使用 SpringBoot + kaptcha 生成、校对 验证码

一、前言

验证码这么常见，想必不用多说了。最近做项目要用到验证码，也参考了网上很多方法，唯有下面方法感觉是最简单的，使用的是 Google 的 kaptcha 框架。

二、功能演示

1、git 图说明：

①点击验证码图片会切换验证码图片

②验证码输入错误会提示输入错误，重新输入新的验证码

③输入验证码正确跳转到成功界面

三、代码

1、代码结构

2、pom

（SpringBoot+thymeleaf+web+kaptcha ）

注意引入 kaptcha 的 Maven 依赖

<!-- https://mvnrepository.com/artifact/com.github.penggle/kaptcha -->
<dependency>
<groupId>com.github.penggle</groupId>
<artifactId>kaptcha</artifactId>
<version>2.3.2</version>
</dependency>

3、KaptchaConfig

即 kaptcha 的配置文件

package com.cun.conf;

import java.util.Properties;

import org.springframework.context.annotation.Bean;
import org.springframework.stereotype.Component;

import com.google.code.kaptcha.impl.DefaultKaptcha;
import com.google.code.kaptcha.util.Config;

@Component
public class KaptchaConfig {
@Bean
public DefaultKaptcha getDefaultKaptcha() {
com.google.code.kaptcha.impl.DefaultKaptcha defaultKaptcha = new com.google.code.kaptcha.impl.DefaultKaptcha();
Properties properties = new Properties();
// 图片边框
properties.setProperty("kaptcha.border", "yes");
// 边框颜色
properties.setProperty("kaptcha.border.color", "105,179,90");
// 字体颜色
properties.setProperty("kaptcha.textproducer.font.color", "red");
// 图片宽
properties.setProperty("kaptcha.image.width", "110");
// 图片高
properties.setProperty("kaptcha.image.height", "40");
// 字体大小
properties.setProperty("kaptcha.textproducer.font.size", "30");
// session key
properties.setProperty("kaptcha.session.key", "code");
// 验证码长度
properties.setProperty("kaptcha.textproducer.char.length", "4");
// 字体
properties.setProperty("kaptcha.textproducer.font.names", "宋体,楷体,微软雅黑");
Config config = new Config(properties);
defaultKaptcha.setConfig(config);

return defaultKaptcha;
}
}

4、KaptchaController

验证码控制层

package com.cun.controller;

import java.awt.image.BufferedImage;
import java.io.ByteArrayOutputStream;

import javax.imageio.ImageIO;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.servlet.ModelAndView;

import com.google.code.kaptcha.impl.DefaultKaptcha;

@Controller
public class KaptchaController {

/**
* 1、验证码工具
*/
@Autowired
DefaultKaptcha defaultKaptcha;

/**
* 2、生成验证码
* @param httpServletRequest
* @param httpServletResponse
* @throws Exception
*/
@RequestMapping("/defaultKaptcha")
public void defaultKaptcha(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse)
throws Exception {
byte[] captchaChallengeAsJpeg = null;
ByteArrayOutputStream jpegOutputStream = new ByteArrayOutputStream();
try {
// 生产验证码字符串并保存到session中
String createText = defaultKaptcha.createText();
httpServletRequest.getSession().setAttribute("rightCode", createText);
// 使用生产的验证码字符串返回一个BufferedImage对象并转为byte写入到byte数组中
BufferedImage challenge = defaultKaptcha.createImage(createText);
ImageIO.write(challenge, "jpg", jpegOutputStream);
} catch (IllegalArgumentException e) {
httpServletResponse.sendError(HttpServletResponse.SC_NOT_FOUND);
return;
}

// 定义response输出类型为image/jpeg类型，使用response输出流输出图片的byte数组
captchaChallengeAsJpeg = jpegOutputStream.toByteArray();
httpServletResponse.setHeader("Cache-Control", "no-store");
httpServletResponse.setHeader("Pragma", "no-cache");
httpServletResponse.setDateHeader("Expires", 0);
httpServletResponse.setContentType("image/jpeg");
ServletOutputStream responseOutputStream = httpServletResponse.getOutputStream();
responseOutputStream.write(captchaChallengeAsJpeg);
responseOutputStream.flush();
responseOutputStream.close();
}

/**
* 3、校对验证码
* @param httpServletRequest
* @param httpServletResponse
* @return
*/
@RequestMapping("/imgvrifyControllerDefaultKaptcha")
public ModelAndView imgvrifyControllerDefaultKaptcha(HttpServletRequest httpServletRequest,
HttpServletResponse httpServletResponse) {
ModelAndView andView = new ModelAndView();
String rightCode = (String) httpServletRequest.getSession().getAttribute("rightCode");
String tryCode = httpServletRequest.getParameter("tryCode");
System.out.println("rightCode:"+rightCode+" ———— tryCode:"+tryCode);
if (!rightCode.equals(tryCode)) {
andView.addObject("info", "错误的验证码");
andView.setViewName("index");
} else {
andView.addObject("info", "登录成功");
andView.setViewName("success");
}
return andView;
}

@RequestMapping("/toIndex")
public String toIndex() {
return "index";
}
}

5、application.yml SpringBoot 核心配置文件

server:
port: 80
context-path: /

6、主界面 index.html

<!DOCTYPE html>
<!-- thymeleaf 提示功能 -->
<html xmlns:th="http://www.thymeleaf.org">
<head lang="en">
<meta charset="UTF-8"></meta>
<title>hello</title>
<!-- 引入BootStrap -->
<link rel="stylesheet" href="../bootstrap3/css/bootstrap-theme.min.css" />
<link rel="stylesheet" href="../bootstrap3/css/bootstrap.min.css" />
<script type="text/javascript" src="../bootstrap3/js/jquery-1.11.2.min.js"></script>
<script type="text/javascript" src="../bootstrap3/js/bootstrap.min.js"></script>
</head>
<style type="text/css">
body {
padding: 10px
}
</style>
<body>
<!-- 提示 -->
<h3 th:text="${info}"></h3>
<div>
<!-- 后面添加参数起到清除缓存作用 -->
<img alt="验证码" onclick="this.src='/defaultKaptcha?d='+new Date()*1" src="/defaultKaptcha" />
</div>
<form action="imgvrifyControllerDefaultKaptcha" >
<input type="text" name="tryCode" />
<input type="submit" value="提交" class="btn btn-success"></input>
</form>
</body>
</html>

7、验证成功界面 success.html

<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8"></meta>
<title>验证成功</title>
</head>
<body>
<h1>验证成功</h1>
</body>
</html>

三、小结

1、参考文章

①springboot 集成kaptcha验证码简单实例

②Kaptchar详细配置表

2、感受

验证码这种东西，一切都是固定套路，会用就行