Add an option to not include Charset in the final http request ContentType Header

[tamimcsedu19]

I had the following problem when using RestTemplate. The FormHttpMessageConverter always adds the charset like this application/x-www-form-urlencoded; charset=UTF-8. But, the service I was consuming was malfunctioning if I give the charset like this. It was working with just application/x-www-form-urlencoded without the charset parameter. This is an external service, so I do not have control over it.

How I solved it

I subclassed MediaType, HttpHeaders and HttpEntity, so that the getMediaType method in FormHttpMessageConverter do not try to create a new MediaType with parameters.

What I am proposing

I think there should be a property in the FormHttpMessageConverter includeCharset. We do the charset validation as usual, but before writing the ContentType, we check the flag to exclude the parameter.

I am happy to give a PR if this sounds okay.

[philwebb]

The FormHttpMessageConverter is part of Spring Framework so I'll transfer the issue for that team to consider.

[poutsma]

Rather than adding another property which would be used by few people, I exposed the method that adds the charset. This way, you can override that method to do what you want.