Issue: SPR-16966

Issue: SPR-17000

In order to allow Spring Framework applications running as GraalVM
native images, ReactiveAdapterRegistry should perform explicit class
checks instead of catching Throwable in order to avoid
UnsupportedFeatureError errors.

Issue: SPR-17000

Includes an efficient implementation of isEmpty(), not relying on a full entry count but rather backing out once a non-empty hash segment has been found.

Issue: SPR-16994

Issue: SPR-16992

Issue: SPR-16968

Issue: SPR-16992

Issue: SPR-16968

Issue: SPR-16981

Issue: SPR-16908

Reorganize imports to ensure consistent ordering. This commit also
expands any `.*` static imports in favor of using fully-qualified
method references.

Issue: SPR-16968

Update all lambdas that take a single argument so that parenthesis
are never used.

Issue: SPR-16968

Update code that has accidentally used spaces instead of tabs.
Also remove all trailing whitespace.

Issue: SPR-16968

Update `ConversionUtils` to remove conditional logic that isn't
necessary.

Issue: SPR-16968

Ensure that `this.` is never used when accessing loggers.

Issue: SPR-16968

Ensure that `this.` is used consistently when accessing class
fields.

Issue: SPR-16968

Update all classes so that inner classes are always last. Also
ensure that utility classes are always final and have a private
constructor and make exceptions final whenever possible.

Issue: SPR-16968

Add copyright header to `package-info.java` files and fix a few
malformed headers on existing java files.

Issue: SPR-16968

Update all files to ensure that they always end with a new line.

Issue: SPR-16968

Fix checkstyle violations for javadoc.

Issue: SPR-16968

Issue: SPR-16974

Issue: SPR-16898

Issue: SPR-12458

Issue: SPR-12458

Issue: SPR-16833

Issue: SPR-16838

Issue: SPR-12458

Allow the `Environment` to accept a generic `Profiles` interface which
can support more complex matching rules. The previous
`acceptsProfiles(String...)` method now uses `Profiles.of` which
supports basic profile expressions such as "(a | b) & !c"

Issue: SPR-12458

Issue: SPR-16889

To avoid compiler issues on Eclipse.

(cherry picked from commit a2765c00)

Issue: SPR-16926

Closes gh-1848

Issue: SPR-16892

Issue: SPR-16832

Issue: SPR-16871

Includes nullable return value for getClassLoader() with corresponding notes in applicable javadoc.

Issue: SPR-16866