package apipkg;

 import implpkg.Accessor;

 import javax.swing.event.ChangeEvent;

 import javax.swing.event.ChangeListener;

 /** Class in API that everyone can use.

  *

  * @author Jaroslav Tulach

  */

 // BEGIN: design.less.friend.Item

 public final class Item {

     private int value;

     private ChangeListener listener;

     // BEGIN: design.less.friend.Item.static

     static {

         Accessor.setDefault(new AccessorImpl());

     }

     // END: design.less.friend.Item.static

     /** Contructor for friends */

     Item() {

     }

     /** Anyone can value of the item. At least if it 

      * can get a reference to it.

      */

     public void setValue(int x) {

         value = x;

         ChangeListener l = listener;

         if (l != null) {

             l.stateChanged(new ChangeEvent(this));

         }

     }

     /** Anyone can get the value of the item. 

      */

     public int getValue() {

         return value;

     }

     /** Only the impl package can listen.

      */

     void addChangeListener(ChangeListener l) {

         assert listener == null;

         listener = l;

     }

 }

 // END: design.less.friend.Item