java验证码

package com.jhinno.appportal.verifyCode;

import java.awt.*;
import java.awt.image.BufferedImage;
import java.util.Random;

/**
 * @Author: zewang
 * @Date: 2021/12/17/0017 10:45
 */
public class VerifyCode {

    public static String drawRandomText(int width, int height, BufferedImage verifyImg) {
        Graphics2D graphics = (Graphics2D) verifyImg.getGraphics();
        //设置画笔颜色-验证码背景色
        graphics.setColor(Color.WHITE);
        //填充背景
        graphics.fillRect(0, 0, width, height);
        graphics.setFont(new Font("微软雅黑", Font.BOLD, 22));
        //数字和字母的组合
        String baseNumLetter = "123456789abcdefghijklmnopqrstuvwxyzABCDEFGHJKLMNPQRSTUVWXYZ";
        StringBuffer sBuffer = new StringBuffer();
        //旋转原点的 x 坐标
        int x = 10;
        String ch = "";
        Random random = new Random();
        for (int i = 0; i < 4; i++) {
            graphics.setColor(getRandomColor());
            //设置字体旋转角度
            //角度小于20度
            int degree = random.nextInt() % 20;
            int dot = random.nextInt(baseNumLetter.length());
            ch = baseNumLetter.charAt(dot) + "";
            sBuffer.append(ch);
            //正向旋转
            graphics.rotate(degree * Math.PI / 180, x, 25);
            graphics.drawString(ch, x, 25);
            //反向旋转
            graphics.rotate(-degree * Math.PI / 180, x, 25);
            x += 20;
        }
        //画干扰线
        for (int i = 0; i < 4; i++) {
            // 设置随机颜色
            graphics.setColor(getRandomColor());
            // 随机画线
            graphics.drawLine(random.nextInt(width), random.nextInt(height),
                    random.nextInt(width), random.nextInt(height));
        }
        //添加噪点
        for (int i = 0; i < 20; i++) {
            int x1 = random.nextInt(width);
            int y1 = random.nextInt(height);
            graphics.setColor(getRandomColor());
            graphics.fillRect(x1, y1, 2, 2);
        }
        return sBuffer.toString();
    }

    /**
     * 随机取色
     */
    private static Color getRandomColor() {
        Random ran = new Random();
        Color color = new Color(ran.nextInt(256),
                ran.nextInt(256), ran.nextInt(256));
        return color;

    }
}

try {
    HashMap<String, String> hashMap = new HashMap<>();
    //生成对应宽高的初始图片
    int width = 90;
    int height = 40;
    BufferedImage verifyImg = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
    //单独的一个类方法，出于代码复用考虑，进行了封装。
    //功能是生成验证码字符并加上噪点，干扰线，返回值为验证码字符
    String randomText = VerifyCode.drawRandomText(width, height, verifyImg);
    //获取输出流读取照片
    ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
    //输出图片流
    ImageIO.write(verifyImg, "png", outputStream);
    //将图片转为base64字符串给前端页面做展示
    BASE64Encoder encoder = new BASE64Encoder();
    String base64 = encoder.encodeBuffer(outputStream.toByteArray()).trim();
    base64 = base64.replaceAll("\n", "").replaceAll("\r", "");
    //图片的base64编码
    hashMap.put("code", "data:image/jpg;base64," + base64);
    //将后台生成的校验码值存入redis
    String verifyCodeId = "yzm"+randomText + "_" +  UUID.randomUUID().toString();
    Jedis jedis = RedisClient.getInstance().getConnection();
    //传回前端
    //验证码
    hashMap.put("verifyCode", randomText);
    //验证码id
    hashMap.put("verifyCodeId", verifyCodeId);
    logger.info("verifyCode:" + randomText + ";verifyCodeId:" + verifyCodeId);
    result.setData(hashMap);
    result.success();
} catch (Exception e) {
    logger.error(e);
    result.failed();
}