OkHttp3 introduces a new package and API that is incompatible with
previous versions. This commit adds a new
OkHttp3ClientHttpRequestFactory and supporting classes.
Prior to this commit, the `HttpInvokerServiceExporter` would close
its `ObjectOutputStream`, which itself issues duplicate flushes on the
underlying `OutputStream`. Duplicate flushes can lead to multiple,
separate TCP packets where those should be gathered writes.
This commit wraps the underying stream with a decorator that guards
against flush calls that are duplicated with the one done in `close`.
Issue: SPR-14040
Prior to this commit, HTTP clients relying on the JDK HTTP client would
not properly reuse existing TCP connections (i.e. HTTP 1.1 persisten
connection). The SimpleClientHttpResponse would close the actual connection once the
response is handled.
As explained in the JDK documentation
(http://docs.oracle.com/javase/8/docs/technotes/guides/net/http-keepalive.html)
HTTP clients should do the following to allow resource reuse:
* consume the whole HTTP response content
* close the response inputstream once done
This commit makes sure that the response content is
totally drained and then the stream closed (and not the connection).
Issue: SPR-14040
Prior to this commit, binding a `@ModelAttribute` object as a Controller
handler paramater would instantiate the object and set all its
properties, fetching data from the request. When no data is available,
the WebDataBinder tries to bind default "empty" values:
* Boolean.FALSE for boolean types
* empty arrays for array types
* null by default
This commit adds the new default empty values:
* empty Collections for Collection types
* empty Maps for Map types
Rather than using empty implementations provided by `Collections.empty`
(which are not mutable), we're using the closest possible target type
and real implementations, provided by the `CollectionFactory`.
Issue: SPR-13502
Prior to this commit, HTTP Range requests were only supported by the
ResourceHttpRequestHandler when serving static resources.
This commit improves the ResourceHttpMessageConverter that
now supports partial writes of Resources.
For this, the `HttpEntityMethodProcessor` and
`RequestResponseBodyMethodProcessor` now wrap resources with HTTP
range information in a `HttpRangeResource`, if necessary. The
message converter handle those types and knows how to handle partial
writes.
Controller methods can now handle Range requests for
return types that extend Resource or HttpEntity:
@RequestMapping("/example/video.mp4")
public Resource handler() { }
@RequestMapping("/example/video.mp4")
public HttpEntity<Resource> handler() { }
Issue: SPR-13834
The ResourceHttpRequestHandler now relies on the conifgured
ContentNegotiationManager to determine the content type for resource
requests rather than implementing that internally.
First we check against the matched resource based on the resource file
extension. Then we expand the check against the request with any
configured content negotiation strategy.
Issue: SPR-13658
The DefaulUriTemplateHandler now provides a strictEncoding property
which if turned on encodes everything outside the reserved char set.
This is in contrast to the default policy of encoding only illegal
charaters depending on the URI component type.
Issue: SPR-11652
The new Filter is simply a new way of packaging the ability to extract
X-Forwarded-* headers already available via UriComponentsBuilder.
The Filter wraps the request and the effect is that anything using the
request will see the original schem, host, and port.
Issue: SPR-13614
Prior to this commit, `ServletWebRequest.checkNotModified` would only
support conditional GET/HEAD requests with "If-Modified-Since" and/or
"If-None-Match" request headers. In those cases, the server would return
"HTTP 304 Not Modified" responses if the resource didn't change.
This commit adds support for conditional update requests, such as
POST/PUT/DELETE requests with "If-Unmodified-Since" request headers.
If the underlying resource has been modified since the specified date,
the server will return a "409 Precondition failed" response status
to prevent concurrent updates.
Even if the modification status of the resource is reversed here
(modified vs. not modified), we're keeping here the same intent for the
return value, which signals if the response requires more processing or
if the handler method can return immediately:
```
if (request.checkNotModified(lastModified)) {
// shortcut exit - no further processing necessary
return null;
}
```
Issue: SPR-13863
Before this commit, specifying the charset to use with produces or
consumes @RequestMapping attributes resulted in default charset
loss. That was really annoying for JSON for example, where using
UTF-8 charset is mandatory in a lot of use cases.
This commit adds a defaultCharset property to
AbstractHttpMessageConverter in order to avoid losing the
default charset when specifying the charset with these
@RequestMapping attributes.
It changes slightly the default behavior (that's why we have waited
4.3), but it is much more error prone, and will match with most
user's expectations since the charset loss was accidental in most
use cases (users usually just want to limit the media type supported
by a specific handler method).
Issue: SPR-13631
This commit adds weak ETag support in ShallowEtagHeaderFilter.
This improves the behavior of the filter in tow ways:
* weak ETags in request headers such as `W/"0badc0ffee"` will be
compared with a "weak comparison" (matching both weak and strong ETags
of the same value)
* when enabled with the "writeWeakETag" init param, the filter will
write weak Etags in its HTTP responses
Issue: SPR-13778