The AbstractHttpMessageConverter was using the requested Content-Type
rather than the actual response Content-Type to determine the length
of the content. This can lead to a problem when a controller returns
a ResponseEntity with a Content-Type header that ignores (overrides)
the requested Content-Type. The fix ensures that actual response
Content-Type is the one used both to write to the response and to
determine the length of the content.
The UriComponentsBuilder instance passed into the method is initialized
with current request information including host, scheme, port, context
path, and the servlet mapping's literal part.
Also added shortcut methods to buildAndExpand in UriComponentsBuilder.
The initial solution kept these three in full sync at all times:
contentType field, characterEncoding field, 'Content-Type' header.
That is correct behavior, however it breaks existing tests that rely
on contentType and characterEncoding being equal to exactly what
they were set to.
For example, consider:
response.setContentType("text/plain");
response.setCharacterEncoding("UTF-8");
Ideally both contentType and the 'Content-Type' header would now be
"text/plain;charset=UTF-8". However, existing tests would expect
that contentType is equal to "text/plain".
To avoid breaking existing tests, contentType and characterEncoding
will continue to be equal to exactly what they were set to while
the 'Content-Type' header will always include both the content
type and the charset.
The only exception to this rule is when a 'Content-Type' header
is set explicitly, the contentType and characterEncoding fields will
be updated accordingly, possibly overriding the existing values.
The Content-Type header and the contentType field in HttpServletRequest/Response
are now always in sync. When a header is added the contentType field is updated
as well and vice versa.
Similarly when the Content-Type header or the contentType field includes a charset
field, the character encoding is updated and vice versa.
1. Consider single-purpose return value types like HttpEntity, Model,
View, and ModelAndView ahead of annotations like @ResponseBody and
@ModelAttribute. And reversely consider multi-purpose return value
types like Map, String, and void only after annotations like
@RB and @MA.
2. Order custom argument resolvers and return value handlers after the
built-in ones also clarifying the fact they cannot be used to override
the built-in ones in Javadoc throughout.
3. Provide hooks in RequestMappingHandlerAdapter that subclasses can use
to programmatically modify the list of argument resolvers and return
value handlers, also adding new getters so subclasses can get access
to what they need for the override.
4. Make SessionStatus available through ModelAndViewContainer and
provide an argument resolver for it.
5. Init test and javadoc improvements.
Separate client from server errors as much as possible in this order:
- raise MultipartException when resolving a multipart arg and the
request is not a multipart request (400)
- raise IllegalArgumentException when the arg type is MultipartFile
but the request is not of type MultipartHttpServletRequest (500)
- raise MissingServletRequestPartException when a MultipartResolver
is in use but the part is not found (400)
- detect presence of Servlet 3.0 before using standard multipart
parsing to find a request part or raise
IllegalArgumentException (500)
Unfortunately it is not always possible to separate client from
server errors mainly because the Servlet 3.0 API does not
distinguish between the case of 0 request parts vs multipart
processing not being configured.
Prior to this change, StandardServletEnvironment evaluated a
"jndiPropertySourceEnabled" flag to determine whether or not to add a
JndiPropertySource. Following the changes introduced in SPR-8490, there
is now no reason not to enable a JNDI property source by default. This
change eliminates the support for "jndiPropertySourceEnabled" and adds
a JndiPropertySource automatically.
Issue: SPR-8545, SPR-8490
