CollectiveHealth-gists

public class ComputerTestUsingSetter {

    @Test
    public void testPlayVideo() {
        Computer computer = new Computer();
        MotherBoard motherBoard = new MotherBoard();
        SoundCard soundCard = new SoundCard();
        VideoCard videoCard = new VideoCard();
        SoundSystem soundSystem = Mockito.mock(SoundSystem.class);
        DisplaySystem displaySystem = Mockito.mock(DisplaySystem.class);

CollectiveHealth-gists

public class ComputerTestUsingTestModule {

    @Test
    public void testPlayVideo() {
        Injector injector = Guice.createInjector(new TestModule()
                .withMockedClasses(SoundSystem.class, DisplaySystem.class));

        Computer computer = injector.getInstance(Computer.class);
        SoundSystem soundSystem = injector.getInstance(SoundSystem.class);
        DisplaySystem displaySystem = injector.getInstance(DisplaySystem.class);

CollectiveHealth-gists

public class ComputerTestModule extends TestModule {

    @Override
    protected Collection<ClassInstancePair<?>> getDefaultInstances() {
        return Arrays.asList(
                createClassMockPair(DisplaySystem.class),
                createClassMockPair(SoundSystem.class));
    }

}

CollectiveHealth-gists

public class IntegrationWithDisplaySystemTest {

    @Test
    public void testDisplaySystem() {
        Injector injector = Guice.createInjector(new ComputerTestModule()
                .withInstance(DisplaySystem.class, new DisplaySystem()));

        Computer computer = injector.getInstance(Computer.class);

        // We are satisfied with no exception being thrown

CollectiveHealth-gists

public class IntegrationWithSoundSystemTest {

    @Test
    public void testSoundSystem() {
        Injector injector = Guice.createInjector(new ComputerTestModule()
                .withInstance(SoundSystem.class, new SoundSystem()));

        Computer computer = injector.getInstance(Computer.class);

        // We will be satisfied with no exception being thrown