package org.apache.onami.persist;
/*
* 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 org.junit.Before;
import org.junit.Test;
import org.mockito.invocation.InvocationOnMock;
import org.mockito.stubbing.Answer;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import java.util.concurrent.CountDownLatch;
import static org.hamcrest.CoreMatchers.is;
import static org.junit.Assert.assertThat;
import static org.junit.Assert.assertTrue;
import static org.mockito.Mockito.*;
/**
* Test for {@link org.apache.onami.persist.EntityManagerProviderImpl}.
* This class tests the behavior of the impl in the context of multiple threads.
*/
public class EntityManagerProviderImplThreadingTest
{
private EntityManagerProviderImpl sut;
private EntityManagerFactory emf;
@Before
public void setUp()
{
// input
final EntityManagerFactoryProvider emfProvider = mock( EntityManagerFactoryProvider.class );
// subject under test
sut = new EntityManagerProviderImpl( emfProvider, null );
// helpers
emf = mock( EntityManagerFactory.class );
doReturn( emf ).when( emfProvider ).get();
doAnswer( new Answer()
{
public Object answer( InvocationOnMock invocation )
throws Throwable
{
return mock( EntityManager.class );
}
} ).when( emf ).createEntityManager();
}
@Test
public void beginShouldBeCallableFromMultipleThreads()
{
for ( int i = 0; i < 5; i++ )
{
new Thread( new Runnable()
{
public void run()
{
assertThat( sut.isActive(), is( false ) );
sut.begin();
assertThat( sut.isActive(), is( true ) );
}
} ).start();
}
}
@Test
public void getShouldReturnTheSameInstanceInTheSameThread()
throws Exception
{
final int numThreads = 5;
final CountDownLatch latch = new CountDownLatch( numThreads );
for ( int i = 0; i < numThreads; i++ )
{
new Thread( new Runnable()
{
public void run()
{
sut.begin();
final EntityManager em1 = sut.get();
final EntityManager em2 = sut.get();
final EntityManager em3 = sut.get();
final EntityManager em4 = sut.get();
latch.countDown();
assertTrue( em1 == em2 );
assertTrue( em1 == em3 );
assertTrue( em1 == em4 );
}
} ).start();
}
latch.await();
verify( emf, times( numThreads ) ).createEntityManager();
}
}