package org.apache.onami.scopes;
   
   /*
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you under the Apache License, Version 2.0 (the
    * "License"); you may not use this file except in compliance
   * with the License.  You may obtain a copy of the License at
   *
   *   http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing,
   * software distributed under the License is distributed on an
   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   * KIND, either express or implied.  See the License for the
   * specific language governing permissions and limitations
   * under the License.
   */
  
  import static org.junit.Assert.assertEquals;
  import static org.junit.Assert.assertSame;
  
  import java.util.concurrent.Callable;
  import java.util.concurrent.CountDownLatch;
  import java.util.concurrent.ExecutorService;
  import java.util.concurrent.Executors;
  
  import org.apache.onami.lifecycle.standard.AfterInjectionModule;
  import org.apache.onami.test.OnamiRunner;
  import org.junit.Before;
  import org.junit.Test;
  import org.junit.runner.RunWith;
  
  import com.google.inject.Guice;
  import com.google.inject.Inject;
  import com.google.inject.Injector;
  import com.google.inject.Provider;
  
  @RunWith(OnamiRunner.class)
  public class TestConcurrentLazySingleton
  {
      public static class InjectedAnnotatedProvider
      {
          public final Provider<AnnotatedConcurrentLazySingletonObject> provider;
  
          @Inject
          public InjectedAnnotatedProvider( Provider<AnnotatedConcurrentLazySingletonObject> provider )
          {
              this.provider = provider;
          }
      }
  
      @Before
      public void setup()
      {
          AnnotatedConcurrentLazySingletonObject.constructorCount.set( 0 );
          AnnotatedConcurrentLazySingletonObject.postConstructCount.set( 0 );
          LazySingletonObject.constructorCount.set( 0 );
          LazySingletonObject.postConstructCount.set( 0 );
      }
  
      @ConcurrentLazySingleton
      public static class DeadLockTester
      {
          @Inject
          public DeadLockTester( final Injector injector )
              throws InterruptedException
          {
              final CountDownLatch latch = new CountDownLatch( 1 );
              ExecutorService executorService = Executors.newSingleThreadExecutor();
              try
              {
                  executorService.submit( new Callable<Object>()
                  {
                      public Object call()
                          throws Exception
                      {
                          injector.getInstance( AnnotatedConcurrentLazySingletonObject.class );
                          latch.countDown();
                          return null;
                      }
                  } );
                  latch.await();
              }
              finally
              {
                  executorService.shutdownNow();
              }
          }
      }
  
      @Test
      public void testDeadLock()
          throws InterruptedException
      {
          Injector injector = Guice.createInjector( new ScopesModule() );
          injector.getInstance( DeadLockTester.class ); // if ConcurrentLazySingleton is not used, this line will deadlock
         assertEquals( AnnotatedConcurrentLazySingletonObject.constructorCount.get(), 1 );
     }
 
     @Test
     public void testUsingAnnotation()
     {
         Injector injector = Guice.createInjector( new AfterInjectionModule(), new ScopesModule() );
 
         assertEquals( AnnotatedConcurrentLazySingletonObject.constructorCount.get(), 0 );
         assertEquals( AnnotatedConcurrentLazySingletonObject.postConstructCount.get(), 0 );
 
         AnnotatedConcurrentLazySingletonObject instance =
             injector.getInstance( AnnotatedConcurrentLazySingletonObject.class );
         assertEquals( AnnotatedConcurrentLazySingletonObject.constructorCount.get(), 1 );
         assertEquals( AnnotatedConcurrentLazySingletonObject.postConstructCount.get(), 1 );
 
         AnnotatedConcurrentLazySingletonObject instance2 =
             injector.getInstance( AnnotatedConcurrentLazySingletonObject.class );
         assertEquals( AnnotatedConcurrentLazySingletonObject.constructorCount.get(), 1 );
         assertEquals( AnnotatedConcurrentLazySingletonObject.postConstructCount.get(), 1 );
 
         assertSame( instance, instance2 );
     }
 
     @Test
     public void testUsingInWithProviderAndAnnotation()
     {
         Injector injector = Guice.createInjector( new AfterInjectionModule(), new ScopesModule() );
 
         assertEquals( AnnotatedConcurrentLazySingletonObject.constructorCount.get(), 0 );
         assertEquals( AnnotatedConcurrentLazySingletonObject.postConstructCount.get(), 0 );
 
         InjectedAnnotatedProvider injectedProvider = injector.getInstance( InjectedAnnotatedProvider.class );
         assertEquals( AnnotatedConcurrentLazySingletonObject.constructorCount.get(), 0 );
         assertEquals( AnnotatedConcurrentLazySingletonObject.postConstructCount.get(), 0 );
 
         AnnotatedConcurrentLazySingletonObject instance = injectedProvider.provider.get();
         assertEquals( AnnotatedConcurrentLazySingletonObject.constructorCount.get(), 1 );
         assertEquals( AnnotatedConcurrentLazySingletonObject.postConstructCount.get(), 1 );
 
         AnnotatedConcurrentLazySingletonObject instance2 = injectedProvider.provider.get();
         assertEquals( AnnotatedConcurrentLazySingletonObject.constructorCount.get(), 1 );
         assertEquals( AnnotatedConcurrentLazySingletonObject.postConstructCount.get(), 1 );
 
         assertSame( instance, instance2 );
     }
 }