Refactor `PropertyMapper` so that it no longer calls adapter or
predicate methods by default when the source value is `null`. This
effectively makes all default calls the same as using
`alwaysWhenNotNull` in the previous generation of the code.
For the limited times when you do need to deal with `null` values, the
new `always()` method can be used.
For example,
map.from(source::method).to(destination::method);
Will not call `destination.method(...)` if `source.method()` returns
`null`.
Where as:
map.from(source::method).always().to(destination::method);
Will call `destination.method(null)` if `source.method()` returns
`null`.
This update provides clearer semantics for the API and allows for better
JSpecify nullability annotations. It has also simplified much of our
existing property mapper code.
Closes gh-47024
Co-authored-by: Moritz Halbritter <moritz.halbritter@broadcom.com>
Spring Framework 7.0 requires a Servlet 6.1 baseline for Servlet containers.
Partial Servlet 6.1 support is available on the `main` Undertow branch,
but there isn't any milestone version available for the undertow 2.4
generation. At this stage of our 4.0 schedule, we think it's safer to drop
Undertow support now.
Closes: gh-46917
Phillip Webb
Andy Wilkinson
Moritz Halbritter
Brian Clozel