SpringBoot kaptcha 生成验证码

SpringBoot kaptcha 验证码
验证码生成使用的是 Google 的 kaptcha 框架，固定的代码，只需要自己配置一些参数即可，下面的代码是主要的代码，像项目的前端代码、验证生成的验证码之类的代码没有给出。

pom

需要引入 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>

KaptchaConfig

即 kaptcha 的配置文件

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", "no");
        // 边框颜色
        properties.setProperty("kaptcha.border.color", "105,179,90");
        // 字体颜色
        properties.setProperty("kaptcha.textproducer.font.color", "black");
        // 图片宽
        properties.setProperty("kaptcha.image.width", "120");
        // 图片高
        properties.setProperty("kaptcha.image.height", "50");
        // 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", "5");
        // 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;
    }
}

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 {
    //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();
    }
}

效果

访问localhost:8080//defaultKaptcha（不同的端口不同访问链接）