Hướng dẫn sử dụng Spring MVC Interceptor

package org.o7planning.springmvcinterceptor.config;

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

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

public class SpringWebAppInitializer implements WebApplicationInitializer {

    @Override
    public void onStartup(ServletContext servletContext) throws ServletException {
        AnnotationConfigWebApplicationContext appContext = new AnnotationConfigWebApplicationContext();
        appContext.register(ApplicationContextConfig.class);

        ServletRegistration.Dynamic dispatcher = servletContext.addServlet("SpringDispatcher",
                new DispatcherServlet(appContext));
        dispatcher.setLoadOnStartup(1);
        dispatcher.addMapping("/");
    }

}

package org.o7planning.springmvcinterceptor.config;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.view.InternalResourceViewResolver;

@Configuration

@ComponentScan("org.o7planning.springmvcinterceptor.*")
public class ApplicationContextConfig {

    @Bean(name = "viewResolver")
    public InternalResourceViewResolver getViewResolver() {
        InternalResourceViewResolver viewResolver = new InternalResourceViewResolver();

        viewResolver.setPrefix("/WEB-INF/pages/");
        viewResolver.setSuffix(".jsp");

        return viewResolver;
    }
 
}

package org.o7planning.springmvcinterceptor.config;

import org.o7planning.springmvcinterceptor.interceptor.AdminInterceptor;
import org.o7planning.springmvcinterceptor.interceptor.LogInterceptor;
import org.o7planning.springmvcinterceptor.interceptor.OldLoginInterceptor;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.DefaultServletHandlerConfigurer;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;

@Configuration
@EnableWebMvc
public class WebMvcConfig extends WebMvcConfigurerAdapter {

 
   // Cấu hình để sử dụng các file nguồn tĩnh (html, image, ..)
   @Override
   public void addResourceHandlers(ResourceHandlerRegistry registry) {

   }

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

   //
   @Override
   public void addInterceptors(InterceptorRegistry registry) {
   
       // LogInterceptor áp dụng cho mọi URL.
       registry.addInterceptor(new LogInterceptor());
 
       // Đường dẫn login cũ, không còn sử dụng nữa.
       // Sử dụng OldURLInterceptor để điều hướng tới một URL mới.
       registry.addInterceptor(new OldLoginInterceptor())//
               .addPathPatterns("/admin/oldLogin");

 
       // Interceptor này áp dụng cho các URL có dạng /admin/*
       // Loại đi trường hợp /admin/oldLogin
       registry.addInterceptor(new AdminInterceptor())//
               .addPathPatterns("/admin/*")//
               .excludePathPatterns("/admin/oldLogin");
   }

}

package org.o7planning.springmvcinterceptor.interceptor;

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

import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;

public class LogInterceptor extends HandlerInterceptorAdapter {

   @Override
   public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
           throws Exception {
       long startTime = System.currentTimeMillis();
       System.out.println("\n-------- LogInterception.preHandle --- ");
       System.out.println("Request URL: " + request.getRequestURL());
       System.out.println("Start Time: " + System.currentTimeMillis());

       request.setAttribute("startTime", startTime);
       
       return true;
   }

   @Override
   public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler,
           ModelAndView modelAndView) throws Exception {
       System.out.println("\n-------- LogInterception.postHandle --- ");
       System.out.println("Request URL: " + request.getRequestURL());
 
       // Ở đây, bạn có thể add các attribute vào modelAndView
       // Và sử dụng nó trong các View (jsp,..)
   }

   @Override
   public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex)
           throws Exception {
       System.out.println("\n-------- LogInterception.afterCompletion --- ");

       long startTime = (Long) request.getAttribute("startTime");
       long endTime = System.currentTimeMillis();
       System.out.println("Request URL: " + request.getRequestURL());
       System.out.println("End Time: " + endTime);

       System.out.println("Time Taken: " + (endTime - startTime));
   }

}

package org.o7planning.springmvcinterceptor.interceptor;

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

import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;

public class OldLoginInterceptor extends HandlerInterceptorAdapter {

   @Override
   public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
           throws Exception {

       System.out.println("\n-------- OldLoginInterceptor.preHandle --- ");
       System.out.println("Request URL: " + request.getRequestURL());
       System.out.println("Sorry! This URL is no longer used, Redirect to /admin/login");
 
       response.sendRedirect(request.getContextPath()+"/admin/login");
       return false;
   }

   @Override
   public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler,
           ModelAndView modelAndView) throws Exception {
     
  
       // Đoạn code này sẽ không được chạy.
       System.out.println("\n-------- OldLoginInterceptor.postHandle --- ");
   }

   @Override
   public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex)
           throws Exception {
   
       // Đoạn code này sẽ không được chạy.      
       System.out.println("\n-------- QueryStringInterceptor.afterCompletion --- ");
   }

}

package org.o7planning.springmvcinterceptor.interceptor;

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

import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;

public class AdminInterceptor extends HandlerInterceptorAdapter {

    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
            throws Exception {

        System.out.println("\n-------- AdminInterceptor.preHandle --- ");
        return true;
    }

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

    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex)
            throws Exception {
        System.out.println("\n-------- AdminInterceptor.afterCompletion --- ");
    }

}

package org.o7planning.springmvcinterceptor.controller;

import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;

@Controller
public class MainController {

  @RequestMapping(value = { "/", "/test" })
  public String test(Model model) {

      System.out.println("\n-------- MainController.test --- ");

      System.out.println(" ** You are in Controller ** ");

      return "test";
  }


  // Đường dẫn này không còn sử dụng nữa.
  // Nó sẽ bị chuyển hướng bởi OldLoginInterceptor
  @Deprecated
  @RequestMapping(value = { "/admin/oldLogin" })
  public String oldLogin(Model model) {

      // Code ở đây không bao giờ được chạy.

      return "oldLogin";
  }

  @RequestMapping(value = { "/admin/login" })
  public String login(Model model) {

      System.out.println("\n-------- MainController.login --- ");

      System.out.println(" ** You are in Controller ** ");

      return "login";
  }

}