注解式SpringWebMvc

注解式入口（SPI）

public class MyStarterInitializer extends AbstractAnnotationConfigDispatcherServletInitializer {
    
    @Override
    protected Class[] getRootConfigClasses() {
        return new Class[]{RootConfig.class};
    }

    
    @Override
    protected Class[] getServletConfigClasses() {
        return new Class[]{WebConfig.class};
    }

    
    @Override
    protected String[] getServletMappings() {
        return new String[]{"/"};
    }
}

父容器配置

@Configuration
@ComponentScan(
        basePackages = "org.example.springmvc.annotation",
        excludeFilters ={
                @ComponentScan.Filter(type = FilterType.ANNOTATION,value = {RestController.class, Controller.class}),
                @ComponentScan.Filter(type = FilterType.ASSIGNABLE_TYPE,value = WebConfig.class)
        }
)
public class RootConfig {
}

子容器配置（按需配置）

@Configuration
@ComponentScan(
        basePackages = "org.example.springmvc.annotation",
        includeFilters = {
                @ComponentScan.Filter(type = FilterType.ANNOTATION, value = {RestController.class, Controller.class})
        }
)
@EnableWebMvc // 
public class WebConfig implements WebMvcConfigurer {
    @Bean
    public MyIntercepter myIntercepter() {
        return new MyIntercepter();
    }

    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(myIntercepter())
                .addPathPatterns("
protected void registerDispatcherServlet(ServletContext servletContext) {
     //创建子容器
     WebApplicationContext servletAppContext = this.createServletApplicationContext();
     
     //实例化DispatcherServlet
     frameworkServlet dispatcherServlet=this.createDispatcherServlet(servletAppContext);
     
    dispatcherServlet.setContextInitializers(getServletApplicationContextInitializers());

        Dynamic registration = servletContext.addServlet(servletName, dispatcherServlet);

        // 1
        registration.setLoadonStartup(1);

        registration.addMapping(this.getServletMappings());
        registration.setAsyncSupported(this.isAsyncSupported());


            Filter[] filters = this.getServletFilters();
            if (!ObjectUtils.isEmpty(filters)) {
                Filter[] var7 = filters;
                int var8 = filters.length;

                for(int var9 = 0; var9 < var8; ++var9) {
                    Filter filter = var7[var9];
                    this.registerServletFilter(servletContext, filter);
                }
            }

            this.customizeRegistration(registration);

}

 上述关键代码，实例化子父容器、Servlet、监听器。

        listenerStart()------启动父容器

        loadonStartup(findChildren()----启动子容器