Spring save locale and change locale when user logs in

Question

I have a spring application that I want users to be able to change the preferred locale. Currently users can change the locale for the current session but I want to be able

Answer 1

You can implement LocaleResolver interface to bind users Locale to database. Sample implementation "ApplicationLocaleResolver.java" is below

import java.util.Locale;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Configuration;
import org.springframework.security.core.context.SecurityContext;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.web.servlet.i18n.SessionLocaleResolver;
import net.app.locale.service.UserService;

@Configuration
public class ApplicationLocaleResolver extends SessionLocaleResolver {
    @Autowired
    UserService userService;

    @Override
    public Locale resolveLocale(HttpServletRequest request) {
        SecurityContext securityContext = SecurityContextHolder.getContext();
        String userName = securityContext.getAuthentication().getName();
        String localeOption = userService.getUsersPreferedLocaleOption(userName);
        Locale userLocale = Locale.forLanguageTag(localeOption);
        return userLocale;
    }

    @Override
    public void setLocale(HttpServletRequest request, HttpServletResponse response, Locale locale) {
        super.setLocale(request, response, locale);

        SecurityContext securityContext = SecurityContextHolder.getContext();
        String userName = securityContext.getAuthentication().getName();
        userService.saveUsersPreferedLocaleOption(userName, locale);
    }
}

I assume your userService has a method that save users local to db. I prefer userService.saveUsersPreferedLocaleOption(userName, locale); You can change it.

Then you can replace localeResolver bean definition as below.

@Bean(name = "localeResolver")
public LocaleResolver localeResolver() {
    return new ApplicationLocaleResolver();
}