在SpringBoot项目中如何实现国际化（i18n）？

spring.messages.basename=messages
spring.messages.cache-duration=3600 # 缓存时长，单位秒
spring.messages.encoding=UTF-8      # 设置编码格式为UTF-8

greeting=你好
farewell=再见

greeting=Hello
farewell=Goodbye

greeting=Bonjour
farewell=Au revoir

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
import org.springframework.web.servlet.i18n.AcceptHeaderLocaleResolver;
import org.springframework.web.servlet.i18n.LocaleResolver;

import java.util.Locale;

@Configuration
public class LocaleConfig implements WebMvcConfigurer {

    @Bean
    public LocaleResolver localeResolver() {
        AcceptHeaderLocaleResolver resolver = new AcceptHeaderLocaleResolver();
        resolver.setDefaultLocale(Locale.CHINA);  // 默认设置中文
        return resolver;
    }
}

import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class GreetingController {

    @Value("${greeting}")
    private String greeting;

    @GetMapping("/greet")
    public String greet() {
        return greeting;
    }
}

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.MessageSource;
import org.springframework.context.i18n.LocaleContextHolder;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class GreetingController {

    @Autowired
    private MessageSource messageSource;

    @GetMapping("/greet")
    public String greet() {
        Locale locale = LocaleContextHolder.getLocale();
        return messageSource.getMessage("greeting", null, locale);
    }
}

import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.servlet.i18n.CookieLocaleResolver;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.util.Locale;

@RestController
public class LanguageController {

    @GetMapping("/change-language")
    public String changeLanguage(@RequestParam String lang, HttpServletRequest request, HttpServletResponse response) {
        Locale locale = new Locale(lang);
        request.getSession().setAttribute(CookieLocaleResolver.LOCALE_SESSION_ATTRIBUTE_NAME, locale);
        return "Language changed to " + lang;
    }
}