springboot i18n国际化后台多种语言设置的方式

2022-08-20 10:06:54

之前有做过手机端后台的国际化,因为手机统一传递了language参数,所以只要设置LocaleChangeInterceptor就行了

/**
 * 配置国际化语言
 */
@Configuration
public class LocaleConfig extends WebMvcConfigurerAdapter{
	/**
     * 默认解析器 其中locale表示默认语言
     */
    @Bean
    public LocaleResolver localeResolver() {
        SessionLocaleResolver localeResolver = new SessionLocaleResolver();
        localeResolver.setDefaultLocale(Locale.CHINA);
        return localeResolver;
    }
    //springboot1.5
    @Override
    public void addInterceptors(InterceptorRegistry registry) {
    	LocaleChangeInterceptor localeInterceptor = new LocaleChangeInterceptor();
      localeInterceptor.setParamName("language");
      registry.addInterceptor(localeInterceptor);
    }
}

对于某些特殊的后台运行代码,比如定时器,我则使用getByLanguage方法

/**
 * 国际化工具类
 */
@Component
public class MessageUtils{

    private static MessageSource messageSource;
    
    static SysErrorLogDao sysErrorLogDao;

	@Resource
	public void setSysErrorLogDao(SysErrorLogDao sysErrorLogDao) {
		MessageUtils.sysErrorLogDao = sysErrorLogDao;
	}
	private static Logger logger = LoggerFactory.getLogger(MessageUtils.class);
    public MessageUtils(MessageSource messageSource) {
    	MessageUtils.messageSource = messageSource;
    }

    /**
     * 获取单个国际化翻译值
     * @param msgKey
     * @param defaultMsg
     * @return
     */
    public static String get(String msgKey, String defaultMsg) {
        try {
            return messageSource.getMessage(msgKey, null, LocaleContextHolder.getLocale());
        } catch (Exception e) {
        	logger.error(e.getMessage(), e);
        	String message = StringUtils.getExceptionStackTraceMessage(e);
			if(message != null && message.length() > 1000) {
				message = message.substring(0, 999);
			}
			SysErrorLogModel errorLog = new SysErrorLogModel();
			errorLog.setContent(msgKey);
			errorLog.setType("messageUtils");
			errorLog.setCreateDate(new Date());
			errorLog.setClassName(MessageUtils.class.getName());
			errorLog.setMessage(message);
			sysErrorLogDao.save(errorLog);
            return defaultMsg;
        }
    }
    /**
     * 获取多个参数取代的国际化翻译值
     * @param msgKey
     * @param defaultMsg
     * @param arg
     * @return
     */
    public static String get(String msgKey, String defaultMsg, Object... arg) {
        try {
        	msgKey = messageSource.getMessage(msgKey, arg, LocaleContextHolder.getLocale());
            return msgKey;
        } catch (Exception e) {
        	logger.error(e.getMessage(), e);
        	String message = StringUtils.getExceptionStackTraceMessage(e);
			if(message != null && message.length() > 1000) {
				message = message.substring(0, 999);
			}
			SysErrorLogModel errorLog = new SysErrorLogModel();
			errorLog.setContent(msgKey);
			errorLog.setType("messageUtils");
			errorLog.setCreateDate(new Date());
			errorLog.setClassName(MessageUtils.class.getName());
			errorLog.setMessage(message);
			sysErrorLogDao.save(errorLog);
            return MessageFormat.format(defaultMsg, arg);
        }
    }
    /**
     * 指定语言获得单个国际化翻译值
     * @param msgKey
     * @param defaultMsg
     * @param language
     * @return
     */
    public static String getByLanguage(String msgKey, String defaultMsg, String language) {
    	try {
    		Locale locale = new Locale(language);
        	msgKey = messageSource.getMessage(msgKey, null, locale);
            return msgKey;
        } catch (Exception e) {
        	logger.error(e.getMessage(), e);
        	String message = StringUtils.getExceptionStackTraceMessage(e);
			if(message != null && message.length() > 1000) {
				message = message.substring(0, 999);
			}
			SysErrorLogModel errorLog = new SysErrorLogModel();
			errorLog.setContent(msgKey);
			errorLog.setType("messageUtils");
			errorLog.setCreateDate(new Date());
			errorLog.setClassName(MessageUtils.class.getName());
			errorLog.setMessage(message);
			sysErrorLogDao.save(errorLog);
            return defaultMsg;
        }
    }
    /**
     * 指定语言获取多参数取代的国际化翻译值
     * @param msgKey
     * @param defaultMsg
     * @param language
     * @param arg
     * @return
     */
    public static String getByLanguage(String msgKey, String defaultMsg, String language, Object... arg) {
    	try {
    		Locale locale = new Locale(language);
        	msgKey = messageSource.getMessage(msgKey, arg, locale);
            return msgKey;
        } catch (Exception e) {
        	logger.error(e.getMessage(), e);
        	String message = StringUtils.getExceptionStackTraceMessage(e);
			if(message != null && message.length() > 1000) {
				message = message.substring(0, 999);
			}
			SysErrorLogModel errorLog = new SysErrorLogModel();
			errorLog.setContent(msgKey);
			errorLog.setType("messageUtils");
			errorLog.setCreateDate(new Date());
			errorLog.setClassName(MessageUtils.class.getName());
			errorLog.setMessage(message);
			sysErrorLogDao.save(errorLog);
            return MessageFormat.format(defaultMsg, arg);
        }
    }

}

但是后面又要做网页的国际化,因为网页没有传递统一的语言参数,如果要一一添加的话太过麻烦,于是就要用到cookie来保存传递语言

这个时候就要实现自己的解析器了

public class MyLocaleResolver implements LocaleResolver {
	@Override
    public Locale resolveLocale(HttpServletRequest httpServletRequest) {
        Locale locale = Locale.getDefault();
        {
        	//通过参数解析locale,language参数优先
        	String temp = httpServletRequest.getParameter("language");
        	if (!StringUtils.isEmpty(temp)) {
        		locale = new Locale(temp);
        		return locale;
        	}
        }
        //得到cookie,解析locale
        Cookie[] cookies = httpServletRequest.getCookies();
        if(cookies != null) {
            for (Cookie cookie : cookies) {
                if (cookie.getName().equals("userLanguage")) {
                    String temp = cookie.getValue();
                    if (!StringUtils.isEmpty(temp)) {
                        locale = new Locale(temp);
                    }
                    continue;
                }
            }
        }
        return locale;
    }

    @Override
    public void setLocale(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Locale locale) {

    }
}
@Configuration
public class LocaleConfig extends WebMvcConfigurerAdapter{
	
    @Bean
    public LocaleResolver localeResolver() {
        MyLocaleResolver localeResolver = new MyLocaleResolver();
        return localeResolver;
    }
}

这样就实现了使用cookie来设置语言


不过最后还是有所遗漏,因为我们的分布式项目中用到了很多http的内部调用,用不上cookie,也没有language参数。但是大部分的内部调用都有传递公司id,可以通过公司获得公司对应的语言。可以在拦截器里面直接加入对companyId的解析但是我考虑有没有通用的实现方法,就是在任何地方,甚至的运行到一半中途设置语言的办法。初步想法是拿到线程中的Locale进行设置

然后我看了下源码LocaleContextHolder.getLocale()

发现调用的是一个LocaleContext类的方法。

然后查询哪些地方调用了LocaleResolver.resolveLocale

发现第一个方法里面返回了一个匿名函数LocaleContext,其getLocale就是直接调用localeResolver.resolveLocale方法。于是我合理的猜想框架里不是通过拦截器设置一个locale,而是每次调用LocaleContextHolder.getLocale()都会执行localeResolver.resolveLocale(request)方法,所以我们只要设置request属性就行了

public class MyLocaleResolver implements LocaleResolver {
	@Override
    public Locale resolveLocale(HttpServletRequest httpServletRequest) {
        //得到cookie,解析locale
        Locale locale = Locale.getDefault();
        {
        	//通过参数解析locale
        	String temp = httpServletRequest.getParameter("language");
        	if (!StringUtils.isEmpty(temp)) {
        		locale = new Locale(temp);
        		return locale;
        	}
        }
        {
        	String temp = (String) httpServletRequest.getAttribute("language");
        	if (!StringUtils.isEmpty(temp)) {
        		locale = new Locale(temp);
        		return locale;
        	}
        }
        Cookie[] cookies = httpServletRequest.getCookies();
        if(cookies != null) {
            for (Cookie cookie : cookies) {
                if (cookie.getName().equals("userLanguage")) {
                    String temp = cookie.getValue();
                    if (!StringUtils.isEmpty(temp)) {
                        locale = new Locale(temp);
                    }
                    continue;
                }
            }
        }
        return locale;
    }

    @Override
    public void setLocale(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Locale locale) {

    }
}
    @RequestMapping("/test")                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
    public String test(HttpServletRequest request) {
    	String result = "";
		request.setAttribute("language", "ch");
		result += MessageUtils.get("test", "测试");
		request.setAttribute("language", "en");
		result += MessageUtils.get("test", "测试");
        return result;
    }

messages_ch.properties

test=测试

messages_en.properties

test=test

这样我们就实现了在任何地点,甚至中途变换语言了


发现LocaleContextHolder.getLocale()在实体类中也可以调用。因此可以后台保存json格式,在get方法中根据语言返回相应的值。我本来想直接改造原来的字段,但是发现缓存会直接读取get中的值,下次读取就不是json了,所以只好麻烦点增加一个字段了

	public String getFullNameByLanguage() {
		String language = LocaleContextHolder.getLocale().getLanguage();
		Map<String, String> map;
		try {
			map = JsonUtil.string2Obj(fullName);
			return map.get(language);
		} catch (IOException e) {
			return fullName;
		}
	}

当使用@Async异步方法时,LocaleContext就是空的。这时候需要强制设置语言LocaleContextHolder.setLocale(Locale locale),当然一般的方法也可以用这个来设置语言,不过这样的话就不会再调用localeResolver.resolveLocale(request)方法了

  • 作者:从心归零
  • 原文链接:https://blog.csdn.net/qq_36804701/article/details/108282775
    更新时间:2022-08-20 10:06:54