1，在项目resources中添加配置文件

2，在模块中定一个CommonResultCode（类名自定义，可以参考SmsCommonResultCode）

自定义的key和三种语言配置文件中key要相对应

3.在项目中错题的地方直接抛出异常（ServiceException或者 GlobalException都可以，其他的也可以，需要自己实现）

不带参数的

带动态参数的

4，异常处理代码

@RestControllerAdvice
public class GlobalExceptionHandler {
      /**
     * 业务异常
     */
    @ExceptionHandler(ServiceException.class)
    public AjaxResult handleServiceException(ServiceException e, HttpServletRequest request) {
        String requestURI = request.getRequestURI();
        Integer code = e.getCode();
        Object data = e.getData();
        String message = errorMessageService.getMessage(e, null, request);
        return StringUtils.isNotNull(code) ? (data != null ? AjaxResult.error(code, message, data) : AjaxResult.error(code, message)) : (data != null ?
 AjaxResult.error(message, data) : AjaxResult.error(message));
    }
}

@Service
public class ErrorMessageService implements ApplicationContextAware {
    private static MessageSource messageSource;

    public String getMessage(IErrorCode errorCode, String lang) {
        try {
            Locale locale = LangTypeEnum.getLangByCode(lang).getLocale();
            return messageSource.getMessage(errorCode.getMsgKey(), null, locale);
        } catch (NoSuchMessageException e) {
            return errorCode.getMsgKey();
        }
    }

    public String getMessage(IErrorCode errorCode, Object[] args, String lang) {
        try {
            Locale locale = LangTypeEnum.getLangByCode(lang).getLocale();
            return messageSource.getMessage(errorCode.getMsgKey(), args,  // 支持参数替换
                    locale);
        } catch (NoSuchMessageException e) {
            return messageSource.getMessage(errorCode.getMsgKey(), args, Locale.SIMPLIFIED_CHINESE);
        }
    }

    public String getMessage(Throwable throwable, String lang, HttpServletRequest request) {
        if (StringUtils.isBlank(lang) && request != null) {
            lang = LangUtils.getLang(request).getCode();
        }
        if (lang == null) {
            lang = LangTypeEnum.ZH_CN.getCode();
        }
        if (throwable instanceof ServiceException) {
            ServiceException be = (ServiceException) throwable;
            if (be.getErrorCode() == null) {
                return be.getMessage();
            }
            return getMessage(be.getErrorCode(), be.getArgs(), lang);
        } 
            return getMessage(be.getErrorCode(), be.getArgs(), lang);
        }else if (throwable instanceof LimitException) {
            LimitException be = (LimitException) throwable;
            if (be.getErrorCode() == null) {
                return be.getMessage();
            }
            return getMessage(be.getErrorCode(), be.getArgs(), lang);
        }
        return getMessage(CommonErrorCode.SYSTEM_ERROR, new Object[]{throwable.getMessage()}, lang);
    }

    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        messageSource = applicationContext.getBean(MessageSource.class);
    }

    public static String getMessage(String propertiesKey) {
        return getMessage(propertiesKey, propertiesKey);
    }

    public static String getMessage(String propertiesKey, String defaultMessage) {
        return getMessage(propertiesKey, null, defaultMessage);
    }

    public static String getMessage(String propertiesKey, Object[] args, String defaultMessage) {
        ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
        String lang = null;
        if (attributes != null) {
            HttpServletRequest request = attributes.getRequest();
            lang = LangUtils.getLang(request).getCode();
        }
        if (lang == null) {
            lang = LangTypeEnum.ZH_CN.getCode();
        }
        return messageSource.getMessage(propertiesKey, args, defaultMessage, LangTypeEnum.getLangByCode(lang).getLocale());
    }
}

public interface IErrorCode {
    Integer getCode();

    String getModule();    // 用于区分不同模块

    String getMsgKey();    // 国际化消息的key
}

@Configuration
@AutoConfigureBefore(MessageSourceAutoConfiguration.class)
public class MessageConfig {

    @Bean
    public MessageSource messageSource() {
        ResourceBundleMessageSource messageSource = new ResourceBundleMessageSource();
        messageSource.setBasename("i18n/messages");
        messageSource.setDefaultEncoding("UTF-8");
        messageSource.setUseCodeAsDefaultMessage(true);
        return messageSource;
    }
}