栏目分类:
子分类:
返回
名师互学网用户登录
快速导航关闭
当前搜索
当前分类
子分类
实用工具
热门搜索
名师互学网 > IT > 软件开发 > 后端开发 > Java

java登录验证码实现代码

Java 更新时间: 发布时间: IT归档 最新发布 模块sitemap 名妆网 法律咨询 聚返吧 英语巴士网 伯小乐 网商动力

java登录验证码实现代码

VerifyCodeServlet.java类:
复制代码 代码如下:
package com.spring.controller;
import java.awt.Color;        
import java.awt.Font;        
import java.awt.Graphics2D;        
import java.awt.image.BufferedImage;        
import java.util.Random;        
import javax.imageio.ImageIO;        
import javax.servlet.ServletException;        
import javax.servlet.ServletOutputStream;        
import javax.servlet.http.HttpServlet;        
import javax.servlet.http.HttpServletRequest;        
import javax.servlet.http.HttpServletResponse;        
import javax.servlet.http.HttpSession; 
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
@Controller
public class VerifyCodeServlet extends HttpServlet {
  // 验证码图片的宽度。        
    private int width = 60;        
    // 验证码图片的高度。        
    private int height = 20;        
    // 验证码字符个数        
    private int codeCount = 4;        
    private int x = 0;        
    // 字体高度        
    private int fontHeight;        
    private int codeY;        
    char[] codeSequence = { 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J',        
            'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W',        
            'X', 'Y', 'Z', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9' };        
           
    public void initxuan() throws ServletException {        
        // 从web.xml中获取初始信息        
        // 宽度        
        String strWidth ="80";        
        // 高度        
        String strHeight ="30";        
        // 字符个数        
        String strCodeCount = "4";        
        // 将配置的信息转换成数值        
        try {        
            if (strWidth != null && strWidth.length() != 0) {        
                width = Integer.parseInt(strWidth);        
            }        
            if (strHeight != null && strHeight.length() != 0) {        
                height = Integer.parseInt(strHeight);        
            }        
            if (strCodeCount != null && strCodeCount.length() != 0) {        
                codeCount = Integer.parseInt(strCodeCount);        
            }        
        } catch (NumberFormatException e) {        
        }        
        x = width / (codeCount + 1);        
        fontHeight = height - 2;        
        codeY = height - 4;        
    }  
    @RequestMapping(value="xuan/verifyCode",method=RequestMethod.GET)
    public void service(HttpServletRequest req, HttpServletResponse resp)        
            throws ServletException, java.io.IOException {
        initxuan();
        // 定义图像buffer        
        BufferedImage buffImg = new BufferedImage(width, height,        
                BufferedImage.TYPE_INT_RGB);        
        Graphics2D g = buffImg.createGraphics();        
        // 创建一个随机数生成器类        
        Random random = new Random();        
        // 将图像填充为白色        
        g.setColor(Color.WHITE);        
        g.fillRect(0, 0, width, height);        
        // 创建字体,字体的大小应该根据图片的高度来定。        
        Font font = new Font("Fixedsys", Font.PLAIN, fontHeight);        
        // 设置字体。        
        g.setFont(font);        
        // 画边框。        
        g.setColor(Color.BLACK);        
        g.drawRect(0, 0, width - 1, height - 1);        
        // 随机产生160条干扰线,使图象中的认证码不易被其它程序探测到。        
        g.setColor(Color.BLACK);        
        for (int i = 0; i < 10; 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);        
        }        
        // randomCode用于保存随机产生的验证码,以便用户登录后进行验证。        
        StringBuffer randomCode = new StringBuffer();        
        int red = 0, green = 0, blue = 0;        
        // 随机产生codeCount数字的验证码。        
        for (int i = 0; i < codeCount; i++) {        
            // 得到随机产生的验证码数字。        
            String strRand = String.valueOf(codeSequence[random.nextInt(36)]);        
            // 产生随机的颜色分量来构造颜色值,这样输出的每位数字的颜色值都将不同。        
            red = random.nextInt(255);        
            green = random.nextInt(255);        
            blue = random.nextInt(255);        
            // 用随机产生的颜色将验证码绘制到图像中。        
            g.setColor(new Color(red, green, blue));        
            g.drawString(strRand, (i + 1) * x, codeY);        
            // 将产生的四个随机数组合在一起。        
            randomCode.append(strRand);        
        }        
        // 将四位数字的验证码保存到Session中。        
        HttpSession session = req.getSession();        
        session.setAttribute("validateCode", randomCode.toString());        
        // 禁止图像缓存。        
        resp.setHeader("Pragma", "no-cache");        
        resp.setHeader("Cache-Control", "no-cache");        
        resp.setDateHeader("Expires", 0);        
        resp.setContentType("image/jpeg");        
        // 将图像输出到Servlet输出流中。        
        ServletOutputStream sos = resp.getOutputStream();        
        ImageIO.write(buffImg, "jpeg", sos);        
        sos.close();        
    }        
}

ResultServlet.java:
复制代码 代码如下:
package com.spring.controller;
import java.io.IOException;        
import java.io.PrintWriter;        
import javax.servlet.ServletException;               
import javax.servlet.http.HttpServletRequest;        
import javax.servlet.http.HttpServletResponse;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
@Controller
public class ResultServlet {
     @RequestMapping(value="resultServlet/validateCode",method=RequestMethod.POST)
     public void doPost(HttpServletRequest request, HttpServletResponse response)        
             throws ServletException, IOException {        
         response.setContentType("text/html;charset=utf-8");        
         String validateC = (String) request.getSession().getAttribute("validateCode");        
         String veryCode = request.getParameter("c");        
         PrintWriter out = response.getWriter();        
         if(veryCode==null||"".equals(veryCode)){        
             out.println("验证码为空");        
         }else{        
             if(validateC.equals(veryCode)){        
                 out.println("验证码正确");        
             }else{        
                 out.println("验证码错误");        
             }        
         }        
         out.flush();        
         out.close();        
     }        
}

jsp页面:
复制代码 代码如下:
<%@ page language="java" contentType="text/html; charset=UTF-8"      
    pageEncoding="UTF-8"%>      
      
      
          
       
        test verify code 
     
          
              
              
        换一张      
              
              
          

 

运行效果:
转载请注明:文章转载自 www.mshxw.com
本文地址:https://www.mshxw.com/it/152924.html
我们一直用心在做
关于我们 文章归档 网站地图 联系我们

版权所有 (c)2021-2022 MSHXW.COM

ICP备案号:晋ICP备2021003244-6号