package org.apidesign.openfixed;

 import java.util.List;

 import java.util.concurrent.CountDownLatch;

 /** Test the Calculator.createPending() behavior.

  *

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

  */

 public class PendingTest extends CalculatorBase {

     public PendingTest(String testName) {

         super(testName);

     }

     @Override

     protected Calculator create() {

         return Calculator.createPending();

     }

     public void testPendingEvents() throws Exception {

         BlockingListener bl = new BlockingListener();

         Calculator calc = create();

         calc.addModificationListener(bl);

         calc.add(10);

         bl.first.await();

         calc.add(1);

         calc.add(2);

         calc.add(3);

         bl.cdl.countDown();

         List<ModificationEvent> events = bl.assertEvents("Four changes together", 4);

         assertEquals("No pending events for first event", 0, events.get(0).getPending());

         assertEquals("Group of three, two remaining", 2, events.get(1).getPending());

         assertEquals("Group of three, one remaining", 1, events.get(2).getPending());

         assertEquals("Group of three, last one", 0, events.get(3).getPending());

     }

     static class BlockingListener extends MockListener {

         CountDownLatch first = new CountDownLatch(1);

         CountDownLatch cdl = new CountDownLatch(1);

         @Override

         public synchronized void modification(ModificationEvent ev) {

             try {

                 first.countDown();

                 cdl.await();

             } catch (InterruptedException ex) {

                 throw new IllegalStateException(ex);

             }

             super.modification(ev);

         }

     }

 }