Prior to this commit, `@ExceptionHandler` annotated controller methods
could be mapped using the exception type declaration as an annotation
attribute, or as a method parameter.
While such methods support a wide variety of method arguments and return
types, it was not possible to declare the same exception type on
different methods (in the same controller/controller advice).
This commit adds a new `produces` attribute on `@ExceptionHandler`; with
that, applications can vary the HTTP response depending on the exception
type and the requested content-type by the client:
```
@ExceptionHandler(produces = "application/json")
public ResponseEntity<ErrorMessage> handleJson(IllegalArgumentException exc) {
return ResponseEntity.badRequest().body(new ErrorMessage(exc.getMessage(), 42));
}
@ExceptionHandler(produces = "text/html")
public String handle(IllegalArgumentException exc, Model model) {
model.addAttribute("error", new ErrorMessage(exc.getMessage(), 42));
return "errorView";
}
```
This commit implements support in both Spring MVC and Spring WebFlux.
Closes gh-31936
Prior to this commit, `DataBufferLimitException` would be thrown by
codecs when the request body was too large for the configured buffer
limit. This exception would not be handled by the web infrastructure and
would result in an HTTP 500 server error.
This commit introduces a new `PayloadTooLargeException` type that will
result in an HTTP 413 "Payload too large" response status.
Closes gh-32558
This commit ensures that a copy is made of old attributes before
replacing it with new attributes. Because new attributes can be
composed of old, clearing the old would also remove entries from the
new.
See gh-32245
This commit introduces
BodyInserters.fromValue(T, ParameterizedTypeReference<T>) variant as
well as related WebClient.RequestBodySpec API,
ServerResponse.BodyBuilder API and Kotlin extensions.
Closes gh-32713
This commit ensures that `InvocableHandlerMethod` executes the method
on the desired thread if a non-blocking thread is specified, even in the
case where arguments resolution happens on a different thread. This is
notably the case if the method body is resolved as an input argument to
the controller method (`@RequestBody`).
Closes gh-32502
This commit introduces support for org.webjars:webjars-locator-lite
via a new LiteWebJarsResourceResolver in Spring MVC and WebFlux, and
deprecates WebJarsResourceResolver which is performing a classpath
scanning that slows down application startup.
Closes gh-27619
Javadoc doesn't seem to like having `e.g.` as it thinks the sentence
ends there, which is usually incorrect and results in broken descriptions.
This commit rewords the doc strings slightly to avoid problematic parts.
Closes gh-32532
Prior to this commit when a required parameter defined as a property or
expression placeholder was missing, the exception thrown would refer to
the placeholder instead of the resolved name.
This change covers messaging handlers and web controllers, both blocking
and reactive. It also fixes the error message when handling null values
for non-required parameters, as well as in cases that need conversion.
See gh-32323
Closes gh-32462
Historically, we have rarely intentionally thrown a
NullPointerException in the Spring Framework. Instead, we prefer to
throw either an IllegalArgumentException or IllegalStateException
instead of a NullPointerException.
However, changes to the code in recent times have introduced the use of
Objects.requireNonNull(Object) which throws a NullPointerException
without an explicit error message.
The latter ends up providing less context than a NullPointerException
thrown by the JVM (since Java 14) due to actually de-referencing a
null-pointer. See https://openjdk.org/jeps/358.
In light of that, this commit revises our current use of
Objects.requireNonNull(Object) by removing it or replacing it with
Assert.notNull().
However, we still use Objects.requireNonNull(T, String) in a few places
where we are required to throw a NullPointerException in order to
comply with a third-party contract such as Reactive Streams.
Closes gh-32430
Prior to this commit, gh-21783 introduced `ReadOnlyHttpHeaders` to avoid
parsing media types multiple times during the lifetime of an HTTP
exchange: such values are cached and the headers map is made read-only.
This also added a new `HttpHeaders.writableHttpHeaders` method to unwrap
the read-only variant when needed.
It turns out this method sends the wrong signal to the community
because:
* the underlying map might be unmodifiable even if this is not an
instance of ReadOnlyHttpHeaders
* developers were assuming that modifying the collection that backs the
read-only instance would work around the cached values for
Content-Type and Accept headers
This commit adds more documentation to highlight the desired behavior
for cached values by the read-only variant, and deprecates the
`writableHttpHeaders` method as `ReadOnlyHttpHeaders` is package private
and we should not surface that concept anyway.
Instead, this commit unwraps the read-only variant if needed when a new
HttpHeaders instance is created.
Closes gh-32116
This commit ensures pathExtension predicate is skipped when the value
is null, in order to provide a more predictable behavior, and allow
a better compatibility with collections not supporting null elements
like the ones created by List#of.
Closes gh-32404