博客

应用场景 ,

​ WebMvcAutoConfiguration:中

@Bean
   	@ConditionalOnMissingBean
   	@ConditionalOnProperty(prefix = "spring.mvc", name = "locale")
   	public LocaleResolver localeResolver() {
   		if (this.mvcProperties
   				.getLocaleResolver() == WebMvcProperties.LocaleResolver.FIXED) {
   			return new FixedLocaleResolver(this.mvcProperties.getLocale());
   		}
   		AcceptHeaderLocaleResolver localeResolver = new AcceptHeaderLocaleResolver();
   		localeResolver.setDefaultLocale(this.mvcProperties.getLocale());
   		return localeResolver;
   	}

​ @ConditionalOnMissingBean注解:代表的是在容器中是否有这个bean , bean的id是

localeResolver , 要想自己自定义的方法能够覆盖 系统中的默认配置 , 则需要的是配置的方法类型和名称都需要和默认配置的方法产生一致 .

​ 也就是之前xml配置中的class 和id一致 …

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