spring-core, spring-aop and spring-context each have compile-time
dependencies on classes in the aspectjweaver jar. Prior to this commit,
only spring-core declared an optional dependency on it; now all three
do.
Issue: SPR-9683
Historically spring-orm has had an optional dependency on spring-web,
primarily in support of OpenSessionInView functionality. This optional
dependency was inadvertently made required when porting the build to
Gradle. This commit simply reintroduces the optional setting.
Issue: SPR-9632
Prior to this change, the repackaged spring-asm and spring-cglib jars
were being included wholesale in the spring-core jar, whereas the
intention was to include the unzipped classfiles.
This change ensures that spring-asm and spring-cglib jars are unzipped
on the fly when creating the spring-core jar.
Issue: SPR-9669
CGLIB 3 has been released in order to depend on ASM 4, which Spring now
depends on internally (see previous commit).
This commit eliminates spring-beans' optional dependency on cglib-nodep
v2.2 and instead repackages net.sf.cglib => org.springframework.cglib
much in the same way we have historically done with ASM.
This change is beneficial to users in several ways:
- Eliminates the need to manually add CGLIB to the application
classpath; especially important for the growing number of
@Configuration class users. Java-based configuration functionality,
along with proxy-target-class and method injection features now
work 'out of the box' in Spring 3.2.
- Eliminates the possibility of conflicts with other libraries that
may dependend on differing versions of CGLIB, e.g. Hibernate
3.3.1.ga and its dependency on CGLIB 2.1.3 would easily cause a
conflict if the application were depending on CGLIB 3 for
Spring-related purposes.
- Picks up CGLIB 3's changes to support ASM 4, meaning that CGLIB is
that much less likely to work well in a Java 7 environment due to
ASM 4's support for transforming classes with invokedynamic
bytecode instructions.
On CGLIB and ASM:
CGLIB's own dependency on ASM is also transformed along the way to
depend on Spring's repackaged org.springframework.asm, primarily to
eliminate unnecessary duplication of ASM classfiles in spring-core and
in the process save around 100K in the final spring-core JAR file size.
It is coincidental that spring-core and CGLIB currently depend on the
exact same version of ASM (4.0), but it is also unlikely to change any
time soon. If this change does occur and versions of ASM drift, then
the size optimization mentioned above will have to be abandoned. This
would have no compatibility impact, however, so this is a reasonable
solution now and for the forseeable future.
On a mysterious NoClassDefFoundError:
During the upgrade to CGLIB 3.0, Spring test cases began failing due to
NoClassDefFoundErrors being thrown from CGLIB's DebuggingClassWriter
regarding its use of asm-util's TraceClassVisitor type. previous
versions of cglib-nodep, particularly 2.2, did not cause this behavior,
even though cglib-nodep has never actually repackaged and bundled
asm-util classes. The reason for these NoClassDefFoundErrors occurring
now is still not fully understood, but appears to be due to subtle JVM
bytecode preverification rules. The hypothesis is that due to minor
changes in DebuggingClassWriter such as additional casts, access to
instance variables declared in the superclass, and indeed a change in
the superclass hierarchy, preverification may be kicking in on the
toByteArray method body, at which point the reference to the missing
TraceClassVisitor type is noticed and the NCDFE is thrown. For this
reason, a dummy implementation of TraceClassVisitor has been added to
spring-core in the org.springframework.asm.util package. This class
simply ensures that Spring's own tests never result in the NCDFE
described above, and more importantly that Spring's users never
encounter the same.
Other changes include:
- rename package-private Cglib2AopProxy => CglibAopProxy
- eliminate all 'cglibAvailable' checks, warnings and errors
- eliminate all 'CGLIB2' language in favor of 'CGLIB'
- eliminate all mention in reference and java docs of needing to add
cglib(-nodep) to one's application classpath
Issue: SPR-9669
ASM 4.0 is generally compatibile with Java 7 classfiles, particularly
including 'invokedynamic' instructions. This is important when
considering that Spring's component-scanning support is internally
ASM-based and it is increasingly likely that component classes having
invokedynamic instructions may be encountered and read by ASM.
This upgrade, then, is primarily preventive in nature.
Changes include:
- upgrade from ASM 2.2.3 to ASM 4.0
- adapt to ASM API changes as necessary throughout spring-core,
resulting in no impact to the public Spring API.
- remove dedicated spring-asm module
- use new :spring-core:asmRepackJar task to repackage
org.objectweb.asm => org.springframework.asm as per usual and write
repackaged classes directly into spring-core jar
The choice to eliminate the spring-asm module altogether and instead
inline the repackaged classes directly into spring-core is first to
eliminate an otherwise unnecessary second jar. spring-core has a
non-optional dependency on spring-asm meaning it is always on the
application classpath. This change simplifies that situation by
consoliding two jars into one. The second reason for this choice is in
anticipation of upgrading CGLIB to version 3 and inlining it into
spring-core as well. See subsequent commit for details.
Issue: SPR-9669
JarJar 1.3 now uses ASM 4 in order to be compatible with Java 7
'invokedynamic' instructions. This is not an immediate concern for
the classes that we use JarJar to repackage and transform, but is a
timely upgrade in anticipation of the subsequent commits in which we
upgrade Spring's own dependency on ASM from 2.2.3 to 4.0 and Spring's
dependency on CGLIB from 2.2 to 3.0 (which in turn depends on ASM 4.0).
See https://code.google.com/p/jarjar/wiki/ChangeLog
Issue: SPR-9669
As a result of the refactoring, the AsyncContext dispatch mechanism is
used much more centrally. Effectively every asynchronously processed
request involves one initial (container) thread, a second thread to
produce the handler return value asynchronously, and a third thread
as a result of a dispatch back to the container to resume processing
of the asynchronous resuilt.
Other updates include the addition of a MockAsyncContext and support
of related request method in the test packages of spring-web and
spring-webmvc. Also an upgrade of a Jetty test dependency required
to make tests pass.
Issue: SPR-9433
Previously only **/*.java sources files were included in the sources
jars. This is not ideal for the spring-aspects jar nor does it match
prior versions of the sources jars.
Now **/*.aj files are included in addition to the **/*.java files.
Issue: SPR-9576
The HTTP PATCH method is now supported whereever HTTP methods are used.
Annotated controllers can be mapped to RequestMethod.PATCH.
On the client side the RestTemplate execute(..) and exchange(..)
methods can be used with HttpMethod.PATCH. In terms of HTTP client
libraries, Apache HttpComponents HttpClient version 4.2 or later is
required (see HTTPCLIENT-1191). The JDK HttpURLConnection does not
support the HTTP PATCH method.
Issue: SPR-7985
Introduced ContentNeogtiationStrategy for resolving the requested
media types from an incoming request. The available implementations
are based on path extension, request parameter, 'Accept' header,
and a fixed default content type. The logic for these implementations
is based on equivalent options, previously available only in the
ContentNegotiatingViewResolver.
Also in this commit is ContentNegotiationManager, the central class to
use when configuring content negotiation options. It accepts one or
more ContentNeogtiationStrategy instances and delegates to them.
The ContentNeogiationManager can now be used to configure the
following classes:
- RequestMappingHandlerMappingm
- RequestMappingHandlerAdapter
- ExceptionHandlerExceptionResolver
- ContentNegotiatingViewResolver
Issue: SPR-8410, SPR-8417, SPR-8418,SPR-8416, SPR-8419,SPR-7722
Some Spring Framework users and teams cannot use transitive dependency
management tools like Maven, Gradle and Ivy. For them, a `distZip` task
has been added to allow for creating a Spring Framework distribution
from source that includes all optional and required runtime
dependencies for all modules of the framework.
This 'dist-with-deps' zip is not published to the SpringSource
repository nor to the SpringSource community download page. It is
strictly an optional task introduced as a convenience to the users
mentioned above.
Detailed instructions for building this zip locally have been added to
the wiki and the README has been updated with a link to that new doc.
Issue: SPR-6575
A recent commit made aopalliance optional for spring-aop, while
continuing to require it for spring-tx. On review, this is probably
overly aggressive, and for convenience aopalliance should remain
required for spring-aop. There are use cases for which aopalliance is
indeed optional, but core functionality such as <aop:scoped-proxy>
should never result in a ClassNotFoundException.
This commit returns the aopalliance dependency for spring-aop to
required status, and also explicitly notes the same dependency in other
modules that compile directly against aopalliance types.
Issue: SPR-9501
The junit:junit Maven artifact includes a bundled version of hamcrest
core. For projects that depend on later versions of hamcrest this causes
significant issues in terms of dependency management.
The spring-test module now depends on junit:junit-dep, thus allowing
developers to better manage their test dependencies on a more fine
grained level.
Also tidied up dependency issues regarding hamcrest-core and
hamcrest-all across the build.
Issue: SPR-6966
- Explicitly specify compile-time dependencies on other spring-*
modules, primarily for accuracy in pom generation and ensuring
minimal dependencies for users of spring-aspects.
- Remove use of p: namespace from annotation-cache-aspectj.xml to
avoid parser-related test failures under Eclipse (likely due to
classpath differences between Gradle and Eclipse).
The spring-intstrument jar should have a 'Premain-Class:' manifest
entry in order to enable use as a Java agent. This entry was present in
versions 3.1.1 and earlier, but due to build infrastructure changes
starting in 3.2.x this entry was missed. It is now back in place as
expected.
Issue: SPR-9458
Gradle-generated poms thoroughly tested against 3.1.1 versions, with an
eye toward making as many spring-* dependencies optional as possible.
All spring-* modules now declare a Gradle dependency on any other
spring-* module where there is a direct compile-time usage of the
sources in that module. Previously, dependency declarations were
minimal, letting transitive resolution do most of the work. However,
this creates less than ideal poms and is generally not very
informative.
So for example, spring-jdbc uses spring-core, spring-beans and
spring-tx classes directly. Therefore it has the following declarations:
compile project(":spring-core")
compile project(":spring-beans")
compile project(":spring-tx")
spring-core depends on spring-asm, but spring-jdbc does not use
spring-asm classes directly. Therefore spring-jdbc does not declare a
dependency on spring-asm. Transitive resolution is fine in such a case.
As for optional dependencies, it is a matter of degrees what
constitutes optional. A rule of thumb is whether there are legitimate
and likely use cases in which the module can be used without needing
the dependency. spring-jdbc has only one compile-time dependency on
spring-context classes, and that's in JndiDataSourceLookup. It is
certainly reasonable to imagine using spring-jdbc without JNDI,
therefore the spring-context dependency is declared optional as
follows:
compile(project(":spring-context"), optional) // for JndiDataSourceLookup
In Spring 3.1 the spring-test Maven artifact did not have a required
dependency on spring-core, but there is practically no part of
spring-test that can be used without spring-core. Most test utilities
that are intended to be stand-alone utilities in fact use utility
classes from spring-core (e.g., ReflectionTestUtils). Even some of the
web mocks/stubs use spring-core (e.g., DelegatingServletInputStream).
In addition, the current Gradle build configuration for the spring-test
module is very simplistic -- in that it does not explicitly list any
optional dependencies such as the Servlet and Portlet APIs -- and it
defines a 'compile' dependency on spring-webmvc-portlet.
The resulting Maven dependencies in the generated POM are therefore not
what a typical consumer of the spring-test artifact would reasonably
expect.
To address these issues, the Gradle build configuration for the
spring-test module now explicitly defines the following 'compile'
dependencies:
- spring-core
- spring-webmvc, optional
- spring-webmvc-portlet, optional
- junit, optional
- testng, optional
- servlet-api, optional
- jsp-api, optional
- portlet-api, optional
- activation, provided
The only required dependency is now spring-core; all other dependencies
are 'optional'.
Issue: SPR-8861
Before this change JibxMarshallerTests would fail on Windows with an
error message explaining that JiBX compiler generated classes are not
found on the classpath for binding with name 'binding'. Tests would
execute well on Linux and OS X.
Actual root cause of this bug is found to be in JiBX 1.1.5 release that
is used to build Spring. The binding name can be explicitly specified in
JiBX binding file. If omitted, when generating classes the JiBX compiler
as fall-back mechanism tries to derive the binding name from the binding
file name. That logic had a bug which gets manifested when configured
binding file path has mixed Windows and *nix style file separators, as
in case of JibxMarshallerTests being executed on a Windows platform.
This commit resolves this issue by upgrading Spring's build from JiBX
1.1.5 to 1.2.3, as the bug mentioned was fixed in JiBX 1.2. See JIBX-441
for more details.
Issue: SPR-8360
The Spring TestContext Framework (TCF) currently builds against TestNG
5.10. Thus in order to ensure that the TCF builds against the latest
release of TestNG without issues and in order to investigate the
possibility of integrating with newer TestNG features, we are upgrading to
version 6.5.2.
Note, however, that the Gradle build currently does not execute any TestNG
tests; this will be addressed in SPR-9398.
Issue: SPR-8221
Spring currently builds against JUnit 4.9; however, in order to ensure
that the Spring TestContext Framework builds and runs against JUnit 4.10
without issues and in order to investigate the possibility of integrating
with newer JUnit features, we are upgrading to JUnit 4.10.
Issue: SPR-9277
Jackson 2 uses completely new package names and new maven artifact ids.
This change adds Jackson 2 as an optional dependency and also provides
MappingJackson2HttpMessageConverter and MappingJackson2JsonView for use
with the new version.
The MVC namespace and the MVC Java config detect and use
MappingJackson2HttpMessageConverter if Jackson 2 is present.
Otherwise if Jackson 1.x is present,
then MappingJacksonHttpMessageConverter is used.
Issue: SPR-9302
Previously depending on 1.5.10 in certain locations, which caused
NoClassDefFoundErrors in EhCacheCacheTests and other tests due to
mismatches between slf4j -api and -log4j12 versions.
With the exception of one transitive dependency via Hibernate 3.3.1.GA,
all slf4j dependencies are now pegged at 1.6.1 (and all tests pass).
Before this change, IDE settings generated via import-into-eclipse.sh
created a classpath dependency on slf4j-api version 1.6.1 and
slf4j-log4j12 version 1.5.10. As a result running tests inside the IDE
resulted in a NoSuchMethodException.
build.gradle sets the variable slf4jLog4jVersion to '1.5.10'. However,
the hibernate-validator dependency in spring-context pulls in
slf4j-api version 1.6.1. The change ensures the version specified in
the build script variable is used consistently. Whether it should be
1.5.10 or 1.6.1 is a separate concern.
- Spring remains compatible against AJ version 1.6.8, but is now
compiling and testing against 1.6.12
- Encountered what appears to be an AJ bug introduced in 1.6.10: an
assertion in org.aspectj.weaver.UnresolvedType causes a false
negative failure when encountering org.springframework.io.Resource
arrays, e.g. "[org.springframework.io.Resource@xxx". This problem
has been reported to the AJ team and in the meantime, the recommended
workaround is to disable assertions either completely, or at least
selectively with
-disableassertions:org.aspectj.weaver.UnresolvedType
Issue: SPR-7989, SPR-9272
- Fix deprecation warnings about dynamic properties; favor use of
"extra properties extensions" per [1]
- Certain such deprecations are still issued due to violations within
the docbook-reference plugin. These will be fixed in an upcoming
revision of the plugin, at which point spring-framework will upgrade
to depend on it and these warnings will be eliminated
[1] http://gradle.org/docs/current/dsl/org.gradle.api.plugins.ExtraPropertiesExtension.html
Issue: SPR-9327
- Rename customized .wrapper to default gradle/wrapper directory for
out of the box compatibility with STS Gradle tooling
- Add .settings/gradle directory to capture defaults when using STS
Gradle tooling to import projects
The build script should work against http anyway; use of https here was
an oversight. Changing it now is in response to the following build
failure experienced by a user on his initial attempt to build from
source (with --info output):
09:02:09.437 [ERROR] [org.gradle.BuildExceptionReporter] Caused
by: javax.net.ssl.SSLPeerUnverifiedException: peer not authenticated
...
Cause: Could not GET
https://repo.springsource.org/plugins-snapshot/org/springframework/
build/gradle/docbook-reference-plugin/0.1.2-SNAPSHOT/maven-metadata.xml
The actual cause is unknown at this time, but worth noting that upon
switching the url to http, the following log message was issued:
Forcing close on abandoned resource: Http GET Resource:
http://repo.springsource.org/plugins-snapshot/org/springframework/
build/gradle/docbook-reference-plugin/0.1.2-SNAPSHOT/maven-metadata.xml
Previously, the build script was configured to add ajbuilder to the set
of Eclipse/STS build commands, meaning that both javabuilder and
ajbuilder would be present for spring-aspects. This causes unpredictable
behavior, as these two builders compete with each other. As ajbuilder is
a functional superset of javabuilder, this commit ensures that only the
former is present for spring-aspects' .project file.
Also removed warning language in import-into-eclipse.sh about
spring-aspects failing after adding Git support, as this intermittent
problem was almost certainly an artifact of the situation described
above.
- Fix compileTestJava issue in which test classes were not being
compiled or run
- Use built-in eclipse.project DSL instead of withXml closure
to add AspectJ nature and builder
- Rename {aspectJ=>aspects}.gradle and format source
e.g.:
Implementation-Title: spring-core
Implementation-Version: 3.2.0.BUILD-SNAPSHOT
Setting these values is good as a general practice, but required in
order to support the functionality in spring-core's SpringVersion class.
Understanding Gradle pom generation
-------------------------------------------
All spring-* subprojects have had Gradle's 'maven' plugin applied to
them. This means that one can run `gradle install`, and POMs will be
generated according to the metadata in the build.gradle file.
The 'customizePom' routine added by this commit hooks into this
generation process in order to add elements to the pom required for
entry into Maven Central via oss.sonatype.org[1].
This pom generation happens on-the-fly during `gradle install` and
the generated poms exist only in your local .m2 cache. Therefore,
you will not see the poms on the source tree after this command.
Handling optional and provided dependencies
-------------------------------------------
Note particularly the handling of 'optional' and 'provided'
dependencies. Gradle does not have a first class notion for these
concepts, nor are they significant to the actual Gradle build process,
but they are important when publishing POMs for consumption via Maven
Central and other Maven-compatible repositories.
<optional>true</optional> indicates that a dependency need not be
downloaded when resolving artifacts. e.g. spring-context has an
compile-time dependency on cglib, but when a Spring user resolves
spring-context from Maven Central, cglib should *not* automatically
be downloaded at the same time. This is because the core functionality
within spring-context can operate just fine without cglib on the
classpath; it is only if the user chooses explicitly to use certain
functionality, e.g. @Configuration classes, which do require cglib,
that the user must declare an explicit dependency in their own build
script on cglib.
Marking these kinds of dependencies as 'optional' provides a kind of
built in 'documentation' about which version of cglib the user should
declare if in fact he wishes to.
Spring has a great many compile-time dependencies, but in fact very
few mandatory runtime dependencies. Therefore, *most* of Spring's
dependencies are optional.
<scope>provided</scope> is similar to 'optional', in that dependencies
so marked should not be automatically downloaded during dependency
resolution, but indicates rather that they are expected to have been
provided by the user application runtime environment. For example, the
Servlet API is in fact a required runtime dependency for spring-webmvc,
but it is expected that it will be available via the user's servlet
container classpath. Again, it serves here as a kind of 'documentation'
that spring-webmvc does in fact expect the servlet api to be available,
and furthermore which (minimum) version.
This commit adds two closures named 'optional' and 'provided' as well as
two arrays (optionalDeps, providedDeps) for tracking which dependencies
are optional or provided. An optional dependency is declared as follows:
compile("group:artifact:version", optional)
Here, the optional closure accepts the dependency argument implicitly,
and appends it to the 'optionalDeps' array. Then, during pom generation
(again, the customizePom routine), these arrays are interrogated, and
pom <dependency> elements are updated with <optional>true</optional> or
<scope>provided</scope> as appropriate. Thanks to the Spock framework
for inspiration on this approach[2].
[1] http://bit.ly/wauOqP (Sonatype's central sync requirements)
[2] https://github.com/spockframework/spock/blob/groovy-1.7/gradle/publishMaven.gradle#L63
Only a select few EBR dependencies now remain, because these
dependencies cannot be found elsewhere e.g. atinject-tck, or in the case
of Hibernate 3.3.1.GA, to avoid Gradle classpath confusion with
Hibernate 4.0.x (because they have different artifactIds).
Future efforts will be made to fully eliminate these dependencies in
order to ensure we're decoupled completely from EBR.
Important note: these remaining EBR dependencies do not constitute a
problem when publishing artifacts into Maven Central via
oss.sonatype.org, because they are each 'optional' dependencies. It
appears that OSO's restriction around transitive dependencies being
'self-contained' within Maven Central only applies to mandatory
dependencies (which is a good thing for cases just such as this).
Add explicit /ebr-maven-external entry to repositories, as EBR
dependencies are not available via /libs-release.
- Apply custom-built Gradle 'bundlor' plugin
This plugin wraps the existing bundlor ant task. Sources available
at https://github.com/SpringSource/gradle-plugins.
- Use existing template.mf files
The bundlor plugin allows for 'inlining' bundlor templates directly
within build.gradle using the 'importTemplate' property, but opting
for now to keep the template.mf files separate.
- Exclude spring-aspects from bundlor processing
It appears that the bundlor plugin somehow interferes with iajc
compilation of aspects, resulting in compiler errors. Bundlor
has been disabled for this project for the time being.
- Fail the build on any bundlor warning
The gradle bundlor plugin defaults to failing the build if there are
any warnings when processing template.mf files. This helps to ensure
that template.mf files don't drift too far from actual dependency
declarations. This behavior can be modified by setting
bundlor {
failOnWarnings = false
}
in the build script.
- Generate castor test classes with genCastor task
- Generate xmlbeans test classes with genXmlbeans task
- Generate JAXB2 test classes with genJaxb task
- Generate JiBX bindings by extending existing compileTestJava task
Test classes are written into their own dedicated output folders and
tied into the spring-oxm classpath using the files(...).builtBy(...)
directive.
Incremental build works as expected across all of these customizations.
`gradle eclipse` and `gradle idea` generate correct .project / .iml
metadata respectively, i.e., these special cases do not cause a problem
in the IDE (as they used to prior to the move to Gradle).
Each spring-* subproject now has sourcesJar and javadocJar tasks
- Ignore subproject overview.html files for now (not all have one)
- Ensure @author attribution occurs
- Javadoc 'header' is project description
spring-asm is a special case
- source jar is created, but empty (to comply with entry rules for
Maven Central)
- add package-info.java explaining the nature of spring-asm
this is nice, because it shows up in the public API docs now.
- add SpringAsmInfo in the org.springframework.asm package as a
placeholder allowing the generation of javadocs (see link to bug)
- add explicit 'repackageAsm' Gradle task allowing for easy testing
and merging of jar containing bundlor manifest as well as jar
containing repackaged ASM classes.
- Add 'api' gradle task to generate project-wide API Javadoc
results in <root>/build/api
- Add docsZip task including api and reference documentation
suitable for publication to
http://static.springframework.org/docs/spring-framework
- Add schemaZip task including all spring-* XSD files
suitable for publication to http://static.springframework.org/schema
- Add distZip task to include all libs, docs and schema
- filter src/dist/*.txt for ${copyright} and ${version}
- copy legal (notice, license) dynamically into individual jar files
- copy legal and readme files into root of distribution zip
- Refactor location of 'wrapper' task
Each of the zip tasks (docsZip, schemaZip, distZip) have been added to
the 'archives' configuration, meaning that (a) they will be built
automatically with `gradle build` and (b) will be published
automatically to artifactory when using the Artifactory Gradle plugin
and/or Artifactory Bamboo integration.
Prior to this change, license.txt and notice.txt files were duplicated
across every subproject in their respective src/main/resources/META-INF
directories.
This commit centralizes these files under the root project at src/dist,
along with the changelog and readme files. The definition of the 'jar'
task has been been extended to include the license and notice files in
module jars as they are created.
The directory is named src/dist because these files are all related to
distribution - the readme is different than the one you see at the root
of the source tree - the intended audience is for users who download
the spring-framework distribution zip. A task to create that
distribution zip will be added in subsequent commits.
The docbook-gradle-plugin has been custom-developed specifically to
handle Spring projects. It is highly opinionated, and not terribly
configurable in its current form. Sources and documentation are
available via the 'gradle-plugins' github repository at
https://github.com/cbeams/gradle-plugins
Note that this repository may soon move locations to the SpringSource
GitHub organization, in which case the url will be
https://github.com/SpringSource/gradle-plugins
In any case, the build plans for these plugins can be found at
https://build.springsource.org/browse/GRADLEPLUGINS
This commit eliminates the 'integration-tests' subproject in favor of
managing these sources under the root project's own 'src' directory.
This helps to avoid special-case handling for integration-tests in the
Gradle build, e.g. avoiding publication of jars to Artifactory /
Maven Central.
It is also semantically more correct. This is not a Spring Framework
subproject so much as it is a collection of integration tests that
span functionality across many subprojects. In this way, it makes
sense to place them directly under the root project.
Issue: SPR-8116
Chris Beams
Rossen Stoyanchev
Sam Brannen
Rob Winch
Juergen Hoeller
Stevo Slavic
Kris De Volder