| /* |
| * Copyright (C) 2015 The Dagger Authors. |
| * |
| * Licensed 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. |
| */ |
| |
| package dagger.functional.cycle; |
| |
| import static com.google.common.truth.Truth.assertThat; |
| import static java.lang.Thread.State.BLOCKED; |
| import static java.lang.Thread.State.WAITING; |
| import static java.lang.annotation.RetentionPolicy.RUNTIME; |
| import static org.junit.Assert.fail; |
| |
| import com.google.common.util.concurrent.SettableFuture; |
| import com.google.common.util.concurrent.Uninterruptibles; |
| import dagger.Component; |
| import dagger.Module; |
| import dagger.Provides; |
| import java.lang.annotation.Retention; |
| import java.util.ArrayList; |
| import java.util.Collections; |
| import java.util.List; |
| import java.util.concurrent.CountDownLatch; |
| import java.util.concurrent.ExecutionException; |
| import java.util.concurrent.atomic.AtomicInteger; |
| import javax.inject.Provider; |
| import javax.inject.Qualifier; |
| import javax.inject.Singleton; |
| import org.junit.Test; |
| import org.junit.runner.RunWith; |
| import org.junit.runners.JUnit4; |
| |
| @RunWith(JUnit4.class) |
| public class DoubleCheckCycleTest { |
| // TODO(b/77916397): Migrate remaining tests in DoubleCheckTest to functional tests in this class. |
| |
| /** A qualifier for a reentrant scoped binding. */ |
| @Retention(RUNTIME) |
| @Qualifier |
| @interface Reentrant {} |
| |
| /** A module to be overridden in each test. */ |
| @Module |
| static class OverrideModule { |
| @Provides |
| @Singleton |
| Object provideObject() { |
| throw new IllegalStateException("This method should be overridden in tests"); |
| } |
| |
| @Provides |
| @Singleton |
| @Reentrant |
| Object provideReentrantObject(@Reentrant Provider<Object> provider) { |
| throw new IllegalStateException("This method should be overridden in tests"); |
| } |
| } |
| |
| @Singleton |
| @Component(modules = OverrideModule.class) |
| interface TestComponent { |
| Object getObject(); |
| @Reentrant Object getReentrantObject(); |
| } |
| |
| @Test |
| public void testNonReentrant() { |
| AtomicInteger callCount = new AtomicInteger(0); |
| |
| // Provides a non-reentrant binding. The provides method should only be called once. |
| DoubleCheckCycleTest.TestComponent component = |
| DaggerDoubleCheckCycleTest_TestComponent.builder() |
| .overrideModule( |
| new OverrideModule() { |
| @Override Object provideObject() { |
| callCount.getAndIncrement(); |
| return new Object(); |
| } |
| }) |
| .build(); |
| |
| assertThat(callCount.get()).isEqualTo(0); |
| Object first = component.getObject(); |
| assertThat(callCount.get()).isEqualTo(1); |
| Object second = component.getObject(); |
| assertThat(callCount.get()).isEqualTo(1); |
| assertThat(first).isSameInstanceAs(second); |
| } |
| |
| @Test |
| public void testReentrant() { |
| AtomicInteger callCount = new AtomicInteger(0); |
| |
| // Provides a reentrant binding. Even though it's scoped, the provides method is called twice. |
| // In this case, we allow it since the same instance is returned on the second call. |
| DoubleCheckCycleTest.TestComponent component = |
| DaggerDoubleCheckCycleTest_TestComponent.builder() |
| .overrideModule( |
| new OverrideModule() { |
| @Override Object provideReentrantObject(Provider<Object> provider) { |
| if (callCount.incrementAndGet() == 1) { |
| return provider.get(); |
| } |
| return new Object(); |
| } |
| }) |
| .build(); |
| |
| assertThat(callCount.get()).isEqualTo(0); |
| Object first = component.getReentrantObject(); |
| assertThat(callCount.get()).isEqualTo(2); |
| Object second = component.getReentrantObject(); |
| assertThat(callCount.get()).isEqualTo(2); |
| assertThat(first).isSameInstanceAs(second); |
| } |
| |
| @Test |
| public void testFailingReentrant() { |
| AtomicInteger callCount = new AtomicInteger(0); |
| |
| // Provides a failing reentrant binding. Even though it's scoped, the provides method is called |
| // twice. In this case we throw an exception since a different instance is provided on the |
| // second call. |
| DoubleCheckCycleTest.TestComponent component = |
| DaggerDoubleCheckCycleTest_TestComponent.builder() |
| .overrideModule( |
| new OverrideModule() { |
| @Override Object provideReentrantObject(Provider<Object> provider) { |
| if (callCount.incrementAndGet() == 1) { |
| provider.get(); |
| return new Object(); |
| } |
| return new Object(); |
| } |
| }) |
| .build(); |
| |
| assertThat(callCount.get()).isEqualTo(0); |
| try { |
| component.getReentrantObject(); |
| fail("Expected IllegalStateException"); |
| } catch (IllegalStateException e) { |
| assertThat(e).hasMessageThat().contains("Scoped provider was invoked recursively"); |
| } |
| assertThat(callCount.get()).isEqualTo(2); |
| } |
| |
| @Test(timeout = 5000) |
| |
| public void testGetFromMultipleThreads() throws Exception { |
| AtomicInteger callCount = new AtomicInteger(0); |
| AtomicInteger requestCount = new AtomicInteger(0); |
| SettableFuture<Object> future = SettableFuture.create(); |
| |
| // Provides a non-reentrant binding. In this case, we return a SettableFuture so that we can |
| // control when the provides method returns. |
| DoubleCheckCycleTest.TestComponent component = |
| DaggerDoubleCheckCycleTest_TestComponent.builder() |
| .overrideModule( |
| new OverrideModule() { |
| @Override |
| Object provideObject() { |
| callCount.incrementAndGet(); |
| try { |
| return Uninterruptibles.getUninterruptibly(future); |
| } catch (ExecutionException e) { |
| throw new RuntimeException(e); |
| } |
| } |
| }) |
| .build(); |
| |
| |
| int numThreads = 10; |
| CountDownLatch remainingTasks = new CountDownLatch(numThreads); |
| List<Thread> tasks = new ArrayList<>(numThreads); |
| List<Object> values = Collections.synchronizedList(new ArrayList<>(numThreads)); |
| |
| // Set up multiple threads that call component.getObject(). |
| for (int i = 0; i < numThreads; i++) { |
| tasks.add( |
| new Thread( |
| () -> { |
| requestCount.incrementAndGet(); |
| values.add(component.getObject()); |
| remainingTasks.countDown(); |
| })); |
| } |
| |
| // Check initial conditions |
| assertThat(remainingTasks.getCount()).isEqualTo(10); |
| assertThat(requestCount.get()).isEqualTo(0); |
| assertThat(callCount.get()).isEqualTo(0); |
| assertThat(values).isEmpty(); |
| |
| // Start all threads |
| tasks.forEach(Thread::start); |
| |
| // Wait for all threads to wait/block. |
| long waiting = 0; |
| while (waiting != numThreads) { |
| waiting = |
| tasks.stream() |
| .map(Thread::getState) |
| .filter(state -> state == WAITING || state == BLOCKED) |
| .count(); |
| } |
| |
| // Check the intermediate state conditions. |
| // * All 10 threads should have requested the binding, but none should have finished. |
| // * Only 1 thread should have reached the provides method. |
| // * None of the threads should have set a value (since they are waiting for future to be set). |
| assertThat(remainingTasks.getCount()).isEqualTo(10); |
| assertThat(requestCount.get()).isEqualTo(10); |
| assertThat(callCount.get()).isEqualTo(1); |
| assertThat(values).isEmpty(); |
| |
| // Set the future and wait on all remaining threads to finish. |
| Object futureValue = new Object(); |
| future.set(futureValue); |
| remainingTasks.await(); |
| |
| // Check the final state conditions. |
| // All values should be set now, and they should all be equal to the same instance. |
| assertThat(remainingTasks.getCount()).isEqualTo(0); |
| assertThat(requestCount.get()).isEqualTo(10); |
| assertThat(callCount.get()).isEqualTo(1); |
| assertThat(values).isEqualTo(Collections.nCopies(numThreads, futureValue)); |
| } |
| } |