圖形驗證碼（基礎）
阿新 • • 發佈：2019-05-04
.com 探測 src str 登錄 key width req 顏色
一、生成圖形驗證碼
1、根據隨機數生成圖片
2、將隨機數存儲到session中
3、將生成的圖片寫到接口的響應中
基類：
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; privateString code;//隨機數 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; } }
控制層：
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 { //生成圖片 ImageCode imageCode = createImageCode(request); //將隨機數存到session中 sessionStrategy.setAttribute(new ServletWebRequest(request), SESSION_KEY, imageCode); ImageIO.write(imageCode.getImage(), "JPEG", response.getOutputStream()); } private ImageCode createImageCode(HttpServletRequest request) { // 在內存中創建圖象 int width = 85, height = 20; BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB); // 獲取圖形上下文 Graphics g = image.getGraphics(); // 生成隨機類 Random random = new Random(); // 設定背景色 g.setColor(getRandColor(200, 250)); g.fillRect(0, 0, width, height); // 設定字體 g.setFont(new Font("Times New Roman", Font.PLAIN, 18)); // 隨機產生155條幹擾線，使圖象中的認證碼不易被其它程序探測到 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); } // 取隨機產生的認證碼(6位數字) String sRand = ""; for (int i = 0; i < 6; i++) { String rand = String.valueOf(random.nextInt(10)); sRand += rand; // 將認證碼顯示到圖象中 g.setColor(new Color(20 + random.nextInt(110), 20 + random .nextInt(110), 20 + random.nextInt(110))); // 調用函數出來的顏色相同，可能是因為種子太接近，所以只能直接生成 g.drawString(rand, 13 * i + 6, 16); } // 圖象生效 g.dispose(); return new ImageCode(image, sRand, 60); } /* * 給定範圍獲得隨機顏色 */ 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); } }
頁面：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>自定義登錄頁面</title>
</head>
<body>
<h2>自定義登錄頁面</h2>
<form action="/authentication/form" method="POST">
<table>
<tr>
<td>用戶名：</td>
<td><input type="text" name="username"></td>
</tr>
<tr>
<td>密碼：</td>
<td><input type="password" name="password"></td>
</tr>
<tr>
<td>圖形驗證碼：</td>
<td>
<input type="text" name="imagecode">
<img src="/code/image" >
</td>
</tr>
<tr>
<td colspan="2">
<button type="submit">登錄</button>
</td>
</tr>
</table>
</form>
</body>
</html>
效果：
ps：圖形驗證碼的各種參數都可以配置到application.yml中，並且圖形驗證碼生成器可以配置為可配置類，默認實現一種，動態配置覆蓋默認配置
圖形驗證碼（基礎）