Spring Boot 入门 - 基础篇（7）- 国际化

Spring Boot默认支持国际化配置，只需要添加配置文件即可。

（1）配置文件
放在/src/main/resources/文件夹下即可

• messages.properties 默认
• messages_en.properties（英文）
• messages_zh.properties（中文）
• messages_ja.properties（日文）

（2）默认配置

引用

spring.messages.always-use-message-format=false # Set whether to always apply the MessageFormat rules, parsing even messages without arguments.
spring.messages.basename=messages # Comma-separated list of basenames, each following the ResourceBundle convention.
spring.messages.cache-seconds=-1 # Loaded resource bundle files cache expiration, in seconds. When set to -1, bundles are cached forever.
spring.messages.encoding=UTF-8 # Message bundles encoding.
spring.messages.fallback-to-system-locale=true # Set whether to fall back to the system Locale if no files for a specific Locale have been found.

修改spring.messages.basename的配置:

引用

spring.messages.basename=i18n/messages_common,i18n/messages_api,i18n/messages_admin

以下文件将都会被加载

• /src/main/resources/i18n/messages_common.properties
• /src/main/resources/i18n/messages_api.properties
• /src/main/resources/i18n/messages_admin.properties

（3）页面显示（Thymeleaf）
/src/main/resources/hello.html

<h1 th:text="#{search.condition}"></h1>

（4）代码中使用

@Autowired
private MessageSource messageSource;

String msg = messageSource.getMessage("search.condition", null, locale);

a- 获取request的Locale

Controller参数注入

@RequestMapping("/sample")
public String sample(Model model, Locale locale) {
    String message = messageSource.getMessage("search.condition", null, locale);
    log.info(message);
    return "sample";
}

代码获取

Locale locale1 = LocaleContextHolder.getLocale(); // 当前request
Locale locale2 = RequestContextUtils.getLocale(request); // 指定request

b- 通用的使用

@Component
public class MessageManager {

    private static MessageSource messageSource; 

    public static String getMsg(String key) {
        Locale locale = LocaleContextHolder.getLocale();
        return messageSource.getMessage(key, null, locale);
    }

    public static String getMsg(String key, String... arg) {
        Locale locale = LocaleContextHolder.getLocale();
        Object[] args = new Object[arg.length];
        for (int i = 0; i < arg.length; i++) {
            args[i] = arg[i];
        }
        return messageSource.getMessage(key, args, locale);
    }

    @Autowired(required = true)
    public void setMessageSource(MessageSource messageSource) {
        MessageManager.messageSource = messageSource;
    }

}

String msg = MessageManager.getMsg("search.condition");

（5）设置验证信息Validator

Hibernate Validator 和 JSR 303 validation API的提示信息，默认是ValidationMessages.properties。亦可以统一到messages.properties里。

@Configuration
public class MessageConfig extends WebMvcConfigurerAdapter {
    @Autowired
    private MessageSource messageSource;

    @Bean
    public LocalValidatorFactoryBean validator() {
        LocalValidatorFactoryBean localValidatorFactoryBean = new LocalValidatorFactoryBean();
        localValidatorFactoryBean.setValidationMessageSource(messageSource);
        return localValidatorFactoryBean;
    }

    @Override
    public Validator getValidator() {
        return validator();
    }
}

（6）设置语言

默认根据浏览器的语言设置来决定显示语言AcceptHeaderLocaleResolver。一般应用多采用会话级别的语言设置SessionLocaleResolver。

@Bean
public LocaleResolver localeResolver() {
    SessionLocaleResolver sessionLocaleResolver = new SessionLocaleResolver();
    sessionLocaleResolver.setDefaultLocale(Locale.CHINA);
    return sessionLocaleResolver;
}

（7）切换语言

a- 通过Interceptor

@Bean
public LocaleChangeInterceptor localeChangeInterceptor() {
    LocaleChangeInterceptor lci = new LocaleChangeInterceptor();
    lci.setParamName("lang");
    return lci;
}
@Override
public void addInterceptors(InterceptorRegistry registry) {
    registry.addInterceptor(localeChangeInterceptor());
}

URL中通过参数lang就可以切换到不同语言。比如：http://localhost:8080/hello.html?lang=zh

b- 代码内设置语言

Locale locale = Locale.CHINA;
LocaleContextHolder.setLocale(locale);
request.getSession().setAttribute(SessionLocaleResolver.LOCALE_SESSION_ATTRIBUTE_NAME, locale);