今天让我们来看看另一个重要的类:WebMvcAutoConfigurationAdapter。先来看看它的声明:
@Configuration
@Import(EnableWebMvcConfiguration.class)
@EnableConfigurationProperties({ WebMvcProperties.class, ResourceProperties.class })
@Order(0)
public static class WebMvcAutoConfigurationAdapter implements WebMvcConfigurer, ResourceLoaderAware {
很显然,它也是SpringBoot的一个配置类,@Improt注解是被用来整合所有在@Configuration注解中定义的bean配置。这其实很像我们将多个XML配置文件导入到单个文件的情形。@Import注解实现了相同的功能。
再往下看可以看到SpringBoot中常见的viewResolver
@Bean
@ConditionalOnMissingBean
public InternalResourceViewResolver defaultViewResolver() {
InternalResourceViewResolver resolver = new InternalResourceViewResolver();
resolver.setPrefix(this.mvcProperties.getView().getPrefix());
resolver.setSuffix(this.mvcProperties.getView().getSuffix());
return resolver;
}
@Bean
@ConditionalOnBean(View.class)
@ConditionalOnMissingBean
public BeanNameViewResolver beanNameViewResolver() {
BeanNameViewResolver resolver = new BeanNameViewResolver();
resolver.setOrder(Ordered.LOWEST_PRECEDENCE - 10);
return resolver;
}
@Bean
@ConditionalOnBean(ViewResolver.class)
@ConditionalOnMissingBean(name = "viewResolver", value = ContentNegotiatingViewResolver.class)
public ContentNegotiatingViewResolver viewResolver(BeanFactory beanFactory) {
ContentNegotiatingViewResolver resolver = new ContentNegotiatingViewResolver();
resolver.setContentNegotiationManager(
beanFactory.getBean(ContentNegotiationManager.class));
// ContentNegotiatingViewResolver uses all the other view resolvers to locate
// a view so it should have a high precedence
resolver.setOrder(Ordered.HIGHEST_PRECEDENCE);
return resolver;
}
接着往下看,可以看到这个是配置区域的。@ConditionalOnProperty表示如果在application.properties中配置了spring.mvc.locale属性,则该配置会生效。
@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;
}
再往下看是配置静态资源(包括/webjars/**,classpath:/META-INF/resources/webjars/")和favicon(可以通过在application.properties中设置spring.mvc.favicon.enabled来启用或禁用)
好了,文章到这里就结束了,静态资源这一块并没有什么特别的地方。我们需要理解的是这几个注解的用法,还有使用了配置属性,可以允许用户对其进行自定义。还有一个值得提一下,默认的地域解析器只会处理一个地域,通过上面提到的spring.mvc.locale来配置。