SpringMVC的国际化

WebMVC的核心LocaleResolver，MessageSource。

WebMvcAutoConfiguration 是SpringBoot中的 Web方面的自动配置类。

在MVC的配置类里面，如果没有自定义的LocaleResolver，那么就会使用默认的。并且自定义的名称是"localeResolver"，才不会加载默认的。

默认使用的是AcceptHeaderLocaleResolver，这个类会从请求头里面获取Locale，如果没有，就使用默认的。

java 复制代码

@Override
@Bean
@ConditionalOnMissingBean(name = DispatcherServlet.LOCALE_RESOLVER_BEAN_NAME)
public LocaleResolver localeResolver() {
    if (this.webProperties.getLocaleResolver() == WebProperties.LocaleResolver.FIXED) {
        return new FixedLocaleResolver(this.webProperties.getLocale());
    }
    AcceptHeaderLocaleResolver localeResolver = new AcceptHeaderLocaleResolver();
    localeResolver.setDefaultLocale(this.webProperties.getLocale());
    return localeResolver;
}

@ConfigurationProperties("spring.web")
public class WebProperties {
    private Locale locale;

    private LocaleResolver localeResolver = LocaleResolver.ACCEPT_HEADER;

    private final Resources resources = new Resources();
}

默认的LocaleResolver

不需要更改，需要在请求头里面添加的Accept-Language属性。
自定义的LocaleResolver

需要从自定义的报文里面获取对应属性，就需要自定义LocaleResolver，获取报文属性里面的特定字段。

自定义实现国际化

自定义的LocaleResolver、MessageSource、Validator添加国际化功能

java 复制代码

@Configuration
public class LocaleWebMvcConfigurer implements WebMvcConfigurer {

    @Value("${spring.messages.basename:[]}")
    private String[] basename;

    @Bean
    public MessageSource messageSource() {
        ReloadableResourceBundleMessageSource messageSource =
                new ReloadableResourceBundleMessageSource();
        List<String> baseNames = new ArrayList<>();
        baseNames.add("classpath:i18n/validation/messages");
        Optional.ofNullable(basename).ifPresent(path -> {
            baseNames.addAll(Arrays.asList(path));
        });
        messageSource.setBasenames(baseNames.toArray(new String[0]));
        messageSource.setDefaultEncoding(StandardCharsets.UTF_8.name());
        return messageSource;
    }

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

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

    @Bean
    public LocaleResolver localeResolver() {
        return new CustomLocaleResolver();
    }

    private static class CustomLocaleResolver implements LocaleResolver {
        @Override
        public Locale resolveLocale(HttpServletRequest request) {
            String[] locales = Optional.ofNullable((String) FlowRuntimeContext.getTechProperty("LOCALE")).orElse(Locale.getDefault().toString()).split("_");
            return new Locale(locales[0], locales[1]);
        }

        @Override
        public void setLocale(HttpServletRequest request, HttpServletResponse response, Locale locale) {
        }
    }
}

指定类路径下添加语言包message.properties,message_zh_CN.properties,message_en_US.properties,message_zh_TW.properties
使用MessageSource获取对应的message

messageSource.getMessage(String code, @Nullable Object[] args, Locale locale);