package org.apidesign.component;

 import java.util.Iterator;

 import org.junit.BeforeClass;

 import org.junit.Test;

 import org.netbeans.junit.MockServices;

 import org.openide.util.Lookup;

 import static org.junit.Assert.*;

 import org.openide.util.Lookup.Result;

 import org.openide.util.LookupEvent;

 import org.openide.util.LookupListener;

 public class InjectionSlotChangesTest {

     public InjectionSlotChangesTest() {

     }

     @BeforeClass

     public static void setUpClass() throws Exception {

         // this is a support for "dynamic" registration of any class

         // into the global pool of Lookup.getDefault() and java.util.ServiceLoader

         // either in @BeforeClass or @Before register 

         // classes of the mock instances that you want your code 

         // to find

         MockServices.setServices(ImplOne.class, ImplTwo.class);

     }

     @Test

     public void multiSlot() {

         Iterator<? extends InjectionSlot> it = InjectionSlot.multiSlot().iterator();

         assertTrue("Has at least one", it.hasNext());

         assertEquals("The first is ImplOne", ImplOne.class, it.next().getClass());

         assertTrue("Has two", it.hasNext());

         assertEquals("The second is ImplTwo", ImplTwo.class, it.next().getClass());

         assertFalse("No other instance registered", it.hasNext());

         // BEGIN: lookup.listener

         class Listener implements LookupListener {

             int cnt;

             public void resultChanged(LookupEvent arg0) {

                 cnt++;

             }

         }

         Listener listener = new Listener();

         Lookup.Result<InjectionSlot> res = 

             Lookup.getDefault().lookupResult(InjectionSlot.class);

         res.addLookupListener(listener);

         assertEquals("Two services now", 2, res.allInstances().size());

         MockServices.setServices(ImplTwo.class);

         assertEquals("One service only", 1, res.allInstances().size());

         assertEquals("One change in listener", 1, listener.cnt);

         assertEquals(

             "The second is ImplTwo", 

             ImplTwo.class, 

             res.allInstances().iterator().next().getClass()

         );

         // END: lookup.listener

     }

     public static final class ImplOne extends InjectionSlot {

     }

     public static final class ImplTwo extends InjectionSlot {

     }

 }