java开发篇-验证码

package com.oumyye.util;/* * 作者：oumyye */import java.awt.Color;import java.awt.Font;import java.awt.Graphics;import java.awt.image.BufferedImage;import java.util.Random;import javax.imageio.ImageIO;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import javax.servlet.http.HttpSession;public class RandomValidateCode {    public static final String RANDOMCODEKEY = "RANDOMVALIDATECODEKEY";//放到session中的key    private Random random = new Random();    private String randString = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";//随机产生的字符串        private int width = 120;//图片宽    private int height = 40;//图片高    private int lineSize = 40;//干扰线数量    private int stringNum = 6;//随机产生字符数量    /*     * 获得字体     */    private Font getFont(){        return new Font("Fixedsys",Font.CENTER_BASELINE,20);    }    /*     * 获得颜色     */    private Color getRandColor(int fc,int bc){        if(fc > 255)            fc = 255;        if(bc > 255)            bc = 255;        int r = fc + random.nextInt(bc-fc-16);        int g = fc + random.nextInt(bc-fc-14);        int b = fc + random.nextInt(bc-fc-18);        return new Color(r,g,b);    }    /**     * 生成随机图片     */    public void getRandcode(HttpServletRequest request,            HttpServletResponse response) {        HttpSession session = request.getSession();        //BufferedImage类是具有缓冲区的Image类,Image类是用于描述图像信息的类        BufferedImage image = new BufferedImage(width,height,BufferedImage.TYPE_INT_BGR);        Graphics g = image.getGraphics();//产生Image对象的Graphics对象,改对象可以在图像上进行各种绘制操作        g.fillRect(0, 0, width, height);        g.setFont(new Font("Times New Roman",Font.ROMAN_BASELINE,20));        g.setColor(getRandColor(100, 133));        //绘制干扰线        for(int i=0;i<=lineSize;i++){            drowLine(g);        }        //绘制随机字符        String randomString = "";        for(int i=1;i<=stringNum;i++){            randomString=drowString(g,randomString,i);        }        session.removeAttribute(RANDOMCODEKEY);        session.setAttribute(RANDOMCODEKEY, randomString);        System.out.println(randomString);        g.dispose();        try {            ImageIO.write(image, "JPEG", response.getOutputStream());//将内存中的图片通过流动形式输出到客户端        } catch (Exception e) {            e.printStackTrace();        }    }    /*     * 绘制字符串     */    private String drowString(Graphics g,String randomString,int i){        g.setFont(getFont());        g.setColor(new Color(random.nextInt(101),random.nextInt(111),random.nextInt(121)));        String rand = String.valueOf(getRandomString(random.nextInt(randString.length())));        randomString +=rand;        g.translate(random.nextInt(3), random.nextInt(3));        g.drawString(rand, 13*i, 30);        return randomString;    }    /*     * 绘制干扰线     */    private void drowLine(Graphics g){        int x = random.nextInt(width);        int y = random.nextInt(height);        int xl = random.nextInt(10);        int yl = random.nextInt(15);        g.drawLine(x, y, x+xl, y+yl);    }    /*     * 获取随机的字符     */    public String getRandomString(int num){        return String.valueOf(randString.charAt(num));    }}

package com.oumyye.servlet;/** * 作者：oumyye */import java.io.IOException;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import com.oumyye.util.RandomValidateCode;public class ImageServlet extends HttpServlet {    /**     * Constructor of the object.     */    public ImageServlet() {        super();    }    /**     * Destruction of the servlet. <br>     */    public void destroy() {        super.destroy(); // Just puts "destroy" string in log        // Put your code here    }    /**     * The doGet method of the servlet. <br>     *     * This method is called when a form has its tag value method equals to get.     *      * @param request the request send by the client to the server     * @param response the response send by the server to the client     * @throws ServletException if an error occurred     * @throws IOException if an error occurred     */    public void doGet(HttpServletRequest request, HttpServletResponse response)            throws ServletException, IOException {         response.setContentType("image/jpeg");//设置相应类型,告诉浏览器输出的内容为图片            response.setHeader("Pragma", "No-cache");//设置响应头信息，告诉浏览器不要缓存此内容            response.setHeader("Cache-Control", "no-cache");            response.setDateHeader("Expire", 0);            RandomValidateCode randomValidateCode = new RandomValidateCode();            try {                randomValidateCode.getRandcode(request, response);//输出图片方法            } catch (Exception e) {                e.printStackTrace();            }    }    /**     * The doPost method of the servlet. <br>     *     * This method is called when a form has its tag value method equals to post.     *      * @param request the request send by the client to the server     * @param response the response send by the server to the client     * @throws ServletException if an error occurred     * @throws IOException if an error occurred     */    public void doPost(HttpServletRequest request, HttpServletResponse response)            throws ServletException, IOException {         doGet(request, response);    }    /**     * Initialization of the servlet. <br>     *     * @throws ServletException if an error occurs     */    public void init() throws ServletException {        // Put your code here    }}

<?xml version="1.0" encoding="UTF-8"?><web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" version="3.0">  <display-name>0001web</display-name>   <servlet>    <description>ImageCreate</description>    <display-name>ImageCreate</display-name>    <servlet-name>ImageServlet</servlet-name>    <servlet-class>com.oumyye.servlet.ImageServlet</servlet-class>  </servlet>  <servlet-mapping>    <servlet-name>ImageServlet</servlet-name>    <url-pattern>/servlet/ImageServlet</url-pattern>  </servlet-mapping></web-app>

<!DOCTYPE html><html>  <head>    <title>验证码</title>    <!-- Bootstrap -->    <meta charset="utf-8">     <link href="bootstrap/css/bootstrap.min.css" rel="stylesheet" media="screen">    <link href="bootstrap/css/bootstrap-responsive.min.css" rel="stylesheet" media="screen">    <link href="assets/styles.css" rel="stylesheet" media="screen">     <!-- HTML5 shim, for IE6-8 support of HTML5 elements -->    <!--[if lt IE 9]>      <script src="http://html5shim.googlecode.com/svn/trunk/html5.js"></script>    <![endif]-->    <script src="vendor/modernizr-2.6.2-respond-1.1.0.min.js"></script>        <script type="text/javascript">    function refresh(obj) {        obj.src = "servlet/ImageServlet?"+Math.random();    }    </script>          </head>  <body id="login">           <input type="text" placeholder="验证码" name="imageCode" id="randomCode" onblur="checkImage()" style="width:58%;" required>        <img title="点击更换" onclick="javascript:refresh(this);" src="servlet/ImageServlet" style="margin-top:-16px;"><br/>        <div id="checkBody">        </div>    <!-- /container -->    <script src="vendors/jquery-1.9.1.min.js"></script>    <script src="bootstrap/js/bootstrap.min.js"></script>    <script type="text/javascript">        var xmlHttp ;    function createXMLHttpRequest(){        if(window.ActiveXOBject){            xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");        }else if(window.XMLHttpRequest){            xmlHttp = new XMLHttpRequest();        }    }            function checkImage(){        var  imageCode = document.getElementById("randomCode").value;        if(imageCode==""||imageCode==null){            document.getElementById("checkBody").innerHTML="" +            "<div class='alert alert-danger' role='alert'>请输入验证码!</div> " ;            document.getElementById("randomCode").focus() ;            return false ;        }                var url = "userCheckCodeAction.action?imageCode="+imageCode;        createXMLHttpRequest();        xmlHttp.onreadystatechange = processorCheckImage;        xmlHttp.open("POST",url,true);        xmlHttp.send();    }        function processorCheckImage(){        var responseContext ;        if(xmlHttp.readyState==4){            if(xmlHttp.status==200){                responseContext = xmlHttp.responseText;                                if(responseContext.indexOf("failure")!=-1){                                        document.getElementById("checkBody").innerHTML="" +                    "<div class='alert alert-danger' role='alert'>验证码错误!</div> " ;                    document.getElementById("randomCode").focus() ;                    return false ;                }else{                    document.getElementById("checkBody").innerHTML="" +                            "<div class='alert alert-success' role='alert'>验证码正确 !</div> " ;                                                document.getElementById("submitBtn").innerHTML="" +                                    "<button class='btn btn-large btn-primary' type='submit' style='width:80%;' >登  陆</button>" ;                    return true ;        }    }}}    </script>          </body></html>