Add Spring 3.0.0 java based IOC to JUnit 4.7 tests

Question

There is a doc http://static.springsource.org/spring/docs/2.5.6/reference/testing.html how to add IoC support to junit tests using xml-configuration, but I can not find example for java-based configuration...

For example, I have java-based bean:

public class AppConfig
{
    @Bean
    public Test getTest() { return new Test(); }
}

And test:

@RunWith(SpringJUnit4ClassRunner.class)
public class IocTest
{
    @Autowired
    private Test test;

    @Test
    public void testIoc()
    {
        Assert.assertNotNull(test);
    }
}

What should I add to enable java-based beans to my junit test without using xml-configs?

Normally I use:

new AnnotationConfigApplicationContext(AppConfig.class);

but it does not work for tests...

Answer 1

If you are getting a null value probably it's not loading the application context.

Note that by default it the runner loads it from "classpath:/com/test/IocTest-context.xml" (assuming IocTest.java package is the com.test)

If it is not there try specifying it by adding

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = { "PATH_TO_YOUR_APP_CONTEXT/yourApplicationContext.xml" })
public class IocTest
{
    @Autowired
    private Test test;

    @Test
    public void testIoc()
    {
        Assert.notNull("test is null", test);
    }
}

Answer 2

Genereally, why this does not work (assert fails):

public class IocTest
{
    @BeforeClass
    public static void initSpringIoc()
    {
        AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext(ApplicationConfig.class);
        NotExistsPredicate predicate = ctx.getBean(NotExistsPredicate.class);
        LoggerFactory.getLogger(IocTest.class).debug(predicate.toString());
    }

    @Test
    public void testIoc()
    {
        TestService service = new TestService();
        Assert.assertNotNull(service.getPredicate()); // assert fails
    }
}

public class TestService
{
    @Autowired
    private NotExistsPredicate predicate;

    public NotExistsPredicate getPredicate()
    {
        return predicate;
    }
}

Log output:

1    [main] INFO  org.springframework.context.annotation.AnnotationConfigApplicationContext  - Refreshing org.springframework.context.annotation.AnnotationConfigApplicationContext@e94e92: startup date [Tue Feb 09 15:32:48 EET 2010]; root of context hierarchy
2    [main] DEBUG org.springframework.context.annotation.AnnotationConfigApplicationContext  - Bean factory for org.springframework.context.annotation.AnnotationConfigApplicationContext@e94e92: org.springframework.beans.factory.support.DefaultListableBeanFactory@a37368: defining beans [org.springframework.context.annotation.internalConfigurationAnnotationProcessor,org.springframework.context.annotation.internalAutowiredAnnotationProcessor,org.springframework.context.annotation.internalRequiredAnnotationProcessor,org.springframework.context.annotation.internalCommonAnnotationProcessor,applicationConfig]; root of factory hierarchy
33   [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory  - Creating shared instance of singleton bean 'org.springframework.context.annotation.internalConfigurationAnnotationProcessor'
33   [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory  - Creating instance of bean 'org.springframework.context.annotation.internalConfigurationAnnotationProcessor'
84   [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory  - Eagerly caching bean 'org.springframework.context.annotation.internalConfigurationAnnotationProcessor' to allow for resolving potential circular references
87   [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory  - Finished creating instance of bean 'org.springframework.context.annotation.internalConfigurationAnnotationProcessor'
129  [main] DEBUG org.springframework.context.annotation.ConfigurationClassBeanDefinitionReader  - Registering bean definition for @Bean method com.mihailenco.config.ApplicationConfig.getNotExistsPredicate()
133  [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory  - Creating shared instance of singleton bean 'org.springframework.context.annotation.internalAutowiredAnnotationProcessor'
133  [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory  - Creating instance of bean 'org.springframework.context.annotation.internalAutowiredAnnotationProcessor'
135  [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory  - Eagerly caching bean 'org.springframework.context.annotation.internalAutowiredAnnotationProcessor' to allow for resolving potential circular references
135  [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory  - Finished creating instance of bean 'org.springframework.context.annotation.internalAutowiredAnnotationProcessor'
135  [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory  - Creating shared instance of singleton bean 'org.springframework.context.annotation.internalRequiredAnnotationProcessor'
135  [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory  - Creating instance of bean 'org.springframework.context.annotation.internalRequiredAnnotationProcessor'
136  [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory  - Eagerly caching bean 'org.springframework.context.annotation.internalRequiredAnnotationProcessor' to allow for resolving potential circular references
137  [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory  - Finished creating instance of bean 'org.springframework.context.annotation.internalRequiredAnnotationProcessor'
142  [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory  - Creating shared instance of singleton bean 'org.springframework.context.annotation.internalCommonAnnotationProcessor'
142  [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory  - Creating instance of bean 'org.springframework.context.annotation.internalCommonAnnotationProcessor'
151  [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory  - Eagerly caching bean 'org.springframework.context.annotation.internalCommonAnnotationProcessor' to allow for resolving potential circular references
151  [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory  - Finished creating instance of bean 'org.springframework.context.annotation.internalCommonAnnotationProcessor'
155  [main] DEBUG org.springframework.context.annotation.AnnotationConfigApplicationContext  - Unable to locate MessageSource with name 'messageSource': using default [org.springframework.context.support.DelegatingMessageSource@86fe26]
164  [main] DEBUG org.springframework.context.annotation.AnnotationConfigApplicationContext  - Unable to locate ApplicationEventMulticaster with name 'applicationEventMulticaster': using default [org.springframework.context.event.SimpleApplicationEventMulticaster@139eeda]
166  [main] INFO  org.springframework.beans.factory.support.DefaultListableBeanFactory  - Pre-instantiating singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@a37368: defining beans [org.springframework.context.annotation.internalConfigurationAnnotationProcessor,org.springframework.context.annotation.internalAutowiredAnnotationProcessor,org.springframework.context.annotation.internalRequiredAnnotationProcessor,org.springframework.context.annotation.internalCommonAnnotationProcessor,applicationConfig,getNotExistsPredicate]; root of factory hierarchy
166  [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory  - Returning cached instance of singleton bean 'org.springframework.context.annotation.internalConfigurationAnnotationProcessor'
166  [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory  - Returning cached instance of singleton bean 'org.springframework.context.annotation.internalAutowiredAnnotationProcessor'
166  [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory  - Returning cached instance of singleton bean 'org.springframework.context.annotation.internalRequiredAnnotationProcessor'
171  [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory  - Returning cached instance of singleton bean 'org.springframework.context.annotation.internalCommonAnnotationProcessor'
171  [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory  - Creating shared instance of singleton bean 'applicationConfig'
172  [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory  - Creating instance of bean 'applicationConfig'
174  [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory  - Eagerly caching bean 'applicationConfig' to allow for resolving potential circular references
190  [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory  - Finished creating instance of bean 'applicationConfig'
190  [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory  - Creating shared instance of singleton bean 'getNotExistsPredicate'
190  [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory  - Creating instance of bean 'getNotExistsPredicate'
196  [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory  - Returning cached instance of singleton bean 'applicationConfig'
225  [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory  - Eagerly caching bean 'getNotExistsPredicate' to allow for resolving potential circular references
232  [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory  - Finished creating instance of bean 'getNotExistsPredicate'
235  [main] DEBUG org.springframework.context.annotation.AnnotationConfigApplicationContext  - Unable to locate LifecycleProcessor with name 'lifecycleProcessor': using default [org.springframework.context.support.DefaultLifecycleProcessor@134a7d8]
235  [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory  - Returning cached instance of singleton bean 'lifecycleProcessor'
237  [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory  - Returning cached instance of singleton bean 'getNotExistsPredicate'
253  [main] DEBUG IocTest  - com.mihailenco.predicate.NotExistsPredicate@982589

Answer 3

It seems to be this feature is not supported by Spring yet. However, it can be easily implemented:

public class AnnotationConfigContextLoader implements ContextLoader {

    public ApplicationContext loadContext(String... locations) throws Exception {
        Class<?>[] configClasses = new Class<?>[locations.length];
        for (int i = 0; i < locations.length; i++) {
            configClasses[i] = Class.forName(locations[i]);
        }        
        return new AnnotationConfigApplicationContext(configClasses);
    }

    public String[] processLocations(Class<?> c, String... locations) {
        return locations;
    }
}

-

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(loader = AnnotationConfigContextLoader.class, 
    value = "com.sample.AppConfig")
public class IocTest {
    @Autowired
    TestSerivce service;

    @Test
    public void testIoc()
    {
        Assert.assertNotNull(service.getPredicate());
    }
}

-

@Configuration
public class ApplicationConfig
{
    ...

    @Bean
    public NotExistsPredicate getNotExistsPredicate()
    {
        return new NotExistsPredicate();
    }

    @Bean
    public TestService getTestService() {
        return new TestService();
    }
}