Captcha in Spring MVC Framework

This project will demonstrate how to create Captcha in Spring MVC Framework

  • SpringMVCFramework
    • src/main/java
      • com.demo
        • SpringMVCFramework.java
      • com.demo.controllers
        • AccountController.java
        • CaptchaController.java
      • com.demo.entities
        • Account.java
    • src/main/resources
      • static
      • templates
      • application.properties
    • src
      • main
        • webapp
          • WEB-INF
            • views
              • account
                • index.jsp
                • success.jsp
    • pom.xml
package com.demo;
    
    import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    
    @SpringBootApplication
    public class SpringMVCFramework {
    
        public static void main(String[] args) {
            SpringApplication.run(SpringMVCFramework.class, args);
        }
    }
package com.demo.controllers;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.*;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.io.OutputStream;
import java.util.Random;
import javax.imageio.ImageIO;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

@Controller
@RequestMapping("captcha")
public class CaptchaController {

    @RequestMapping(method = RequestMethod.GET)
    public void index(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        response.setContentType("image/jpg");
        int iTotalChars = 6;
        int iHeight = 40;
        int iWidth = 150;
        Font fntStyle1 = new Font("Arial", Font.BOLD, 30);
        Random randChars = new Random();
        String sImageCode = (Long.toString(Math.abs(randChars.nextLong()), 36)).substring(0, iTotalChars);
        BufferedImage biImage = new BufferedImage(iWidth, iHeight, BufferedImage.TYPE_INT_RGB);
        Graphics2D g2dImage = (Graphics2D) biImage.getGraphics();
        int iCircle = 15;
        for (int i = 0; i < iCircle; i++) {
            g2dImage.setColor(new Color(randChars.nextInt(255), randChars.nextInt(255), randChars.nextInt(255)));
        }
        g2dImage.setFont(fntStyle1);
        for (int i = 0; i < iTotalChars; i++) {
            g2dImage.setColor(new Color(randChars.nextInt(255), randChars.nextInt(255), randChars.nextInt(255)));
            if (i % 2 == 0) {
                g2dImage.drawString(sImageCode.substring(i, i + 1), 25 * i, 24);
            } else {
                g2dImage.drawString(sImageCode.substring(i, i + 1), 25 * i, 35);
            }
        }
        OutputStream osImage = response.getOutputStream();
        ImageIO.write(biImage, "jpeg", osImage);
        g2dImage.dispose();
        HttpSession session = request.getSession();
        session.setAttribute("captcha_security", sImageCode);
    }

}
package com.demo.controllers;

import com.demo.entities.Account;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
import org.springframework.stereotype.Controller;
import org.springframework.ui.ModelMap;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;

@Controller
@RequestMapping("account")
public class AccountController {

    @RequestMapping(method = RequestMethod.GET)
    public String index(ModelMap modelMap) {
        modelMap.put("account", new Account());
        return "account/index";
    }

    @RequestMapping(value = "save", method = RequestMethod.POST)
    public String save(@ModelAttribute("account") Account account, HttpSession session, HttpServletRequest request,
            ModelMap modelMap) {
        String captcha = session.getAttribute("captcha_security").toString();
        String verifyCaptcha = request.getParameter("captcha");
        if (captcha.equals(verifyCaptcha)) {
            modelMap.put("account", account);
            return "account/success";
        } else {
            modelMap.put("error", "Captcha Invalid");
            return "account/index";
        }
    }

}
package com.demo.entities;

public class Account {

    private String username;
    private String password;
    private String captcha;

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public String getCaptcha() {
        return captcha;
    }

    public void setCaptcha(String captcha) {
        this.captcha = captcha;
    }

}
spring.mvc.view.prefix = /WEB-INF/views/
spring.mvc.view.suffix = .jsp
spring.mvc.static-path-pattern=/resources/**

server.port=9596
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
<%@ taglib prefix="s" uri="http://www.springframework.org/tags/form" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Register Account</title>
</head>
<body>

    <h3>Register Account</h3>
    <s:form method="post" modelAttribute="account"
        action="${pageContext.request.contextPath }/account/save">
        <table>
            <tr>
                <td>Username</td>
                <td>
                    <s:input path="username" required="required"/>
                </td>
            </tr>
            <tr>
                <td>Password</td>
                <td>
                    <s:password path="password" required="required"/>
                </td>
            </tr>
            <tr>
                <td>Captcha</td>
                <td>
                    <img src="${pageContext.request.contextPath }/captcha">
                    <br>
                    <input type="text" name="captcha" required="required" style="margin-top: 5px;">
                    <br>
                    ${error }
                </td>
            </tr>
            <tr>
                <td>&nbsp;</td>
                <td>
                    <input type="submit" value="Save">
                </td>
            </tr>
        </table>
    </s:form>

</body>
</html>
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Success</title>
</head>
<body>

    <h3>Account Info</h3>
    Username: ${account.username }
    <br> Password: ${account.password }

</body>
</html>
<?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>com.demo</groupId>
    <artifactId>LearnSpringMVCWithRealApps</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>LearnSpringMVCWithRealApps</name>
    <description>Learn Spring MVC with Real Apps</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.5.2.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>

        <!-- Spring MVC  -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <!-- JSTL tag lib -->
        <dependency>
            <groupId>javax.servlet.jsp.jstl</groupId>
            <artifactId>javax.servlet.jsp.jstl-api</artifactId>
            <version>1.2.1</version>
        </dependency>

        <dependency>
            <groupId>taglibs</groupId>
            <artifactId>standard</artifactId>
            <version>1.1.2</version>
        </dependency>

        <!-- Tomcat for JSP rendering -->
        <dependency>
            <groupId>org.apache.tomcat.embed</groupId>
            <artifactId>tomcat-embed-jasper</artifactId>
            <scope>provided</scope>
        </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>

Screenshots