//: c08:CatsAndDogs2.java
// From Thinking in Java, 2nd Edition
// Available at http://www.BruceEckel.com
// (c) Bruce Eckel 1999
// Copyright notice in Copyright.txt
// Simple collection with Iterator
import java.util.*;

class Cat2 {
  private int catNumber;
  Cat2(int i) {
    catNumber = i;
  }
  void print() {
    System.out.println("Cat number " +catNumber);
  }
}

class Dog2 {
  private int dogNumber;
  Dog2(int i) {
    dogNumber = i;
  }
  void print() {
    System.out.println("Dog number " +dogNumber);
  }
}

public class CatsAndDogs2 {
  public static void main(String[] args) {
    ArrayList cats = new ArrayList();
    for(int i = 0; i < 7; i++)
      cats.add(new Cat2(i));
    // Not a problem to add a dog to cats:
    cats.add(new Dog2(7));
    Iterator e = cats.iterator();
    while(e.hasNext())
      ((Cat2)e.next()).print();
    // Dog is detected only at run-time
  }
} ///:~