Java生成中文漢字隨機驗證碼

實現主要包含兩個類，一個是生成驗證碼，一個是判斷驗證碼輸入是否正確 實現原理比較簡單，將漢字和干擾線生成圖片并將漢字保存到session，前臺獲取每次生成的驗證碼圖片進行展示，驗證的時候就獲取文本框輸入的值傳到后臺與session值進行比較，功能就怎么簡單。

一、生成漢字驗證碼的類

package com.veryCode;

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.Random;
import javax.imageio.ImageIO;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**

生成隨機漢字驗證碼
@author feizi
@time 2015-1-30下午3:16:55
*/
public class DrawVeryCode extends HttpServlet {
private static final long serialVersionUID = -3002087466925846353L;
public static final int WIDTH = 120;
 public static final int HEIGHT = 30;
public void doGet(HttpServletRequest request,HttpServletResponse response)

     throws ServletException,IOException{
 this.doPost(request, response);

}
public void doPost(HttpServletRequest request,HttpServletResponse response)

 throws ServletException,IOException{
 request.setCharacterEncoding("utf-8");
 response.setContentType("text/html;charset=utf-8");

 //創建圖片緩存
 BufferedImage bi = new BufferedImage(WIDTH, HEIGHT, 
         BufferedImage.TYPE_INT_RGB);

 //獲得畫布
 Graphics g = bi.getGraphics();

 //設置背景顏色
 setBackGroundColor(g);

 //設置邊框
 setBorder(g);

 //繪制干擾線
 drawRandomLine(g);

 //產生隨機漢字驗證碼
 String randomChar = drawRandomChar((Graphics2D)g);//強制轉換

 //將產生的隨機漢字驗證碼存進session中進行保存
 request.getSession().setAttribute("veryCode", randomChar);

 //設置響應信息的類型為圖片類型
 response.setContentType("image/jpeg");

 //控制Http緩存，設置響應頭信息，防止瀏覽器緩存
 response.setDateHeader("expries", -1);
 response.setHeader("Cache-Control", "no-Cache");
 response.setHeader("Pargma", "no-Cache");

 //將驗證碼圖片寫到瀏覽器中
 ImageIO.write(bi, "jpg", response.getOutputStream());

}
/**

設置背景顏色
@param g
*/
private void setBackGroundColor(Graphics g){
 //設置背景顏色
 g.setColor(Color.WHITE);
 //填充區域
 g.fillRect(0, 0, WIDTH, HEIGHT);
}
/**

設置邊框
@param g
*/
private void setBorder(Graphics g){
 //設置邊框顏色
 g.setColor(Color.BLUE);
 //設置邊框區域
 g.drawRect(1, 1, WIDTH - 2, HEIGHT - 2);
}
/**

畫干擾線
@param g
*/
private void drawRandomLine(Graphics g){
 //設置干擾線的顏色
 g.setColor(Color.GREEN);
 //設置線條條數并開始畫線
 for (int i = 0; i < 40; i++) {

 int x1 = new Random().nextInt(WIDTH);
 int y1 = new Random().nextInt(HEIGHT);
 int x2 = new Random().nextInt(WIDTH);
 int y2 = new Random().nextInt(HEIGHT);

 //開始畫線
 g.drawLine(x1, y1, x2, y2);

}
}
/**

畫隨機漢字
@param g
*/
private String drawRandomChar(Graphics2D g){
 StringBuffer sb = new StringBuffer();
//設置顏色
 g.setColor(Color.RED);
//設置字體
 g.setFont(new Font("宋體", Font.BOLD, 20));
//準備常用漢字集
 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";


int x = 5;
//控制字數,最多4個字
 for (int i = 0; i < 4; i++) {

 //設置字體旋轉角度
 int degree = new Random().nextInt() % 30;

 //截取漢字
 String ch = base.charAt(new Random().nextInt(base.length())) + "";

 //追加到sb中
 sb.append(ch);

 //順時針旋轉
 g.rotate(degree * Math.PI / 180, x, 20);

 //開始畫漢字
 g.drawString(ch, x, 20);

 //逆時針旋轉
 g.rotate(-(degree * Math.PI / 180), x, 20);

 x += 30;

}
 return sb.toString();
}
public static void main(String[] args) {
 String s = "1234565236985";
 System.out.println(s.charAt(5) + "");
 System.out.println(new Random().nextInt());
}
}</pre>

二、驗證前臺頁面上輸入的驗證碼信息 
package com.veryCode;





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;
/**

驗證頁面上輸入的驗證碼信息
@author feizi
@time 2015-2-2上午8:14:22
*/
public class ResultServlet extends HttpServlet {
private static final long serialVersionUID = -4023881398470853660L;
public void doGet(HttpServletRequest request,HttpServletResponse response)

 throws ServletException,IOException{

 doPost(request, response);

}
public void doPost(HttpServletRequest request,HttpServletResponse response)

     throws ServletException,IOException{
 request.setCharacterEncoding("utf-8");
 response.setContentType("text/html;charset=utf-8");
 //產生的正確的驗證碼值
 String validateC = (String) request.getSession().getAttribute("veryCode");

 //瀏覽器中用戶輸入的驗證碼值
 String veryCode = request.getParameter("code");

 PrintWriter out = response.getWriter();
 if(null == veryCode || "".equals(veryCode)){
     out.println("請輸入驗證碼...");
 }else{
     if(validateC.equals(veryCode)){
         out.print(1);
     }else{
         out.println("對不起，驗證碼輸入錯誤...");
     }
 }

 out.flush();
 out.close();

}
}   </pre>

三，編寫前臺頁面，展示驗證碼信息 
<%@ page language="java" import="java.util.*" contentType="text/html; charset=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>隨機漢字驗證碼</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">

<script type="text/javascript" src="js/jquery-1.9.1.min.js"></script>
<script type="text/javascript" src="js/veryCode.js"></script>

</head>
<body>
    <div>
        <label>驗證碼：</label>
        <input id="veryCode" name="veryCode" type="text" class="yzm" value=""/>
        <input id="submit" value="提交" type="button" onclick="isRightCode();"/>
    </div>
    <br>
    <div>
        <img id="imgObj" alt="" src="DrawVeryCode">&nbsp;&nbsp;
        <a href="javascript:void(0);" onclick="changeImg()">換一張</a>
    </div>
    <br>
    <div>
        <span style="line-height: 38px; color: #FF0000; text-align: center;" colspan="2" id="info"></span>
    </div>
  </body>
</html></pre>

四，js文件 
/**


點擊切換一張驗證碼
*/
function changeImg(){
 var imgSrc = $('#imgObj');
 var src = imgSrc.attr('src');

//  alert("src:"+src);

imgSrc.attr('src',chgUrl(src));
$('#info').html('');

}
//時間戳處理
/**

為了使每次生成圖片不一致，即不讓瀏覽器讀緩存，所以需要加上時間戳

*/
function chgUrl(url){
 var timestamp = (new Date()).valueOf();
 url = url.substring(0,12);
//alert("timestamp:"+timestamp+">>>>url:"+url);
if(url.indexOf("&") >= 0){

 url = url + "×tamp=" + timestamp;

}else{

 url = url + "?timestamp=" + timestamp;

}
 return url;
}


/**

驗證輸入的驗證碼
*/
function isRightCode(){
 var code = $('#veryCode').val();
 code = "code=" + code;
 $.ajax({
 type:"POST",
 url:"ResultServlet",
 dataType:"text",
 data:code,
 success:function(data){
     //驗證以后處理提交信息或錯誤信息
     if(data == 1){
         $("#info").html("恭喜您，成功了！");
         return;
     }else{
         $("#info").html(data);
         return;
     }
 },
 error:function(){
     alert('鏈接出現錯誤！');
 }

 });

}</pre>

五，運行效果 

 
 
ok，到這里基本上全部已經好了，如果想實現更加復雜一點的可以再自行進行研究擴展。。。



來自：http://blog.csdn.net/hu1991die/article/details/43792027