Inner and Nested Classes: Nested 1

/**
 *  This code is from the book:
 *  Winder, R and Roberts, G (1998)
 *  Developing Java Software</em>
 *  John Wiley & Sons.
 *  It is copyright (c) 1997 Russel Winder
 *  and Graham Roberts.
 */

import java.util.Vector;

class StringCounter
{
  private static class CountedString
  {
    public CountedString(String s)
    {
      item = s;
    }
    String item;
    int count = 1;
  }

  // If the String argument already exists, 
  // increment the count. Otherwise add a 
  // new CountedString with a count of 1
  public void addString(String s)
  {
    CountedString tmp = searchFor(s);
    if (tmp == null)
    {
      items.addElement(new CountedString(s));
    }
    else
    {
      tmp.count++;
    }
  }

  // Return the number of times a string has been added
  public int getCount(String s)
  {
    CountedString tmp = searchFor(s);
    return tmp == null ? 0 : tmp.count;
  }

  // Private helper method.
  // If a string has already been added, 
  // return its CountedString
  // object, otherwise return null.
  private CountedString searchFor(String s)
  {
    for (int i = 0; i < items.size(); i++)
    {
      CountedString tmp = 
        (CountedString)items.elementAt(i);
      if ((tmp.item).equals(s))
        return tmp;
    }
    return null;
  }

  public static void main(String[] args)
  {
    Class3 c3 = new Class3();
    c3.addString("hello");
    c3.addString("world");
    c3.addString("world");
    c3.addString("hello");
    c3.addString("hello");
    c3.addString("world");
    c3.addString("hello");
    c3.addString("world");
    c3.addString("hello");
    c3.addString("hello");
    c3.addString("world");
    c3.addString("world");

    System.out.println("hello as been added " +
        	  c3.getCount("hello") + " times");
    System.out.println("world as been added " +
              c3.getCount("world") + " times");
    System.out.println("Hello as been added " +
              c3.getCount("Hello") + " times");

  }

  private Vector items = new Vector();
}