Consistently use `assertThatExceptionOfType(...).isThrownBy(...)`
rather than `assertThatCode` or `assertThatThrownBy`. This aligns with
Spring Boot and Spring Cloud. It also allows the convenience
`assertThatIllegalArgument` and `assertThatIllegalState` methods to
be used.
Issue gh-8945
Remove all blank lines from test code so that test methods are
visually grouped together. This generally helps to make the test
classes easer to scan, however, the "given" / "when" / "then"
blocks used by some tests are now not as easy to discern.
Issue gh-8945
Update all ternary expressions so that the condition is always in
parentheses and "not equals" is used in the test. This helps to bring
consistency across the codebase which makes ternary expression easier
to scan.
For example: `a = (a != null) ? a : b`
Issue gh-8945
Reduce method visibility for package private classes when possible.
In the case of abstract classes that will eventually be made public,
the class has been made public and a package-private constructor has
been added.
Issue gh-8945
Use regular expression search/replace to ensure all single-arg
lambdas have parenthesis. This aligns with the style used in Spring
Boot and ensure that single-arg and multi-arg lambdas are consistent.
Issue gh-8945
Update all utility classes so that they have a private constructor. This
prevents users from accidentally creating an instance, when they should
just use the static methods directly.
Issue gh-8945
Add an additional lines after the copyright header and before the
`package` declaration. This aligns with the style used by Spring
Framework.
Issue gh-8945
Replace static imports with class referenced methods. With the exception
of a few well known static imports, checkstyle restricts the static
imports that a class can use. For example, `asList(...)` would be
replaced with `Arrays.asList(...)`.
Issue gh-8945
Migrate Mockito imports to use the BDD variant. This aligns better with
the "given" / "when" / "then" style used in most tests since the "given"
block now uses Mockito `given(...)` calls.
The commit also updates a few tests that were accidentally using
Power Mockito when regular Mockito could be used.
Issue gh-8945
Move all inner-types so that they are consistently the last item
defined. This aligns with the style used by Spring Framework and
the consistency generally makes it easier to scan the source.
Issue gh-8945
