Java生成随机验证码
编程技术 / houtizong 发布于 3年前 79
package com.tg.snail.core.util;import java.awt.Color;import java.awt.Font;import java.awt.Graphics;import java.awt.image.BufferedImage;import java.io.IOException;import java.util.Random;import javax.imageio.ImageIO;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import javax.servlet.http.HttpSession;import org.apache.log4j.Logger;import org.springframework.util.StringUtils;/** * 验证码生成工具类 * @author penghy * @date 2014-02-27 */public abstract class RandomCodeUtils {private static Logger logger = Logger.getLogger(RandomCodeUtils.class);private static final String RANDOM_CODE_KEY = "random"; //验证码放在session中的keyprivate static final int CODE_NUM = 4; //验证码字符个数// 设置图形验证码中字符串的字体和大小 private static Font myFont = new Font("Arial", Font.BOLD, 16); //随机字符数组private static char[] charSequence = "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789".toCharArray(); private static Random random = new Random();/** * 生成随机验证码 * @param request * @param response */public static void createRandomCode(HttpServletRequest request, HttpServletResponse response){// 阻止生成的页面内容被缓存，保证每次重新生成随机验证码 response.setHeader("Pragma", "No-cache"); response.setHeader("Cache-Control", "no-cache"); response.setDateHeader("Expires", 0); response.setContentType("image/jpeg"); // 指定图形验证码图片的大小 int width = 80, height = 25; // 生成一张新图片 BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB); // 在图片中绘制内容 Graphics g = image.getGraphics(); g.setColor(getRandomColor(200, 250)); g.fillRect(1, 1, width - 1, height - 1); g.setColor(new Color(102, 102, 102)); g.drawRect(0, 0, width - 1, height - 1); g.setFont(myFont); // 随机生成线条，让图片看起来更加杂乱 g.setColor(getRandomColor(160, 200)); for (int i = 0; i < 155; i++) { int x = random.nextInt(width - 1);// 起点的x坐标 int y = random.nextInt(height - 1);// 起点的y坐标 int x1 = random.nextInt(6) + 1;// x轴偏移量 int y1 = random.nextInt(12) + 1;// y轴偏移量 g.drawLine(x, y, x + x1, y + y1); } // 随机生成线条，让图片看起来更加杂乱 for (int i = 0; i < 70; i++) { int x = random.nextInt(width - 1); int y = random.nextInt(height - 1); int x1 = random.nextInt(12) + 1; int y1 = random.nextInt(6) + 1; g.drawLine(x, y, x - x1, y - y1); } // 该变量用来保存系统生成的随机字符串 StringBuilder sRand = new StringBuilder(CODE_NUM); for (int i = 0; i < CODE_NUM; i++) { // 取得一个随机字符 String tmp = getRandomChar(); sRand.append(tmp); // 将系统生成的随机字符添加到图形验证码图片上 g.setColor(new Color(20 + random.nextInt(110), 20 + random.nextInt(110), 20 + random.nextInt(110))); g.drawString(tmp, 15 * i + 10, 20); } // 取得用户Session HttpSession session = request.getSession(true); // 将系统生成的图形验证码添加 session.setAttribute(RANDOM_CODE_KEY, sRand.toString()); g.dispose(); // 输出图形验证码图片 try {ImageIO.write(image, "JPEG", response.getOutputStream());} catch (IOException e) {e.printStackTrace();} }/** * 检查用户输入的验证码是否正确 * @param request * @param inputCode * @return true: 正确, false:不正确 */public static boolean checkRandomCode(HttpServletRequest request, String inputCode){HttpSession session = request.getSession(false);if(session != null && StringUtils.hasLength(inputCode)){String code = (String) session.getAttribute(RANDOM_CODE_KEY);logger.info("inputCode:"+inputCode.trim()+",code:"+code);return inputCode.trim().equalsIgnoreCase(code);}return false;}/** * 移除验证码 * @param request * @param inputCode */public static void removeRandomCode(HttpServletRequest request){HttpSession session = request.getSession(false);if(session != null){ session.removeAttribute(RANDOM_CODE_KEY);}} // 生成随机颜色 private static Color getRandomColor(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); } // 随机生成一个字符 private static String getRandomChar() { int index = random.nextInt(charSequence.length); return String.valueOf(charSequence[index]); }}
上一篇：maven工程依赖包导出
请勿发布不友善或者负能量的内容。与人为善，比聪明更重要！
技术博客集 - 网站简介：
前后端技术：
后端基于Hyperf2.1框架开发,前端使用Bootstrap可视化布局系统生成
网站主要作用：
1.编程技术分享及讨论交流，内置聊天系统;
2.测试交流框架问题，比如：Hyperf、Laravel、TP、beego;
3.本站数据是基于大数据采集等爬虫技术为基础助力分享知识，如有侵权请发邮件到站长邮箱，站长会尽快处理;
4.站长邮箱：[email protected];
文章归档
文章标签
友情链接
