springboot验证码整合

    @ApiOperation("用于生成带六位数字验证码并发送邮件")
    @PostMapping(value = "/captcha")
    public AjaxResult captchacode(HttpSession session,@RequestBody CaptchaReqDto captchaReqDto) throws Exception {
        //返回验证码和图片的map
        String strEnsure = Captcha.getImageCode();
        session.setAttribute("simpleCaptcha", strEnsure);
        session.setAttribute("codeTime",System.currentTimeMillis());
        if(StringUtils.isBlank(captchaReqDto.getUsername())){
            return AjaxResult.error("请输入用户名");
        }
        User user = userService.selectUserByUserid(captchaReqDto.getUsername());
        if(user == null){
            return AjaxResult.error("用户不存在");
        }
        if(StringUtils.isBlank(user.getEmail())){
            return AjaxResult.error("请联系管理员维护邮箱信息");
        }
        MailLog mailLog = new MailLog();
        mailLog.setContent(strEnsure);
        mailLog.setCreateTime(new Date());
        mailLog.setEmail(user.getEmail());
        mailLog.setToMan(captchaReqDto.getUsername());
        return mailLogService.loginMail(mailLog);
    }

    @ApiOperation("前端用户输入返回的验证码")
    @PostMapping(value = "/verify")
    public AjaxResult checkcode(HttpSession session,
                                @RequestBody CaptchaReqDto captchaReqDto) throws Exception {

        String checkCode = captchaReqDto.getCaptcha();
        // 获得验证码对象
        Object cko = session.getAttribute("simpleCaptcha");
        if (cko == null) {
            return AjaxResult.error("请输入验证码！");
        }
        String captcha = cko.toString();
        // 判断验证码输入是否正确
        if (StringUtils.isEmpty(checkCode) || captcha == null || !(checkCode.equalsIgnoreCase(captcha))) {
            return AjaxResult.error("验证码错误，请重新输入！");
        } else {
            Long codeTime = Long.valueOf(session.getAttribute("codeTime") + "");
            if ((System.currentTimeMillis() - codeTime) / 1000 / 60 > Long.valueOf(minutes)-1) {
                return AjaxResult.error("验证码已失效，请重新输入！");
            }
            return AjaxResult.success("验证通过！");
        }
    }

spring: 
  # 发送邮件配置
  mail:
   minutes: 2 # 邮件验证码失效时间，单位为分钟

import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.OutputStream;import java.util.HashMap;
import java.util.Map;import java.util.Random;

public class Captcha {
    private static char mapTable[] = {
            '0', '1', '2', '3', '4', '5',
            '6', '7', '8', '9', '0', '1',
            '2', '3', '4', '5', '6', '7',
            '8', '9'};
    public static Map getImageCode(int width, int height, OutputStream os) {
        Map returnMap = new HashMap();
        if (width <= 0) {
            width = 60;
        }
        if (height <= 0) {
            height = 20;
        }
        BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
        // 获取图形上下文
        Graphics g = image.getGraphics();
        //生成随机类
        Random random = new Random();
        // 设定背景色
        g.setColor(getRandColor(200, 250));
        g.fillRect(0, 0, width, height);
        //设定字体
        g.setFont(new Font("Times New Roman", Font.PLAIN, 18));
        // 随机产生168条干扰线，使图象中的认证码不易被其它程序探测到
        g.setColor(getRandColor(160, 200));
        for (int i = 0; i < 168; i++) {
            int x = random.nextInt(width);
            int y = random.nextInt(height);
            int xl = random.nextInt(12);
            int yl = random.nextInt(12);
            g.drawLine(x, y, x + xl, y + yl);
        }
        //取随机产生的码
        String strEnsure = "";
        //6代表6位验证码,如果要生成更多位的认证码,则加大数值
        for (int i = 0; i < 6; ++i) {
            strEnsure += mapTable[(int) (mapTable.length * Math.random())];
            // 直接生成
            String str = strEnsure.substring(i, i + 1);
            // 设置随便码在背景图图片上的位置
            g.drawString(str, 13 * i + 20, 25);
        }
        // 释放图形上下文
        g.dispose();
        returnMap.put("image",image);
        returnMap.put("strEnsure",strEnsure);
        return returnMap;
    }
    public static String getImageCode() {
        //生成随机类
        Random random = new Random();
        //取随机产生的码
        String strEnsure = "";
        //6代表6位验证码,如果要生成更多位的认证码,则加大数值
        for (int i = 0; i < 6; ++i) {
            strEnsure += mapTable[(int) (mapTable.length * Math.random())];
            // 直接生成
            String str = strEnsure.substring(i, i + 1);
        }
        return strEnsure;
    }
    //给定范围获得随机颜色
    static Color getRandColor(int fc, int bc) {
        Random random = new Random();
        if (fc > 255) {
            fc = 255;
        }
        if (bc > 255) {
            bc = 255;
        }
        int r = fc + random.nextInt(bc - fc);
        int g = fc + random.nextInt(bc - fc);
        int b = fc + random.nextInt(bc - fc);
        return new Color(r, g, b);
    }
}