// 核心數(shù)據(jù)結(jié)構(gòu)
public class RequestMappingHandlerMapping {
    // 保存URL與處理器方法的映射關(guān)系
    private final Map<RequestMappingInfo, HandlerMethod> mappingLookup;
}
// 映射示例
mappingLookup = {
    RequestMappingInfo{
        patterns=/users/{id},    // URL模式
        methods=GET,             // HTTP方法
        params=[],              // 請(qǐng)求參數(shù)
        headers=[]              // 請(qǐng)求頭
    } -> HandlerMethod{UserController.getUser()}
}

public class HandlerExecutionChain {
    // Handler本身（如Controller的方法）
    private final Object handler;
    // 與Handler關(guān)聯(lián)的攔截器列表
    private List<HandlerInterceptor> interceptors;
}

// 處理@RequestMapping注解的方法
public class RequestMappingHandlerAdapter implements HandlerAdapter {
    public ModelAndView handle(request, response, handler) {
        // 1. 解析請(qǐng)求參數(shù)
        Object[] args = resolveParameters(request, handler);
        // 2. 調(diào)用Controller方法
        Object returnValue = invokeMethod(handler, args);
        // 3. 處理返回值
        return processReturnValue(returnValue);
    }
}

// 1. @RestController（JSON渲染）
@GetMapping("/api/user")
public User getUser() {
    return user;  // 自動(dòng)轉(zhuǎn)換為JSON
}
// 2. @Controller（HTML渲染）
@GetMapping("/user")
public String user(Model model) {
    model.addAttribute("user", user);
    return "userView";  // 解析為具體視圖
}

public class LogInterceptor implements HandlerInterceptor {
    @Override
    public boolean preHandle(request, response, handler) {
        System.out.println("LogInterceptor - preHandle");
        return true;
    }
    @Override
    public void postHandle(request, response, handler, mv) {
        System.out.println("LogInterceptor - postHandle");
    }
    @Override
    public void afterCompletion(request, response, handler, ex) {
        System.out.println("LogInterceptor - afterCompletion");
    }
}

Filter1 - 請(qǐng)求處理
    Filter2 - 請(qǐng)求處理
        LogInterceptor - preHandle
            SecurityInterceptor - preHandle
                Controller方法執(zhí)行
            SecurityInterceptor - postHandle
        LogInterceptor - postHandle
        視圖渲染
            SecurityInterceptor - afterCompletion
        LogInterceptor - afterCompletion
    Filter2 - 響應(yīng)處理
Filter1 - 響應(yīng)處理

// 1. preHandle調(diào)用（正序）
for (HandlerInterceptor interceptor : interceptors) {
    if (!interceptor.preHandle(request, response, handler)) {
        triggerAfterCompletion(request, response, handler, null);
        return false;
    }
}
// 2. postHandle調(diào)用（逆序）
for (int i = interceptors.length - 1; i >= 0; i--) {
    interceptors[i].postHandle(requestresponse, handler, mv);
}
// 3. afterCompletion調(diào)用（逆序）
for (int i = interceptors.length - 1; i >= 0; i--) {
    interceptors[i].afterCompletion(request, response, handler, ex);
}