java生成验证码

it2022-05-05 166

1.首先写工具类

import java.awt.*; import java.awt.image.BufferedImage; public class VCodeUtil { private static final int WIDTH = 70;//验证码长度 private static final int HEIGHT = 20;//验证码高度 private static final int LENGTH = 4;//验证码位数 /** * 获取验证码 * */ public static BufferedImage getVCodeImage(char[] rands){ // 创建内存图象并获得其图形上下文 BufferedImage image = new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_RGB); Graphics g = image.getGraphics(); drawBackground(g); drawRands(g, rands); // 结束图像的绘制过程，完成图像 g.dispose(); return image; } /** * 生产随机码 * */ public static char[] generateVCode() { // 定义验证码的字符表 String chars = "23456789ABCDEFGHJKLMNPQRSTUVWXYZ"; char[] rands = new char[LENGTH]; for (int i = 0; i < LENGTH; i++) { int rand = (int) (Math.random() * chars.length()); rands[i] = chars.charAt(rand); } return rands; } /** * 画出验证码 * */ private static Graphics drawRands(Graphics g, char[] rands) { g.setColor(Color.BLACK); g.setFont(new Font(null, Font.ITALIC | Font.BOLD, 18)); // 在不同的高度上输出验证码的每个字符 g.drawString("" + rands[0], 1, 17); g.drawString("" + rands[1], 16, 15); g.drawString("" + rands[2], 31, 18); g.drawString("" + rands[3], 46, 16); return g; } /** * 画背景 * */ private static Graphics drawBackground(Graphics g) { g.setColor(new Color(0xDCDCDC)); g.fillRect(0, 0, WIDTH, HEIGHT); // 随机产生120个干扰点 for (int i = 0; i < 120; i++) { int x = (int) (Math.random() * WIDTH); int y = (int) (Math.random() * HEIGHT); int red = (int) (Math.random() * 255); int green = (int) (Math.random() * 255); int blue = (int) (Math.random() * 255); g.setColor(new Color(red, green, blue)); g.drawOval(x, y, 1, 0); } // 加两条干扰线 g.drawLine(0, 5, 90, 5); g.drawLine(0, 15, 90, 15); return g; } }

2.写一个验证码服务接口

/** * 验证码服务 * Created by gameloft9 on 2017/12/6. */ public interface VCodeService { /** * 输出验证码到客户端 * */ void outPutVCode(HttpServletRequest request, HttpServletResponse response) throws Exception; }

3.验证码实现类

import java.awt.image.BufferedImage; import java.io.ByteArrayOutputStream; import javax.imageio.ImageIO; import javax.servlet.ServletOutputStream; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import javax.servlet.http.HttpSession; import org.springframework.stereotype.Service; import com.utils.VCodeUtil; /** * 验证码服务 * */ @Service public class VCodeServiceImpl implements VCodeService{ /** * 输出验证码 * */ public void outPutVCode(HttpServletRequest request, HttpServletResponse response) throws Exception{ HttpSession session = request.getSession(); response.setContentType("image/jpeg"); ServletOutputStream sos = response.getOutputStream(); // 设置浏览器不要缓存此图片 response.setHeader("Pragma", "No-cache"); response.setHeader("Cache-Control", "no-cache"); response.setDateHeader("Expires", 0); //创建内存图象 char[] vCode = VCodeUtil.generateVCode(); BufferedImage image = VCodeUtil.getVCodeImage(vCode); // 将图像输出到客户端 ByteArrayOutputStream bos = new ByteArrayOutputStream(); ImageIO.write(image, "JPEG", bos); byte[] buf = bos.toByteArray(); response.setContentLength(buf.length); // 下面的语句也可写成：bos.writeTo(sos); sos.write(buf); bos.close(); sos.close(); // 将当前验证码存入到Session中 session.setAttribute("vcode", new String(vCode)); } }

4.书写controller类

import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestMethod; import com.cwh.springbootMybatis.service.system.VCodeService; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; /** * 图片验证码控制器 * */ @Controller public class VCodeController { @Autowired VCodeService vCodeServiceImpl; static { //防止二维码显示不了 System.setProperty("java.awt.headless","true"); } /** * 获取验证码 * @param response */ @RequestMapping(value="/getVCode",method= RequestMethod.GET) public void getGifCode(HttpServletResponse response, HttpServletRequest request) throws Exception{ vCodeServiceImpl.outPutVCode(request,response); } }

5.登录页面部分代码

6.更换验证码代码

/** * 更换验证码 * */ $('.code img').click(function () { this.src = $tool.getContext() + 'getVCode'; });

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