1 package com.donleo.ssm.common;
2
3
4 import com.donleo.ssm.utils.CommonPath;
5 import redis.clients.jedis.Jedis;
6
7 import javax.imageio.ImageIO;
8 import javax.servlet.ServletException;
9 import javax.servlet.annotation.WebServlet;
10 import javax.servlet.http.HttpServlet;
11 import javax.servlet.http.HttpServletRequest;
12 import javax.servlet.http.HttpServletResponse;
13 import java.awt.*;
14 import java.awt.image.BufferedImage;
15 import java.io.IOException;
16 import java.io.OutputStream;
17 import java.util.Random;
18
19 /**
20 * @author liangd
21 * date 2020-10-16 11:31
22 * code 生成验证码图片
23 */
24 @WebServlet("/code")
25 public class CodeServlet extends HttpServlet {
26 @Override
27 protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
28 //创建空白图片
29 BufferedImage image = new BufferedImage(90, 30, BufferedImage.TYPE_INT_RGB);
30 //1.获取图片画笔
31 Graphics g = image.getGraphics();
32 Random r = new Random();//随机数
33 // r.nextInt(255)，随机数在0到255之间 而且必须是整数
34 //2.设置画笔颜色
35 // 设置背景颜色，RGB 三个参数
36 g.setColor(new Color(r.nextInt(255), r.nextInt(255), r.nextInt(255)));
37 //3. .绘制矩形的背景
38 g.fillRect(0, 0, 90, 30);
39
40
41 //4.调用自定义的方法,获取长度为5的字母数字组合的字符串
42 String number = getNumber(5);
43 // System.out.println(number);
44 req.getSession().setAttribute("code", number);
45 Jedis jedis = new Jedis();
46 jedis.auth(CommonPath.REDIS_AUTH.getValue());
47 jedis.set("backCode",number);
48 g.setColor(new Color(0, 0, 0));
49 g.setFont(new Font("宋体", Font.BOLD, 24));
50 //5.设置颜色字体后，绘制字符串
51 g.drawString(number, 5, 25);
52 //6.绘制8条干扰线
53 for (int i = 0; i < 18; i++) {
54 g.setColor(new
55 Color(r.nextInt(255), r.nextInt(255), r.nextInt(255), r.nextInt(255)));
56 g.drawLine(r.nextInt(90),
57 r.nextInt(30),
58 r.nextInt(90),
59 r.nextInt(30));
60 // 直线参数 （a,b,x,y),a,b代表起点，x，y代表终点
61 }
62 resp.setContentType("image/ jpeg");
63 OutputStream ops = resp.getOutputStream();
64 ImageIO.write(image, "jpeg", ops);
65 ops.close();
66
67 }
68
69 /**
70 * 字符串的拼接
71 *
72 * @param size
73 * @return
74 */
75 private String getNumber(int size) {
76 //把I和O都去掉，因为和1,0不好识别
77 String str = "ASDFGHJKLQWERTYUIOPZXCVBNM";
78 StringBuilder number = new StringBuilder();
79 Random r = new Random();
80 for (int i = 0; i < size; i++) {
81 number.append(str.charAt(r.nextInt(str.length())));
82 // str.charAt 拿到下标为0-str长度之间的下标，下标从0开始
83 }
84 return number.toString();
85 }
86 }
