Consistent URI/body decoding

[snicoll]

Spring MVC defaults to ISO-8859-1 for historical reason and it's not easy to change that value. The decoding of the URI happens at two stages: the container does it (see #542 for what we did for Tomcat since Jetty already defaults to UTF-8) and Spring MVC does it, based on the request encoding or the default if it's not set.

What people usually do is configure the org.springframework.web.filter.CharacterEncodingFilter with the same encoding as the one defined on the container. That way the body and the URI are decoded in a consistent manner.

Long story short: #542 does not fully provide a UTF-8 decoding by default. It would be nice to try to bring that property back at a generic level if we happen to be able to configure jetty: that way we can customize the uriEncoding with the use of a single property.

[making]

Japanese Spring Boot user always configure CharacterEncodingFilter like following

    @Bean
    @Order(Ordered.HIGHEST_PRECEDENCE)
    CharacterEncodingFilter characterEncodingFilter() {
        CharacterEncodingFilter filter = new CharacterEncodingFilter();
        filter.setEncoding("UTF-8");
        filter.setForceEncoding(true);
        return filter;
    }

to handle Japanese in POST request.

Autocofigured CharacterEncodingFilter would be very helpful.

[snicoll]

Not on a computer right now but a similar issue already exists FYI.

[snicoll]

Here is another related issue in Spring MVC: SPR-11925