jsp验证码

GetCaptcha.java

package servlet;import java.io.IOException;    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 java.util.*;    import java.awt.*;    import java.awt.image.*;    import javax.imageio.*;    /**  *   * @author mzba  *  */  public class GetCaptcha extends HttpServlet {        private static final long serialVersionUID = 1L;            /**       * @see HttpServlet#HttpServlet()       */        public GetCaptcha() {            super();            // TODO Auto-generated constructor stub        }        /**       * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse       *      response)       */        protected void doGet(HttpServletRequest request,                HttpServletResponse response) throws ServletException, IOException {        //设置页面不缓存 //    hanzi(request, response) ;    shuzi_zimu(request, response);    }            Color getRandColor(int fc, int bc) {// 给定范围获得随机颜色            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);        }        Color getRandColor(Random random, int fc, int bc) {        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);    }    /**     * 生成汉字     * @param request     * @param response     * @throws IOException     */    public void hanzi(HttpServletRequest request, HttpServletResponse response) throws IOException{    response.setHeader("Pragma","No-cache");     response.setHeader("Cache-Control","no-cache");     response.setDateHeader("Expires", 0);    // 设置图片的长宽     int width=176, height=30;     //设置备选汉字，剔除一些不雅的汉字     String base = "\u7684\u4e00\u4e86\u662f\u6211\u4e0d\u5728\u4eba\u4eec\u6709\u6765\u4ed6\u8fd9\u4e0a\u7740\u4e2a\u5730\u5230\u5927\u91cc\u8bf4\u5c31\u53bb\u5b50\u5f97\u4e5f\u548c\u90a3\u8981\u4e0b\u770b\u5929\u65f6\u8fc7\u51fa\u5c0f\u4e48\u8d77\u4f60\u90fd\u628a\u597d\u8fd8\u591a\u6ca1\u4e3a\u53c8\u53ef\u5bb6\u5b66\u53ea\u4ee5\u4e3b\u4f1a\u6837\u5e74\u60f3\u751f\u540c\u8001\u4e2d\u5341\u4ece\u81ea\u9762\u524d\u5934\u9053\u5b83\u540e\u7136\u8d70\u5f88\u50cf\u89c1\u4e24\u7528\u5979\u56fd\u52a8\u8fdb\u6210\u56de\u4ec0\u8fb9\u4f5c\u5bf9\u5f00\u800c\u5df1\u4e9b\u73b0\u5c71\u6c11\u5019\u7ecf\u53d1\u5de5\u5411\u4e8b\u547d\u7ed9\u957f\u6c34\u51e0\u4e49\u4e09\u58f0\u4e8e\u9ad8\u624b\u77e5\u7406\u773c\u5fd7\u70b9\u5fc3\u6218\u4e8c\u95ee\u4f46\u8eab\u65b9\u5b9e\u5403\u505a\u53eb\u5f53\u4f4f\u542c\u9769\u6253\u5462\u771f\u5168\u624d\u56db\u5df2\u6240\u654c\u4e4b\u6700\u5149\u4ea7\u60c5\u8def\u5206\u603b\u6761\u767d\u8bdd\u4e1c\u5e2d\u6b21\u4eb2\u5982\u88ab\u82b1\u53e3\u653e\u513f\u5e38\u6c14\u4e94\u7b2c\u4f7f\u5199\u519b\u5427\u6587\u8fd0\u518d\u679c\u600e\u5b9a\u8bb8\u5feb\u660e\u884c\u56e0\u522b\u98de\u5916\u6811\u7269\u6d3b\u90e8\u95e8\u65e0\u5f80\u8239\u671b\u65b0\u5e26\u961f\u5148\u529b\u5b8c\u5374\u7ad9\u4ee3\u5458\u673a\u66f4\u4e5d\u60a8\u6bcf\u98ce\u7ea7\u8ddf\u7b11\u554a\u5b69\u4e07\u5c11\u76f4\u610f\u591c\u6bd4\u9636\u8fde\u8f66\u91cd\u4fbf\u6597\u9a6c\u54ea\u5316\u592a\u6307\u53d8\u793e\u4f3c\u58eb\u8005\u5e72\u77f3\u6ee1\u65e5\u51b3\u767e\u539f\u62ff\u7fa4\u7a76\u5404\u516d\u672c\u601d\u89e3\u7acb\u6cb3\u6751\u516b\u96be\u65e9\u8bba\u5417\u6839\u5171\u8ba9\u76f8\u7814\u4eca\u5176\u4e66\u5750\u63a5\u5e94\u5173\u4fe1\u89c9\u6b65\u53cd\u5904\u8bb0\u5c06\u5343\u627e\u4e89\u9886\u6216\u5e08\u7ed3\u5757\u8dd1\u8c01\u8349\u8d8a\u5b57\u52a0\u811a\u7d27\u7231\u7b49\u4e60\u9635\u6015\u6708\u9752\u534a\u706b\u6cd5\u9898\u5efa\u8d76\u4f4d\u5531\u6d77\u4e03\u5973\u4efb\u4ef6\u611f\u51c6\u5f20\u56e2\u5c4b\u79bb\u8272\u8138\u7247\u79d1\u5012\u775b\u5229\u4e16\u521a\u4e14\u7531\u9001\u5207\u661f\u5bfc\u665a\u8868\u591f\u6574\u8ba4\u54cd\u96ea\u6d41\u672a\u573a\u8be5\u5e76\u5e95\u6df1\u523b\u5e73\u4f1f\u5fd9\u63d0\u786e\u8fd1\u4eae\u8f7b\u8bb2\u519c\u53e4\u9ed1\u544a\u754c\u62c9\u540d\u5440\u571f\u6e05\u9633\u7167\u529e\u53f2\u6539\u5386\u8f6c\u753b\u9020\u5634\u6b64\u6cbb\u5317\u5fc5\u670d\u96e8\u7a7f\u5185\u8bc6\u9a8c\u4f20\u4e1a\u83dc\u722c\u7761\u5174\u5f62\u91cf\u54b1\u89c2\u82e6\u4f53\u4f17\u901a\u51b2\u5408\u7834\u53cb\u5ea6\u672f\u996d\u516c\u65c1\u623f\u6781\u5357\u67aa\u8bfb\u6c99\u5c81\u7ebf\u91ce\u575a\u7a7a\u6536\u7b97\u81f3\u653f\u57ce\u52b3\u843d\u94b1\u7279\u56f4\u5f1f\u80dc\u6559\u70ed\u5c55\u5305\u6b4c\u7c7b\u6e10\u5f3a\u6570\u4e61\u547c\u6027\u97f3\u7b54\u54e5\u9645\u65e7\u795e\u5ea7\u7ae0\u5e2e\u5566\u53d7\u7cfb\u4ee4\u8df3\u975e\u4f55\u725b\u53d6\u5165\u5cb8\u6562\u6389\u5ffd\u79cd\u88c5\u9876\u6025\u6797\u505c\u606f\u53e5\u533a\u8863\u822c\u62a5\u53f6\u538b\u6162\u53d4\u80cc\u7ec6";     //备选汉字的长度     int length = base.length();    //创建内存图像     BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);     // 获取图形上下文     Graphics g = image.getGraphics();    //创建随机类的实例     Random random = new Random();    // 设定图像背景色(因为是做背景，所以偏淡)     g.setColor(getRandColor(random,200,250));     g.fillRect(0, 0, width, height);    //备选字体     String[] fontTypes = {"\u5b8b\u4f53","\u65b0\u5b8b\u4f53","\u9ed1\u4f53","\u6977\u4f53","\u96b6\u4e66"};     int fontTypesLength = fontTypes.length;    //在图片背景上增加噪点     g.setColor(getRandColor(random,160,200));     g.setFont(new Font("Times New Roman",Font.PLAIN,14));     for (int i=0;i<6;i++)     {       g.drawString("*********************************************",0,5*(i+2));     }    //取随机产生的认证码(6个汉字)    //保存生成的汉字字符串     String sRand="";     for (int i=0;i<6;i++)     {       int start = random.nextInt(length);       String rand=base.substring(start,start+1);       sRand+=rand;             //设置字体的颜色       g.setColor(getRandColor(random,10,150));       //设置字体       g.setFont(new Font(fontTypes[random.nextInt(fontTypesLength)],Font.BOLD,18 + random.nextInt(6)));       //将此汉字画到图片上       g.drawString(rand,24*i+ 10 + random.nextInt(8),24);     }    //将认证码存入session     request.getSession().setAttribute("vcode",sRand);    g.dispose();    //输出图象到页面     ImageIO.write(image, "JPEG", response.getOutputStream());     }    public void shuzi_zimu(HttpServletRequest request, HttpServletResponse response) throws IOException{    response.setHeader("Pragma", "No-cache");     response.setHeader("Cache-Control", "no-cache");     response.setDateHeader("Expires", 0);     // 在内存中创建图象     int width = 80, height = 20;     BufferedImage image = new BufferedImage(width, height,       BufferedImage.TYPE_INT_RGB);     // 获取图形上下文     Graphics g = image.getGraphics();     //生成随机类     Random random = new Random();     // 设定背景色     g.setColor(getRandColor(200, 250));     g.fillRect(0, 0, width, height);     //设定字体     g.setFont(new Font("Times New Roman", Font.BOLD, 18));     //画边框     g.setColor(new Color(0, 0, 0));     g.drawRect(0, 0, width - 1, height - 1);     // 随机产生155条干扰线，使图象中的认证码不易被其它程序探测到     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);     }     // 取随机产生的认证码(4位数字)     String sRand = "";     for (int i = 0; i < 4; i++) {      String rand = null;      //随机生成数字或者字母      if (random.nextInt(10) > 5) {       rand = String.valueOf((char)(random         .nextInt(10) + 48));      } else {       rand = String.valueOf((char)(random         .nextInt(26) + 65));      }      sRand += rand;      // 将认证码显示到图象中      g.setColor(new Color(random.nextInt(80), random        .nextInt(80), random.nextInt(80)));      //调用函数出来的颜色相同，可能是因为种子太接近，所以只能直接生成      g.drawString(rand, 15 * i + 10, 16);     }     // 将认证码存入SESSION     request.getSession().setAttribute("vcode", sRand);     // 图象生效     g.dispose();     // 输出图象到页面     ImageIO.write(image, "JPEG", response.getOutputStream());    }}    

ImageVail.java

package servlet;import java.io.IOException;import java.io.PrintWriter;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import javax.servlet.http.HttpSession;public class ImageVali extends HttpServlet {private static final long serialVersionUID = 1L;@Overridepublic void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {String record = request.getParameter("record") ;HttpSession session = request.getSession() ;String vcode = (String)session.getAttribute("vcode") ;PrintWriter writer = response.getWriter() ;if(vcode.equalsIgnoreCase(record)){writer.println("success");}else{writer.println("failed");}}}

index.jsp

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%><%String path = request.getContextPath();String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";%><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html>  <head>    <base href="<%=basePath%>">        <title>My JSP 'index.jsp' starting page</title><meta http-equiv="pragma" content="no-cache"><meta http-equiv="cache-control" content="no-cache"><meta http-equiv="expires" content="0">    <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"><meta http-equiv="description" content="This is my page"><!--<link rel="stylesheet" type="text/css" href="styles.css">--><script type="text/javascript" src="js/jquery-1.4.js"></script><script type="text/javascript">var data2 ;function vali(){var ss = $("#ss").val() ;$.ajax({async:true,dataType:"text",type:"GET",url:"ss",data:{record:ss},success:function(data){alert(data) ;data2 = data ;}}) ;}function aa(){alert(data2) ;return false ;}</script>  </head>    <body>  <form method="get">  <input type="text" id="ss" onblur="vali();"/>    <img src="getcaptcha.sl" alt="验证码" name="checkImg" id="checkImg" style="position:relative; top:5px; left:20px; " onClick="document.getElementById('checkImg').src='getcaptcha.sl?temp='+ (new Date().getTime().toString(36)); return false"/>    <input type="button" value="提交" onclick = "aa();">      </form>  </body></html>

web.xml

<?xml version="1.0" encoding="UTF-8"?><web-app version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"><servlet>       <description>用于生成验证码</description>       <display-name>生成验证码</display-name>       <servlet-name>GetCaptcha</servlet-name>       <servlet-class>servlet.GetCaptcha</servlet-class>    </servlet>      <servlet-mapping>      <servlet-name>GetCaptcha</servlet-name>      <url-pattern>/getcaptcha.sl</url-pattern>    </servlet-mapping>  <servlet><servlet-name>checkData</servlet-name><servlet-class>servlet.ImageVali</servlet-class></servlet><servlet-mapping><servlet-name>checkData</servlet-name><url-pattern>/ss</url-pattern></servlet-mapping></web-app>