码迷,mamicode.com
首页 > 编程语言 > 详细

java实现网页验证码

时间:2017-10-10 16:50:15      阅读:151      评论:0      收藏:0      [点我收藏+]

标签:fun   title   set   next   graphics   ini   template   image   val   

Servlet:

package cn.bdqn.servlet;

import javax.imageio.ImageIO;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.awt.*;
import java.awt.font.ImageGraphicAttribute;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.Random;


@WebServlet(name = "Servlet",urlPatterns = "/yanCode")
public class Servlet extends HttpServlet {
    public void doPost(javax.servlet.http.HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        this.doGet(request,response);

    }

    public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

        String s="abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
        Random random = new Random();
        int width=500;
        int height=50;
        BufferedImage image = new BufferedImage(width,height,BufferedImage.TYPE_INT_RGB);
        Graphics graphics = image.getGraphics();//相当于画笔
        //画背景
        graphics.setColor(Color.gray);
        graphics.fillRect(0,0,width,height);
        graphics.setColor(Color.black);
        for (int i = 0; i <4 ; i++) {
            int index = random.nextInt(s.length());
            String c = s.substring(index, index + 1);
            graphics.drawString(c,width/5*(i+1),15);
        }

        ImageIO.write(image,"jpg",response.getOutputStream());


    }
}

  jsp:

<%--
  Created by IntelliJ IDEA.
  User: Administrator
  Date: 2017/10/10
  Time: 13:04
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
  <head>
    <title>验证码</title>
  </head>
  <body>
  <img src="yanCode" alt="验证码"  style="width: 500px;height:50px">
  <input type="button" value="看不清,更换验证码" id="btn" onclick="changeCode();">

  <script type="text/javascript" src="js/jquery.min.js">
  </script>
  <script type="text/javascript" >
      function changeCode() {
          $("img").attr(‘src‘, ‘yanCode?ts=‘ + new Date().getTime());

      }
  </script>
  </body>
</html>

  

java实现网页验证码

标签:fun   title   set   next   graphics   ini   template   image   val   

原文地址:http://www.cnblogs.com/zqr99/p/7645610.html

(0)
(0)
   
举报
评论 一句话评论(0
登录后才能评论!
© 2014 mamicode.com 版权所有  联系我们:gaon5@hotmail.com
迷上了代码!