java验证码代码

1、java 验证码代码（转）产生图片 servletimportjava.awt.Color;importjava.awt.Font;importjava.awt.Graphics2D;importjava.awt.image.Bufferedlmage;importjava.util.Random;importjavax.imageio.ImagelO;importjavax.servlet.ServletException;importjavax.servlet.ServletOutputStream;importjavax.servlet.http.HttpServlet;importja

2、vax.servlet.http.HttpServletRequest;importjavax.servlet.http.HttpServletResponse;importjavax.servlet.http.HttpSession;/* Packagename:com.skcc.sample.actionFilename:VerifyCodeServlet.java* Author:AdministratorDate:2008-9-4Description:VerifyCodeServlet*/publicclassVerifyCodeServletextendsHttpServlet/*

3、/*验证码图片的宽度。*/privateintwidth=60;/*验证码图片的高度。*/privateintheight=20;/*验证码字符个数privatestaticfinallongserialVersionUID=1L;J*/private/*xx*/private/*intcodeCount=4;intxx=0;*字体高度*/privateintfontHeight/*codeY*/privateintcodeY/*codeSequence*/char codeSequenceABC,DEFG,HW,K,L,M,N:,O,P,Q,R,S,T,UX,Y,Z,0,1,2,3,4,5,

4、6,7IV89;/*初始化验证图片属性*/publicvoidinit()throwsServletException/从web.xml中获取初始信息宽度StringstrWidth=/高度StringstrHeight=/字符个数StringstrCodeCount=thisthis.getInitParameter(.getInitParameter(this.getInitParameter(widthheight/将配置的信息转换成数值tryif(strWidth!=null&strWidth.length()!=0)width=Integer.parseInt(strWidt

5、h);););codeCount);null&strCodeCount.length()!=0)parseInt(strCodeCount);)catch(NumberFormatExceptione)e.printStackTrace();xx=width/(codeCount+1);codeY=height-4;Graphics2Dgd=buffImg.createGraphics();/创建一个随机数生成器类/创建字体，字体的大小应该根据图片的高度来定。/设置字体。gd.setFont(font);)if(strHeight!=null&strHeight.length(

6、)!=0)height=Integer.parseInt(strHeight);Fontfont=newFont(Fixedsys,Font.PLAIN,fontHeight);)if(strCodeCount!=codeCount=Integer.fontHeightheight-2;/*paramparamreq*/throwsthrowsrespServletExceptionjava.io.IOExceptionprotectedresp)voidservice(HttpServletRequestreq,HttpServletResponsethrowsServletExceptio

7、n,java.io.IOException/定义图像 bufferBufferedImagebuffImg=BufferedImage.newBufferedImage(TYPE_INT_RGB);widthheightRandomrandom=newRandom();/将图像填充为白色gd.setColor(Color.gd.fillRect(0,0,WHITE);width,height);BLACK);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。gd.setColor(Color.BLACK);for(inti=0;i160;i

8、+)intx=random.nextInt(width);inty=random.nextInt(height);intxl=random.nextInt(12);intyl=random.nextInt(12);gd.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。StringBufferrandomCode=newStringBuffer();intred=0,green=0,blue=0;/随机产生 codeCount 数字的验证码。for(inti=0;icodeCount;i+)/得到随机产生的验证码数字。S

9、tringstrRand=String.valueOf(codeSequencerandom.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。gd.setColor(newColor(red,green,blue);gd.drawString(strRand,(i+1)*xx,codeY);/将产生的四个随机数组合在一起。randomCode.append(str

10、Rand);)/将四位数字的验证码保存到 Session 中。HttpSessionsession=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);/画边框。gd.setColor(Color.gd.drawRect(0,0,/* ThedoGetmethodoftheservle

11、t.* Thismethodiscalledwhenaformhasitstagvaluemethodequalstoget.* paramrequest* therequestsendbytheclienttotheserver* paramresponse* theresponsesendbytheservertotheclient* throwsServletExceptionresp.setContentType(image/jpeg);/将图像输出到 Servlet 输出流中。ServletOutputStreamsos=resp.getOutputStream();ImageIO.

12、write(buffImg,jpeg,sos);sos.close();产生结果 servletimportjava.io.IOException;importjava.io.PrintWriter;importjavax.servlet.ServletException;importjavax.servlet.http.HttpServlet;importjavax.servlet.http.HttpServletRequest;importjavax.servlet.http.HttpServletResponse;/*Packagename:com.skcc.sample.actionF

13、ilename:ResultServlet.javaAuthor:*AdministratorDate:2008-9-4Description:ResultServlet*/publicclassResultServletextendsHttpServlet/*/privatestaticfinallongserialVersionUID=1L;* ifanerroroccurred* throwslOException* ifanerroroccurred* /publicvoiddoGet(HttpServletRequestrequest,HttpServletResponserespo

14、nse)throwsServletException,IOExceptiondoPost(request,response);/* ThedoPostmethodoftheservlet.* Thismethodiscalledwhenaformhasitstagvaluemethodequalsto*post.* paramrequesttherequestsendbytheclienttotheserver* paramresponsetheresponsesendbytheservertotheclient* throwsServletExceptionifanerroroccurred

15、* throwslOException* ifanerroroccurred* /publicvoiddoPost(HttpServletRequestrequest,HttpServletResponseresponse)throwsServletException,lOExceptionresponse.setContentType(text/html;charset=utf-8);StringvalidateC=(String)request.getSession().getAttribute(validateCode);StringveryCode=request.getParamet

16、er(veryCode);PrintWriterout=response.getWriter();if(veryCode=null|.equals(veryCode)out.println(验证码为空);elseif(validateC.equals(veryCode)out.println(验证码正确);elseout.println(验证码错误);)js 文件functionchangeImg()varimgSrc=$(#imgObj);varsrc=imgSrc.attr(src);imgSrc.attr(src,chgUrl(src);)/时间戳/为了使每次生成图片不一致，即不让浏览器

17、读缓存，所以需要加上时间戳functionchgUrl(url)vartimestamp=(newDate().valueOf();url=url.substring(0,17);&)=0)?atamp=+timestamp;?timestamp=+timestamp;returnurl;functionisRightCode()varcode=$(#veryCode).attr(value);code=c=+code;$.ajax(type:POST,url:resultServlet,data:code,success:callback);functioncallback(data

18、)$(#info).html(data);页面 verifyCode.jspout.flush();out.close();if(url.indexOf(url=url+elseurl=url+%pagelanguage=javapageEncodingPUBLIC-/W3C/DTDHTML4.01Transitional/EN/TR/html4/loose.dtdmetahttp-equiv=Content-Typecontent=text/html;charset=UTF-8scriptscripttestverifycodesrc=js/verifyCode.jssrc=js/jquery.js/script/titleinput/换一张input=isRightCode()/最后记得配好 web.xmlservlet-nameservlet-nameservlet-classservlet-mappingservlet-nameurl-patte