Spring LocalResolver 基于查询参数“lang=en”？

Question

我可以告诉spring-boot自动解析查询参数所请求locale的，例如&lang=en吗？我想让查询参数优先于Accept-Language参数。我发现了以下两个属性，但与查询参数无关。spring.mvc.locale= # Locale to use. By default, this locale is overridden by the "Accept-Language" header.spring.mvc.locale-resolver=accept-header # Define how the locale should be resolved.我尝试如下，这给出了一个例外：@Configurationpublic class AppConfig extends WebMvcConfigurerAdapter {   @Bean   public LocaleChangeInterceptor localeChangeInterceptor() {       LocaleChangeInterceptor lci = new LocaleChangeInterceptor();       lci.setParamName("lang");       return lci;   }   @Override   public void addInterceptors(InterceptorRegistry registry) {       registry.addInterceptor(localeChangeInterceptor());   }}结果是：java.lang.UnsupportedOperationException: Cannot change HTTP accept header - use a different locale resolution strategy

Answer 1

解决办法大概如下。我仍然发现设置非常违反直觉。特别是我会期望：

• 将LocaleChangeInterceptor自身注册，但不并有来电addInterceptors()显

• 该spring.mvc.locale参数仍然设置到自定义 LocaleResolver 中，但不会并且必须从WebMvcProperties

如果需要所有这些，文档可能需要对此进行更多解释。

@Configuration

public class AppConfig extends WebMvcConfigurerAdapter {

   @Bean

   public LocaleChangeInterceptor localeChangeInterceptor() {

       LocaleChangeInterceptor lci = new LocaleChangeInterceptor();

       lci.setParamName("lang");

       return lci;

   }

   @Override

   public void addInterceptors(InterceptorRegistry registry) {

       registry.addInterceptor(localeChangeInterceptor());

   }

   @Bean

   public AcceptHeaderLocaleResolver localeResolver(WebMvcProperties mvcProperties) {

        AcceptHeaderLocaleResolver localeResolver = new AcceptHeaderLocaleResolver() {

            @Override

            public void setLocale(HttpServletRequest request, HttpServletResponse response, Locale locale) {

                LocaleContextHolder.setLocale(locale);

            }

        };

        localeResolver.setDefaultLocale(mvcProperties.getLocale());

        return localeResolver;

    }

}

讨论后更新改进版本：

@Configuration

public class AppConfig implements WebMvcConfigurer {

   @Bean

   public AcceptHeaderLocaleResolver localeResolver(WebMvcProperties mvcProperties) {

        AcceptHeaderLocaleResolver localeResolver = new AcceptHeaderLocaleResolver() {

        @Override

        public Locale resolveLocale(HttpServletRequest request) {

            String locale = request.getParameter("lang");

            return locale != null

                    ? org.springframework.util.StringUtils.parseLocaleString(locale)

                    : super.resolveLocale(request);

        }

        };

        localeResolver.setDefaultLocale(mvcProperties.getLocale());

        return localeResolver;

    }

}