LocaleConfiguration.java

package com.mycompany.myapp.config;

import com.mycompany.myapp.config.locale.AngularCookieLocaleResolver;
import org.springframework.boot.bind.RelaxedPropertyResolver;
import org.springframework.context.EnvironmentAware;
import org.springframework.context.MessageSource;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.support.ReloadableResourceBundleMessageSource;
import org.springframework.core.env.Environment;
import org.springframework.web.servlet.LocaleResolver;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
import org.springframework.web.servlet.i18n.LocaleChangeInterceptor;

@Configuration
public class LocaleConfiguration extends WebMvcConfigurerAdapter implements EnvironmentAware {

    private RelaxedPropertyResolver propertyResolver;

    @Override
    public void setEnvironment(Environment environment) {
        this.propertyResolver = new RelaxedPropertyResolver(environment, "spring.messageSource.");
    }

    @Bean(name = "localeResolver")
    public LocaleResolver localeResolver() {
        final AngularCookieLocaleResolver cookieLocaleResolver = new AngularCookieLocaleResolver();
        cookieLocaleResolver.setCookieName("NG_TRANSLATE_LANG_KEY");
        return cookieLocaleResolver;
    }

    @Bean
    public MessageSource messageSource() {
        final ReloadableResourceBundleMessageSource messageSource = new ReloadableResourceBundleMessageSource();
        messageSource.setBasename("classpath:/i18n/messages");
        messageSource.setDefaultEncoding("UTF-8");
        messageSource.setCacheSeconds(propertyResolver.getProperty("cacheSeconds", Integer.class, 1));
        return messageSource;
    }

    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        final LocaleChangeInterceptor localeChangeInterceptor = new LocaleChangeInterceptor();
        localeChangeInterceptor.setParamName("language");

        registry.addInterceptor(localeChangeInterceptor);
    }
}