Default HTTP error exceptions thrown from RestTemplate now include
response headers in addition to the response body. In particular, this
enables inspection of the Content-Type header allowing manual
deserialization of the response body without guessing as to the content
type.
- introduce HttpStatusCodeException#getResponseHeaders
- add constructor with headers param for HttpStatusCodeException,
HttpClientErrorException and HttpServerErrorException
- preserve exsisting constructor signatures
- mark HttpHeaders as Serializable
- generate new serialVersionUID where needed
Issue: SPR-7938