Exercise 2        Name __________________        Score __/24

1. (10) Sketch object diagrams for B and C similar to at right:

   1. ArrayList B = new ArrayList();
      B.add("apples");
      B.add("oranges");
      B.add("durian");
      B.remove(1);
      B.add("grapes");

   2. Use the TicketMachine definition below; a typical object diagram is at right.

      TicketMachine t1 = new TicketMachine(40);
      TicketMachine t2 = new TicketMachine(50);
      TicketMachine t3 = new TicketMachine(60);

      ArrayList C = new ArrayList();
      C.add(t1);
      C.add(t2);
      C.add(t3); 
      C.remove(0);

   public class TicketMachine  {  private int price;  private int balance;  private int total;  public TicketMachine(int ticketCost)  {        price = ticketCost;        balance = 0;        total = 0;  }  }

   
    

2. (4) From Question 1 what is:
   1. B.size()
   2. C.size()
   3. B.get(1)
   4. C.get(1)

    

3. (10) From Question 1, what is:
    
   1. int i = 0;
      while (i < 5) {
          System.out.println(i);
          i = i + 1;
      }
       
   2. int i = 5;
      while (i > 0) {
          System.out.println(i);
          i = i - 1;
      }
       
   3. int i = 0;
      while (i < B.size() ) {
          System.out.println( B.get(i) );
          i = i + 1;
      }
       
   4. int i = B.size();
      while (i > 0 ) {
           i = i - 1;
          System.out.println( B.get(i) );
      }
       
   5. Iterator it = B.iterator();
      while (it.hasNext() ) {
          System.out.println( it.next() );
      }