Hướng dẫn và ví dụ Spring Boot Interceptor

public boolean preHandle(HttpServletRequest request,
                         HttpServletResponse response,
                         Object handler)


public void postHandle(HttpServletRequest request,
                       HttpServletResponse response,
                       Object handler,
                       ModelAndView modelAndView)


public void afterCompletion(HttpServletRequest request,
                            HttpServletResponse response,
                            Object handler,
                            Exception ex)

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>org.o7planning</groupId>
    <artifactId>SpringBootInterceptor</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>SpringBootInterceptor</name>
    <description>Spring Boot + Interceptor</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.0.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-thymeleaf</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>


</project>

package org.o7planning.sbinterceptor;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class SpringBootInterceptorApplication {

    public static void main(String[] args) {
        SpringApplication.run(SpringBootInterceptorApplication.class, args);
    }
    
}

package org.o7planning.sbinterceptor.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.sbinterceptor.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.sbinterceptor.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.sbinterceptor.config;

import org.o7planning.sbinterceptor.interceptor.AdminInterceptor;
import org.o7planning.sbinterceptor.interceptor.LogInterceptor;
import org.o7planning.sbinterceptor.interceptor.OldLoginInterceptor;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;

@Configuration
public class WebMvcConfig extends WebMvcConfigurerAdapter {

	// 
	@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.sbinterceptor.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";
	}

}

<!DOCTYPE HTML>
<html xmlns:th="http://www.thymeleaf.org">

   <head>
      <meta charset="UTF-8" />
      <title>Spring Boot Mvc Interceptor example</title>
   </head>

   <body>
      <div style="border: 1px solid #ccc;padding: 5px;margin-bottom:10px;">
         <a th:href="@{/}">Home</a>
         &nbsp;&nbsp; | &nbsp;&nbsp;
         <a th:href="@{/admin/oldLogin}">/admin/oldLogin (OLD URL)</a>  
      </div>

      <h3>Spring Boot Mvc Interceptor</h3>
      
      <span style="color:blue;">Testing LogInterceptor</span>
      <br/><br/>

      See Log in Console..

   </body>
</html>

<!DOCTYPE HTML>
<html xmlns:th="http://www.thymeleaf.org">
   <head>
      <meta charset="UTF-8" />
      <title>Spring Boot Mvc Interceptor example</title>
   </head>
   <body>
   
      <div style="border: 1px solid #ccc;padding: 5px;margin-bottom:10px;">
         <a th:href="@{/}">Home</a>
         &nbsp;&nbsp; | &nbsp;&nbsp;
         <a th:href="@{/admin/oldLogin}">/admin/oldLogin (OLD URL)</a>  
      </div>
      
      <h3>This is Login Page</h3>
      
      <span style="color:blue">Testing OldLoginInterceptor &amp; AdminInterceptor</span>
      <br/><br/>
      See more info in the Console.
      
   </body>
   
</html>