@Configuration
@EnableWebMvc
public class CommonConfig extends WebMvcConfigurerAdapter {
...
   @Bean
    public LocaleChangeInterceptor localeChangeInterceptor()   {
        LocaleChangeInterceptor localeChangeInterceptor = new LocaleChangeInterceptor();
        localeChangeInterceptor.setParamName("lang");
        return localeChangeInterceptor;
   }

   @Bean
    public LocaleResolver localeResolver()
    {
        return new SessionLocaleResolver();
    }

    @Override
    public void addInterceptors(InterceptorRegistry registry)
    {
        registry.addInterceptor(localeChangeInterceptor()).addPathPatterns("/**");
    }

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