This commit picks up where the two previous commits left off.
Specifically, this commit:
- Removes the "severity=warning" configuration to ensure that violations
actually fail the build.
- Fixes regular expressions for suppressions by matching forward
slashes using `[\\/]` instead of `\/`.
- Moves the configuration for newly introduced checks to locations in
checkstyle.xml that align with the existing organization of that file.
- Renames the IDs for RegexpSinglelineJava checks from
javaDocPackageNonNullApiAnnotation/javaDocPackageNonNullFieldsAnnotation
to packageLevelNonNullApiAnnotation/packageLevelNonNullFieldsAnnotation,
respectively, since these checks are not related to Javadoc.
- Simplifies the null-safety annotation checks to match against
imported annotation types, which enforces consistency across
package-info.java files for the annotation declarations.
- Simplifies the RegEx for JavadocPackage suppressions to only exclude
packages not under src/main/java (vs src/main) and those in the
framework-docs module.
- Consistently suppresses all checks for the `asm`, `cglib`, `objenesis`,
and `javapoet` packages in spring-core.
- Adds explicit suppressions for null-safety annotations for the `lang`
package in spring-core.
- Adds explicit suppressions for null-safety annotations for the
`org.aopalliance` package in spring-aop.
- Revises the RegEx for null-safety annotation suppressions to only
exclude package-info.java files not under src/main/java and
additionally to exclude package-info.java files in the framework-docs
module as well as those in the spring-context-indexer,
spring-instrument, and spring-jcl modules.
- Adds all missing package-info.java files.
- Adds null-safety annotations to package-info.java files where
appropriate.
Closes gh-30069
Where unfeasible, this commit adds inline comments to explain why
try-with-resources must not be used in certain scenarios. The purpose
of the comments is to avoid accidental conversion to try-with-resources
at a later date.
Closes gh-27823
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
