
      int n = a.size();
      k = 0;
      while (k < n)
      {
         int j = getSmallest(a, k);
         exchange(a, k, j);
         k ++;
      } // while
   } // Sort
 
   static void exchange(Vector a, int k, int j)
   {
      Object temp;

      temp = a.elementAt(k);
      a.setElementAt(a.elementAt(j), k);
      a.setElementAt(temp, j);
   } // exchange

   static int getSmallest(Vector a, int k)
   {
      Sortable s = (Sortable)a.elementAt(k);
      int n = a.size();
      int minLoc = k;
      for (int i = k; i < n; i ++)
         if (s.compare((Sortable)a.elementAt(i)) > 0)  // s > a[i]
         {
            s = (Sortable)a.elementAt(i);
            minLoc = i;
         }
       return minLoc;
   } // getSmallest
} // Sort


// Sortable.java =========================================
public interface Sortable
{
   public abstract int compare(Sortable b);  // child class will implement it
}