See gh-19847
See gh-19792

This commit changes uses of ClassLoader.loadClass to Class.forName for
consistency with what was initiated in #19342 and better compatibility
with GraalVM.

Closes gh-19824

* pr/19764:
  Upgrade to Kafka 2.4.0 and Spring Kafka 2.4.1

Closes gh-19764

See gh-19764

Closes gh-19650

Closes gh-19873

Closes gh-19872

* pr/19855:
  Polish "Encourage use of SpringBootApplication"
  Encourage use of SpringBootApplication

Closes gh-19855

See gh-19855

See gh-19855

Closes gh-19871

Closes gh-19856

Closes gh-19870

Closes gh-19869

Closes gh-19857

Update the `Packager` to automatically add the layertools jarmode jar
when producing a layered jar.

Closes gh-19865

Update `LaunchedURLClassLoader` to ensure that the `JarModeLauncher`
is created in the correct classloader.

Prior to this commit the launcher was created by the application
classloader and did not have access to any of the required
`org.springframework` classes.

See gh-19848

Rename `spring-boot-layertools` to `spring-boot-jarmode-layertools`.

Closes gh-19853

Closes gh-19847

This class was mistakenly marked as deprecated in 2.2.0 instead of deprecated
in 2.3.0. This resulted in the class being deleted as part of the 2.3.0
cleanup.

Putting it back in place now with the correct deprecation noted.

Closes gh-19861

Update all dependencies declarations to use the form `scope(reference)`
rather than `scope reference`.

Prior to this commit we declared dependencies without parentheses unless
we were forced to add them due to an `exclude`.

Replace Gradle single quote strings with the double quote form
whenever possible. The change helps to being consistency to the
dependencies section where mostly single quotes were used, but
occasionally double quotes were required due to `${}` references.

The Spring Cloud Connectors project has been deprecated in favor of the
Java CFEnv project. The Boot auto-configuration and starter that support
Connectors were deprecated in Boot 2.2.

This commit removes the Connectors auto-configuration, starter,
and dependency management.

Closes gh-19798

Closes gh-19792
Co-authored-by: Andy Wilkinson <awilkinson@pivotal.io>

This change ensures that each test in a test suite that shares an
application context gets a unique embedded database, to prevent
inconsistent embedded database state between tests.

Closes gh-16747

Fix a bug in `ExplodedURLClassLoader` and merge the code into the
existing `LaunchedURLClassLoader` class. Also polish a few method
names relating to layer support.

See gh-19848
See gh-19767

Update `AbstractApplicationLauncher` to not attempt to shutdown
the process if startup fails.

Rename the `spring-boot-cloudnativebuildpack` module to
`spring-boot-buildpack-platform` and update the the package
name to `org.springframework.boot.buildpack.platform`.

Closes gh-19851

Change the default `BootstrapMode` for auto-configured `JpaRepositories`
to `BootstrapMode.DEFERRED` to allow the initialization of
`EntityManagerFactory` to be parallelized for increased startup efficiency.

Prior to this change, the default BootstrapMode for all auto-configured
Spring Data repositories was `BootstrapMode.DEFAULT`.

Closes gh-16230

* gh-19850:
  Treat Java 11+'s NoSuchFileException the same as FileNotFoundException

Closes gh-19850

See gh-19850

Closes gh-19652

Add a new `spring-boot-layertools` module which provides jarmode support
for working with layers. The module works with both classic fat jars,
as well as layered jars.

Closes gh-19849

Update the `Launcher` class to allow a packaged jar to be  launched in
a different mode. The launcher now checks for a `jarmode` property and
attempts to find a `JarMode` implementation using the standard
`spring.factories` mechanism.

Closes gh-19848

Update layered jar support so that the name `ext` and any name
starting `springboot` are reserved.

See gh-19767

Update the managed dependencies to include the recently added
`spring-boot-cloudnativebuildpack` module.

See gh-19828

Update `Packager` to create the layer index file when repackaging.

Closes gh-19767