/*

  * To change this template, choose Tools | Templates

  * and open the template in the editor.

  */

 package org.apidesign.codeinjection;

 import java.util.Iterator;

 import java.util.ServiceLoader;

 import org.apidesign.codeinjection.spi.CountDownExtender;

 /** Second version to {@link CountDownImplV1} - imagine someone wants to

  * reimplement {@link #down()} method to decrement by two not just by one.

  * You do not like that idea at all, but you do not want to prevent such

  * behaviour. You just do not want to maintain such bloody code. What can

  * you do? You need to allow <b>code injection</b> via the

  * {@link CountDownExtender} class!

  *

  * @author Jaroslav Tulach <jtulach@netbeans.org>

  */

 final class CountDownImplV2 extends CountDown {

     private int cnt;

     CountDownImplV2(int initial) {

         this.cnt = initial;

     }

 // BEGIN: codeinjection.v2

     public void down() {

         Iterator<CountDownExtender> it =

             ServiceLoader.load(CountDownExtender.class).iterator();

         if (it.hasNext()) {

             // injected behaviour

             cnt = it.next().decrement(cnt);

         } else {

             // common behaviour of 1.0 version

             cnt--;

         }

     }

     public boolean isDown() {

         return cnt <= 0;

     }

 // END: codeinjection.v2

 }