This commit adds a "spring-context-indexer" module that can be added to
any project in order to generate an index of candidate components defined
in the project.
`CandidateComponentsIndexer` is a standard annotation processor that
looks for source files with target annotations (typically `@Component`)
and references them in a `META-INF/spring.components` generated file.
Each entry in the index is the fully qualified name of a candidate
component and the comma-separated list of stereotypes that apply to that
candidate. A typical example of a stereotype is `@Component`. If a
project has a `com.example.FooService` annotated with `@Component` the
following `META-INF/spring.components` file is generated at compile time:
```
com.example.FooService=org.springframework.stereotype.Component
```
A new `@Indexed` annotation can be added on any annotation to instructs
the scanner to include a source file that contains that annotation. For
instance, `@Component` is meta-annotated with `@Indexed` now and adding
`@Indexed` to more annotation types will transparently improve the index
with additional information. This also works for interaces or parent
classes: adding `@Indexed` on a `Repository` base interface means that
the indexed can be queried for its implementation by using the fully
qualified name of the `Repository` interface.
The indexer also adds any class or interface that has a type-level
annotation from the `javax` package. This includes obviously JPA
(`@Entity` and related) but also CDI (`@Named`, `@ManagedBean`) and
servlet annotations (i.e. `@WebFilter`). These are meant to handle
cases where a component needs to identify candidates and use classpath
scanning currently.
If a `package-info.java` file exists, the package is registered using
a "package-info" stereotype.
Such files can later be reused by the `ApplicationContext` to avoid
using component scan. A global `CandidateComponentsIndex` can be easily
loaded from the current classpath using `CandidateComponentsIndexLoader`.
The core framework uses such infrastructure in two areas: to retrieve
the candidate `@Component`s and to build a default `PersistenceUnitInfo`.
Rather than scanning the classpath and using ASM to identify candidates,
the index is used if present.
As long as the include filters refer to an annotation that is directly
annotated with `@Indexed` or an assignable type that is directly
annotated with `@Indexed`, the index can be used since a dedicated entry
wil be present for that type. If any other unsupported include filter is
specified, we fallback on classpath scanning.
In case the index is incomplete or cannot be used, The
`spring.index.ignore` system property can be set to `true` or,
alternatively, in a "spring.properties" at the root of the classpath.
Issue: SPR-11890
This commit adds a test runtime dependency on log4j 2 for every project
and migrates all log4j.properties files to log4j2-test.xml files.
Issue: SPR-14431
This commit migrates all remaining tests from JUnit 3 to JUnit 4, with
the exception of Spring's legacy JUnit 3.8 based testing framework that
is still in use in the spring-orm module.
Issue: SPR-13514
HibernateEntityManagerFactoryIntegrationTests in the spring-orm module
has been disabled for quite some time due to a dependency on the
AnnotationBeanConfigurerAspect from the spring-aspects module. Since
spring-aspects depends on spring-orm, a cyclical dependency would
result if this code were re-enabled "as is".
This commit removes the dependency on AnnotationBeanConfigurerAspect in
HibernateEntityManagerFactoryIntegrationTests by deleting all test code
and configuration related to @Configurable. In addition, this commit
also deletes all SessionFactory-specific test code in
HibernateEntityManagerFactoryIntegrationTests, allowing the test class
to focus on Hibernate as a JPA provider.
Issue: SPR-11922
This commit deletes all test annotations from the spring-orm module in
order to reduce unnecessary confusion between these "copies" and the
real, current versions of such classes in the spring-test module.
Furthermore, the legacy abstract JUnit 3.8 base classes and test cases
have been refactored accordingly.
