生成图片验证码工具类

import org.apache.commons.codec.binary.Base64;

import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.Random;

/**
 * Created by IntelliJ IDEA
 * 这是一个神奇的Class
 *
 * @author zhz
 * @date 2020/3/26 13:45
 */
public class CheckPicCodeUtil {

    private static String picCode;

    public CheckPicCodeUtil() {
    }

    public static String getPicCode() {
        return picCode;
    }

    public static void setPicCode(String picCode) {
        CheckPicCodeUtil.picCode = picCode;
    }

    public static String getCheckCode(){
        //验证码中的字符由数字和大小写字母组成
        String code = "0123456789qwertyuiopasdfghjklzxcvbnmQWERTYUIOPASDFGHJKLZXCVBNM";
        Random r = new Random();
        StringBuffer sb = new StringBuffer();
        for (int i = 0; i < 4; i++) {
            sb.append(code.charAt(r.nextInt(code.length())));
        }

        return sb.toString();
    }

    public static BufferedImage showPic() throws IOException {
        String code=getCheckCode();
        setPicCode(code);
        int width=80;
        int height=30;
        BufferedImage image=new BufferedImage(width,height,BufferedImage.TYPE_INT_RGB);
        Graphics g=image.getGraphics();
        g.setColor(Color.white);
        g.fillRect(0,0,width,height);
        Random r=new Random();
        for (int i=0;i<3;i++){
            g.setColor(new Color(r.nextInt(255),r.nextInt(255),r.nextInt(255)));
            g.drawLine(r.nextInt(80),r.nextInt(30),r.nextInt(80),r.nextInt(80));
        }
        g.setColor(new Color(r.nextInt(255),r.nextInt(255),r.nextInt(255)));
        g.setFont(new Font("黑体",Font.BOLD,24));
        g.drawString(code,15,20);
        g.dispose();//图像生效
        return image;
    }
    public static String encodeBase64ImgCode() throws IOException{
        BufferedImage codeImg=showPic();
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        ImageIO.write(codeImg, "JPEG", out);
        byte[] b = out.toByteArray();
        String imgString = Base64.encodeBase64String(b);
        return "data:image/JPEG;base64," + imgString;
    }

    public static void main(String[] args) throws IOException {
        String base64PicCodeImage = encodeBase64ImgCode();
        String checkCode = getPicCode();
        System.out.println("验证码==》"+checkCode);
        System.out.println("base64图片字符串==》"+base64PicCodeImage);
    }


}

验证结果:

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<img src="data:image/JPEG;base64,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
">
</body>
</html>

参考:https://blog.csdn.net/Solder_Sun/article/details/81363117

原文地址:https://www.cnblogs.com/wdzhz/p/12574015.html