一、生成图形验证码
1、根据随机数生成图片
2、将随机数存储到session中
3、将生成的图片写到接口的响应中
基类：
package com.nxz.security.core.validatecode;
import lombok.Data;
import java.awt.image.BufferedImage;
import java.time.LocalDateTime;
@Data
public class ImageCode {
private BufferedImage image;
private String code;//随机数
private LocalDateTime expireTime;
public ImageCode(BufferedImage image, String code, int expireIn) {
this.image = image;
this.code = code;
this.expireTime = LocalDateTime.now().plusSeconds(expireIn);
}
public ImageCode(BufferedImage image, String code, LocalDateTime expireTime) {
this.image = image;
this.code = code;
this.expireTime = expireTime;
}
}
控制层：
package com.nxz.security.core.controller;
import com.nxz.security.core.validatecode.ImageCode;
import org.springframework.social.connect.web.HttpSessionSessionStrategy;
import org.springframework.social.connect.web.SessionStrategy;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.context.request.ServletWebRequest;
import javax.imageio.ImageIO;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.Random;
@RestController
public class ValidateCodeController {
private static final String SESSION_KEY = "SESSION_KEY_IMAGE_CODE";
private SessionStrategy sessionStrategy = new HttpSessionSessionStrategy();
@GetMapping("/code/image")
public void createCode(HttpServletRequest request, HttpServletResponse response) throws IOException {
//生成图片
ImageCode imageCode = createImageCode(request);
//将随机数存到session中
sessionStrategy.setAttribute(new ServletWebRequest(request), SESSION_KEY, imageCode);
ImageIO.write(imageCode.getImage(), "JPEG", response.getOutputStream());
}
private ImageCode createImageCode(HttpServletRequest request) {
// 在内存中创建图象
int width = 85, 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155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 < 155; 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);
}
// 取随机产生的认证码(6位数字)
String sRand = "";
for (int i = 0; i < 6; i++) {
String rand = String.valueOf(random.nextInt(10));
sRand += rand;
// 将认证码显示到图象中
g.setColor(new Color(20 + random.nextInt(110), 20 + random
.nextInt(110), 20 + random.nextInt(110)));
// 调用函数出来的颜色相同，可能是因为种子太接近，所以只能直接生成
g.drawString(rand, 13 * i + 6, 16);
}
// 图象生效
g.dispose();
return new ImageCode(image, sRand, 60);
}
/*
* 给定范围获得随机颜色
*/
private 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);
}
}
页面：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>自定义登录页面</title>
</head>
<body>
<h2>自定义登录页面</h2>
<form action="/authentication/form" method="POST">
<table>
<tr>
<td>用户名：</td>
<td><input type="text" name="username"></td>
</tr>
<tr>
<td>密码：</td>
<td><input type="password" name="password"></td>
</tr>
<tr>
<td>图形验证码：</td>
<td>
<input type="text" name="imagecode">
<img src="/code/image" >
</td>
</tr>
<tr>
<td colspan="2">
<button type="submit">登录</button>
</td>
</tr>
</table>
</form>
</body>
</html>
效果：
ps：图形验证码的各种参数都可以配置到application.yml中，并且图形验证码生成器可以配置为可配置类，默认实现一种，动态配置覆盖默认配置
原文地址：https://www.cnblogs.com/nxzblogs/p/10808386.html
时间： 2024-11-02 08:11:18