java(Spring boot)实现获取验证码图片-蒲公英云

文章目录

- 一、工具类代码
- 二、工具类调用
- - 1、获取验证码接口
  - 2、获取验证码接口用于登录验证

一、工具类代码

创建CreateVerifiCodeImage类，将下面代码复制到该类中：

import java.awt.*;
import java.awt.image.BufferedImage;
import java.util.Random;
/**
 * @project: ssm_sms
 * @description: 绘制验证码图片
 */
public class CreateVerifiCodeImage {
    private static int WIDTH = 90;
    private static int HEIGHT = 35;
    private static int FONT_SIZE = 20; //字符大小
    private static char[] verifiCode; //验证码
    private static BufferedImage verifiCodeImage; //验证码图片
    /**
     * @description: 获取验证码图片
     * @param: no
     * @return: java.awt.image.BufferedImage
     */
    public static BufferedImage getVerifiCodeImage() {
        verifiCodeImage = new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_BGR);// create a image
        Graphics graphics = verifiCodeImage.getGraphics();
        verifiCode = generateCheckCode();
        drawBackground(graphics);
        drawRands(graphics, verifiCode);
        graphics.dispose();
        return verifiCodeImage;
    }
    /**
     * @description: 获取验证码
     * @param: no
     * @return: char[]
     */
    public static char[] getVerifiCode() {
        return verifiCode;
    }
    /**
     * @description: 随机生成验证码
     * @param: no
     * @return: char[]
     */
    private static char[] generateCheckCode() {
        String chars = "0123456789abcdefghijklmnopqrstuvwxyz" + "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
        char[] rands = new char[4];
        for (int i = 0; i < 4; i++) {
            int rand = (int) (Math.random() * (10 + 26 * 2));
            rands[i] = chars.charAt(rand);
        }
        return rands;
    }
    /**
     * @description: 绘制验证码
     * @param: g
     * @param: rands
     * @return: void
     */
    private static void drawRands(Graphics g, char[] rands) {
        g.setFont(new Font("Console", Font.BOLD, FONT_SIZE));
        for (int i = 0; i < rands.length; i++) {
            g.setColor(getRandomColor());
            g.drawString("" + rands[i], i * FONT_SIZE + 10, 25);
        }
    }
    /**
     * @description: 绘制验证码图片背景
     * @param: g
     * @return: void
     */
    private static void drawBackground(Graphics g) {
        g.setColor(Color.white);
        g.fillRect(0, 0, WIDTH, HEIGHT);
        // 绘制验证码干扰点
        for (int i = 0; i < 200; i++) {
            int x = (int) (Math.random() * WIDTH);
            int y = (int) (Math.random() * HEIGHT);
            g.setColor(getRandomColor());
            g.drawOval(x, y, 1, 1);
        }
    }
    /**
     * @description: 获取随机颜色
     * @param: no
     * @return: java.awt.Color
     */
    private static Color getRandomColor() {
        Random ran = new Random();
        return new Color(ran.nextInt(220), ran.nextInt(220), ran.nextInt(220));
    }
}

二、工具类调用

1、获取验证码接口

通过调用工具类getVerifiCodeImage 即可获取到验证码图片

@GetMapping("/getVerifiCodeImage")
    public void getVerifiCodeImage(HttpServletRequest request, HttpServletResponse response){
        // 获取图片
        BufferedImage verifiCodeImage = CreateVerifiCodeImage.getVerifiCodeImage();
        // 将验证码图片响应给浏览器
        try {
            ImageIO.write(verifiCodeImage,"JPEG",response.getOutputStream());
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

运行项目，打开浏览器访问该接口地址，页面就会显示生成的验证码图片，刷新验证码，获取的验证码也会随之更新：
在这里插入图片描述

2、获取验证码接口用于登录验证

获取验证码显示在前端后，但验证码功能如登录功能一般还要验证输入的验证码是否正确，即在获取验证码图片的同时，还需获取验证码图片上的值，并将其存储到HttpServletRequest的session域中，用于登录验证。

@GetMapping("/getVerifiCodeImage")
    public void getVerifiCodeImage(HttpServletRequest request, HttpServletResponse response){
        // 获取图片
        BufferedImage verifiCodeImage = CreateVerifiCodeImage.getVerifiCodeImage();
        // 获取图片上的验证码
        String verifiCode =new String( CreateVerifiCodeImage.getVerifiCode());
        // 将验证码文本放入session域,为下一次验证做准备
        HttpSession session = request.getSession();
        session.setAttribute("verifiCode",verifiCode);
        // 将验证码图片响应给浏览器
        try {
            ImageIO.write(verifiCodeImage,"JPEG",response.getOutputStream());
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

在登录接口从HttpServletRequest中获取session里存储的验证码值，并与用户输入的验证码进行校验，校验用户输入的验证码正确即再验证登录的账号即密码是否正确：

@PostMapping("/login")
    public Result login(@RequestBody LoginForm loginForm, HttpServletRequest request){
        // 验证码校验
        HttpSession session = request.getSession();
        String sessionVerifiCode = (String)session.getAttribute("verifiCode");
        String loginVerifiCode = loginForm.getVerifiCode();
        if("".equals(sessionVerifiCode) || null == sessionVerifiCode){
            return Result.fail().message("验证码失效,请刷新后重试");
        }
        if (!sessionVerifiCode.equalsIgnoreCase(loginVerifiCode)){
            return Result.fail().message("验证码输入错误，请重新输入！");
        }
        // 从session域中移除现有验证码
        session.removeAttribute("verifiCode");
        // 以下可继续进行登录的账号密码等验证逻辑
    }