1. Use special category prefix "spring-web.reactivestreams" for logging
of reactive streams signals in spring-web, since those are quite
verbose would fill the logs at TRACE.
2. Add and use loggers in request and websocket session implementations
separate from reactive streams bridge for regular TRACE logging.
3. Improve log messages and add where missing (e.g. for Reactor)
Issue: SPR-16898
Hiding it (at AbstractServerHttpRequest) complicates matters since
requests are often mutated and decorated, plus it's also possible to
implement the interface directly (we've one, albeit corner case).
Issue: SPR-16966
1. Eliminate WebSocketClientSupport base class whose main value was
to provide logging but those methods get in the way of inserting a
log prefix.
2. Remove checks and synchronization in lifecycle methods of Jetty
client since underlying Jetty client already has that.
This commit introduces RouterFunctions.Builder, a new way to build
router functions that does not require static imports, thus being more
discoverable and convenient.
Issue: SPR-16953
Polish a few issue identified when adding checkstyle to the
build. Although checkstyle is not enforcing rules on tests,
these are a few minor changes that are still worth making.
Issue: SPR-16968
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 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
In SPR-16892, the `EncoderHttpMessageWriter` has been improved to write
`"Content-Length"` HTTP response headers if the response body is of type
`Mono` (i.e. the actual content length is easily accessible without
buffering a possibly large response body). That change was relying on
the fact that the server side is using a `ChannelSendOperator` to delay
the writing of the body until the first signal is received.
This strategy is not effective on the client side, since no such channel
operator is used for `WebClient`. This commit improves
`EncoderHttpMessageWriter` and delays, for `Mono` HTTP message bodies
only, the writing of the body so that we can write the
`"Content-Length"` header information once we've got the body resolved.
Issue: SPR-16949
