问request.getRequestURI总是返回"/error“

EN

package com.controller;

import com.model.UserDao;
import com.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.SessionAttributes;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;

@Controller
@RequestMapping(value = "/signin")
@SessionAttributes("username")
public class LoginViewController {
    @Autowired
    private UserService userService;

    @RequestMapping(method = RequestMethod.GET)
    public ModelAndView showLoginForm(){
        return new ModelAndView("login");
    }

    @RequestMapping(method = RequestMethod.POST)
    public ModelAndView verifyLogin(HttpServletRequest request, HttpSession session) {
        ModelAndView modelAndView;
        String username = request.getParameter("username");
        // if login fails, set reload login page
        if (userService.verifyUserLogin(username,request.getParameter("password")) == null){
            modelAndView = new ModelAndView("login");
            modelAndView.addObject("login_failed", true);
        } else {
            modelAndView = new ModelAndView("index");
            session.setAttribute("username", username);
        }
        return modelAndView;
    }
}

package com.spring.interceptor;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import java.util.ArrayList;

public class AccessInterceptor implements HandlerInterceptor {
    @Override
    public boolean preHandle(
            HttpServletRequest request,
            HttpServletResponse response,
            Object handler) throws Exception {
        System.out.println(request.getRequestURI());

        try {
            if (!request.getRequestURI().endsWith("/signin")) {
                if (request.getSession()
                        .getAttribute("username") == null) {
                    response.sendRedirect(request.getContextPath() + "/signin");
                    return false;
                }

            }
        } catch (Exception e) {
            System.out.println(e.getMessage());
        }
        return true;
    }

    @Override
    public void postHandle(HttpServletRequest request,
                           HttpServletResponse response, Object handler,
                           ModelAndView modelAndView) throws Exception {
        System.out.println("Post-handle");
    }

    @Override
    public void afterCompletion(HttpServletRequest request,
                                HttpServletResponse response, Object handler, Exception ex)
            throws Exception {
        System.out.println("After completion handle");
    }
}

package com.spring;

import com.spring.interceptor.AccessInterceptor;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.*;

@Configuration
@EnableWebMvc
public class WebApplicationConfig extends WebMvcConfigurerAdapter {

    @Override
    public void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) {
        configurer.enable();
    }

    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(
                new AccessInterceptor()).
                addPathPatterns("/**").
                excludePathPatterns("/signin/**").
                excludePathPatterns("/static/**");
    }

    @Override
    public void addResourceHandlers(ResourceHandlerRegistry registry) {
        registry.addResourceHandler("/resources/**").addResourceLocations("/resources/");
    }

}

package com.spring;

import org.springframework.web.WebApplicationInitializer;
import org.springframework.web.context.ContextLoaderListener;
import org.springframework.web.context.support.AnnotationConfigWebApplicationContext;
import org.springframework.web.servlet.DispatcherServlet;

import javax.servlet.ServletContext;
import javax.servlet.ServletRegistration;

public class MyWebAppInitializer implements WebApplicationInitializer {

    @Override
    public void onStartup(ServletContext container) {
        // Create the 'root' Spring application context
        AnnotationConfigWebApplicationContext rootContext =
                new AnnotationConfigWebApplicationContext();
        rootContext.register(WebApplicationConfig.class);

        // Manage the lifecycle of the root application context
        container.addListener(new ContextLoaderListener(rootContext));

        // Create the dispatcher servlet's Spring application context
        AnnotationConfigWebApplicationContext dispatcherContext =
                new AnnotationConfigWebApplicationContext();
        dispatcherContext.register(MyWebAppInitializer.class);

        // Register and map the dispatcher servlet
        ServletRegistration.Dynamic dispatcher = container.addServlet("dispatcherServlet", new DispatcherServlet(rootContext));
        dispatcher.setLoadOnStartup(1);
        dispatcher.addMapping("/*");
        dispatcher.addMapping("*.css");
        dispatcher.addMapping("*.eot");
        dispatcher.addMapping("*.svg");
        dispatcher.addMapping("*.ttf");
        dispatcher.addMapping("*.woff");
        dispatcher.addMapping("*.map");
        dispatcher.addMapping("*.js");
        dispatcher.addMapping("*.ico");
    }

}