在AbstractHandlerMethodMapping类中，获取HandlerMethods。

public void afterPropertiesSet() {
        this.initHandlerMethods();
    }

    protected void initHandlerMethods() {
        if(this.logger.isDebugEnabled()) {
            this.logger.debug("Looking for request mappings in application context: " + this.getApplicationContext());
        }
        /*获取所有bean形成列表，后续将会遍历这些bean*/
        String[] beanNames = this.detectHandlerMethodsInAncestorContexts?BeanFactoryUtils.beanNamesForTypeIncludingAncestors(this.getApplicationContext(), Object.class):this.getApplicationContext().getBeanNamesForType(Object.class);
        String[] var2 = beanNames;
        int var3 = beanNames.length;

        for(int var4 = 0; var4 < var3; ++var4) {
            String beanName = var2[var4];
            /*通过isHandler函数，检查是否是Controller和RequestMapping注解。它是通过AnnotationUtils和ClassUtils静态类遍历的*/
            if(!beanName.startsWith("scopedTarget.") && this.isHandler(this.getApplicationContext().getType(beanName))) {
                this.detectHandlerMethods(beanName);
            }
        }
        /*获取所有requestMapping对象完成注册的最后一步。*/
        this.handlerMethodsInitialized(this.getHandlerMethods());
    }

在该函数中检查局部变量

在AbstractHandlerMethodMapping的派生类中，即RequestMappingHandlerMapping中，实现了isHandler的类型判断。

在getHandlerMethods中

public Map getHandlerMethods() {
        return Collections.unmodifiableMap(this.handlerMethods);
    }

此外，附加findall代码。

@Controller
@RequestMapping("/demo")
public class DemoController {

	@RequestMapping("/findall")
	public String handleList(Model model) {
		logger.info("demo02  handleList");
		List list = demoService.findAll();
		model.addAttribute("results", list);
		return "demo";
	}
}



@Controller("/demo_servlet2")
public class Demo2Servlet extends HttpServlet {	
	@PostConstruct  //init-method="init"
	@Override
	public void init() throws ServletException {
		// TODO Auto-generated method stub
		logger.info("Demo2Servlet init start");		
		
		logger.info("Demo2Servlet init end");
	}

	@RequestMapping("/findall")
	public String handleList(Model model) {
		logger.info("demo02  handleList");
		return "demo";
	}

	@Override
	protected void service(HttpServletRequest req, HttpServletResponse response)
			throws ServletException, IOException {
		// TODO Auto-generated method stub

		logger.info("Demo2Servlet service start");

		response.setContentType(CONTENT_TYPE);
		response.setHeader("Pragma", "No-cache");
		response.setHeader("Cache-Control", "no-cache");
		response.setDateHeader("Expires", 0);
		String result = demoService.getById(1l).getName();
		//Integer.valueOf(result); //测试异常显示页面
		PrintWriter out = response.getWriter();
		out.println("");
		out.println("\n");
		out.println("" + result + "\n");
		out.println("\n");

		out.flush();
		out.close();

		logger.info("Demo2Servlet service end");
	}

	@PreDestroy //destroy-method="destroy"
	@Override
	public void destroy() {
		// TODO Auto-generated method stub
		logger.info("Demo2Servlet destroy start");
		
		logger.info("Demo2Servlet destroy end");
	}
	
}