@Component within @Configuration class cannot @Autowire Regression [SPR-10865]

[spring-projects-issues]

Rob Winch opened SPR-10865 and commented

The following test passes with Spring 3.2.3.RELEASE and with Spring 4.0.0.M1, but fails with 4.0.0.M2 and the current snapshot (i.e. conceptually this is 4.0.0.M3-SNAPSHOT)

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(classes = {ComponentConfigTests.MyConfig.class})
public class ComponentConfigTests {
    @Autowired
    private MyConfig.MyComponent component;

    @Test
    public void componentAutowiresSuccessfully() {
    }

    @Configuration
    static class MyConfig {
        @Component
        public static class MyComponent {
        }
    }
}

These failures are causing test failures in Spring Security's tests when ran against Spring 4 that relate to issue 55 from the Spring Security Java Config project (which is now part of Spring Security).

---

Affects: 4.0 M2, 4.0 M3

Attachments:

• SPR-10865.zip (51.94 kB)

Issue Links:

• Regression with detecting nested components [SPR-10970] #15598 Regression with detecting nested components

Referenced from: commits 9bfbe36

[spring-projects-issues]

Rob Winch commented

I have attached a sample project that demonstrates the issue. You can run the following from the commandline:

./gradlew clean check

The test task will pass successfully (it uses Spring 3.2.3.RELEASE). The spring4Test will fail (it uses 4.0.0.BUILD-SNAPSHOT). Feel free to modify to try 4.0.0.M1 (works) and 4.0.0.M2 (fails) too.

[spring-projects-issues]

Juergen Hoeller commented

Alright, so now we know why ConfigurationClassUtils had a check for @Component classes there in its 'isLiteConfigurationCandidate' implementation... That method is also being used for checking nested member classes such as in your case - and that not only within @Configuration classes but within any @Component classes (see #15598). That was almost a hidden feature, with no unit tests for it on our side! In any case, restored for 4.0 RC1 now.

Juergen