SpringMvc 源码分析 (RequstMappingHandlerMapping的使用细节介绍) (七)

• • • 1.文字介绍
    • 2.代码介绍

由上一篇可知当DispatcherServlet初始化的时候会初始化HandlerMapping

而默认的HandlerMapping为RequestMappingHandlerMapping

这里利用代码简单介绍一下RequestMappingHandlerMapping

代码目录

Controller1.java

@RestController
public class Controller1 {
    @GetMapping("/test1")
    public String test1(){
        System.out.println("1");
        return "1";
    }
}

WebConfig.java

@ComponentScan
@PropertySource("classpath:application.properties")
@EnableConfigurationProperties({WebMvcProperties.class, ServerProperties.class})
public class WebConfig {
    @Bean
    public TomcatServletWebServerFactory tomcatServletWebServerFactory(ServerProperties serverProperties){
        return new TomcatServletWebServerFactory(serverProperties.getPort());
    }


    @Bean
    public DispatcherServlet dispatcherServlet(){
        return new DispatcherServlet();
    }

    @Bean
    public DispatcherServletRegistrationBean dispatcherServletRegistrationBean(WebMvcProperties webMvcProperties){
        DispatcherServletRegistrationBean registrationBean = new DispatcherServletRegistrationBean(dispatcherServlet(), "/");
        registrationBean.setLoadOnStartup(webMvcProperties.getServlet().getLoadOnStartup());
        return registrationBean;
    }

    @Bean
    public RequestMappingHandlerMapping requestMappingHandlerMapping(){
        return new RequestMappingHandlerMapping();
    }



}

这里是自定义了Bean, 没有利用默认的, 因为默认的逻辑虽然也创建了RequestMappingHandlerMapping, 但是作为了DispatcherServlet的一个成员变量, 没有放入到Spring的ioc容器中, 所以这里为自定义了这个Bean。

A20.java

    public static void main(String[] args) {
        AnnotationConfigServletWebServerApplicationContext context =
                new AnnotationConfigServletWebServerApplicationContext(WebConfig.class);

        RequestMappingHandlerMapping handlerMapping = context.getBean(RequestMappingHandlerMapping.class);
        // 路径信息, 控制器方法
        Map map = handlerMapping.getHandlerMethods();
        map.forEach((k, v) -> {
            System.out.println(k + " = " + v);
        });

    }

得到了Controller1的test1方法

       MockHttpServletRequest request = new MockHttpServletRequest("GET", "/test1");
        HandlerExecutionChain chain = handlerMapping.getHandler(request);
        System.out.println(chain);

这里是模拟的Get请求去请求test1路径的控制器, 生成一个链条