SpringMVC原理解读

请求参数源码

最底层实际上是调用了request.getParameterValues方法

@PathVariable注解

拦截器源码

 HandlerAdapter ha = this.getHandlerAdapter(mappedHandler.getHandler());
                String method = request.getMethod();
                boolean isGet = "GET".equals(method);
                if (isGet || "HEAD".equals(method)) {
                    long lastModified = ha.getLastModified(request, mappedHandler.getHandler());
                    if (this.logger.isDebugEnabled()) {
                        this.logger.debug("Last-Modified value for [" + getRequestUri(request) + "] is: " + lastModified);
                    }

                    if ((new ServletWebRequest(request, response)).checkNotModified(lastModified) && isGet) {
                        return;
                    }
                }

                if (!mappedHandler.applyPreHandle(processedRequest, response)) {
                    return;
                }

                mv = ha.handle(processedRequest, response, mappedHandler.getHandler());
                if (asyncManager.isConcurrentHandlingStarted()) {
                    return;
                }

点进去看看

    boolean applyPreHandle(HttpServletRequest request, HttpServletResponse response) throws Exception {
        HandlerInterceptor[] interceptors = this.getInterceptors();
        if (!ObjectUtils.isEmpty(interceptors)) {
            for(int i = 0; i < interceptors.length; this.interceptorIndex = i++) {
                HandlerInterceptor interceptor = interceptors[i];
                if (!interceptor.preHandle(request, response, this.handler)) {
                    this.triggerAfterCompletion(request, response, (Exception)null);
                    return false;
                }
            }
        }

        return true;
    }

最后调用完jsp的视图之后，才调用这个