关于kaptcha介绍，我们就不说了，网上一堆的资料。
使用kaptcha可以方便的配置：
验证码的字体
验证码字体的大小
验证码字体的字体颜色
验证码内容的范围(数字，字母，中文汉字！)
验证码图片的大小，边框，边框粗细，边框颜色
验证码的干扰线(可以自己继承com.google.code.kaptcha.NoiseProducer写一个自定义的干扰线)
验证码的样式(鱼眼样式、3D、普通模糊……当然也可以继承com.google.code.kaptcha.GimpyEngine自定义样式)
下面介绍一下用法:
1.首先去官网下载jar:http://code.google.com/p/kaptcha/
2.建立一个web项目，导入 kaptcha-2.3.jar 到环境变量中。
网盘下载jar包： http://yunpan.cn/cdjzkrjKgQ7eD 访问密码 754f
（1）在applicationContext.xml中配置
<bean id="captchaProducer" class="com.google.code.kaptcha.impl.DefaultKaptcha"> <property name="config"> <bean class="com.google.code.kaptcha.util.Config"> <constructor-arg> <props> <prop key="kaptcha.border">no</prop> <prop key="kaptcha.border.color">105,179,90</prop> <prop key="kaptcha.textproducer.font.color">red</prop> <prop key="kaptcha.image.width">250</prop> <prop key="kaptcha.textproducer.font.size">90</prop> <prop key="kaptcha.image.height">90</prop> <prop key="kaptcha.session.key">code</prop> <prop key="kaptcha.textproducer.char.length">4</prop> <prop key="kaptcha.textproducer.font.names">宋体,楷体,微软雅黑</prop> </props> </constructor-arg> </bean> </property> </bean>
（2）controller 的实现
package com.souvc.app.base.captcha;
import java.awt.image.BufferedImage;
import javax.imageio.ImageIO;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.servlet.ModelAndView;
import com.google.code.kaptcha.Constants;
import com.google.code.kaptcha.Producer;
/**
* 防止Captcha机器人登陆
* @author liuwang
*
*/
@Controller
@RequestMapping("/kaptcha/*")
public class CaptchaController {
@Autowired
private Producer captchaProducer = null;
@RequestMapping
public ModelAndView getKaptchaImage(HttpServletRequest request, HttpServletResponse response) throws Exception {
HttpSession session = request.getSession();
String code = (String)session.getAttribute(Constants.KAPTCHA_SESSION_KEY);
System.out.println("******************验证码是: " + code + "******************");
response.setDateHeader("Expires", 0);
// Set standard HTTP/1.1 no-cache headers.
response.setHeader("Cache-Control", "no-store, no-cache, must-revalidate");
// Set IE extended HTTP/1.1 no-cache headers (use addHeader).
response.addHeader("Cache-Control", "post-check=0, pre-check=0");
// Set standard HTTP/1.0 no-cache header.
response.setHeader("Pragma", "no-cache");
// return a jpeg
response.setContentType("image/jpeg");
// create the text for the image
String capText = captchaProducer.createText();
// store the text in the session
session.setAttribute(Constants.KAPTCHA_SESSION_KEY, capText);
// create the image with the text
BufferedImage bi = captchaProducer.createImage(capText);
ServletOutputStream out = response.getOutputStream();
// write the data out
ImageIO.write(bi, "jpg", out);
try {
out.flush();
} finally {
out.close();
}
return null;
}
}
（3）jsp代码
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<script type="text/javascript" src="js/jquery.js"></script>
<script type="text/javascript" src="js/functions.js"></script>
<title>测试页面</title>
<script type="text/javascript">
$(function(){
$('#kaptchaImage').click(function () {//生成验证码
$(this).hide().attr('src', './kaptcha/getKaptchaImage.do?' + Math.floor(Math.random()*100) ).fadeIn();
event.cancelBubble=true;
});
});
window.onbeforeunload = function(){
//关闭窗口时自动退出
if(event.clientX>360&&event.clientY<0||event.altKey){
alert(parent.document.location);
}
};
function changeCode() {
$('#kaptchaImage').hide().attr('src', './kaptcha/getKaptchaImage.do?' + Math.floor(Math.random()*100) ).fadeIn();
event.cancelBubble=true;
}
</script>
</head>
<body>
<div class="chknumber">
<label>验证码:
<input name="kaptcha" type="text" id="kaptcha" maxlength="4" class="chknumber_input" />
</label>
<br />
<img src="./kaptcha/getKaptchaImage.do" id="kaptchaImage" style="margin-bottom: -3px"/>
<a href="#" onclick="changeCode()">看不清?换一张</a>
</div>
</body>
</html>
温馨提示：
获取验证码的关键语句，如下：
String code =(String)session.getAttribute(com.google.code.kaptcha.Constants.KAPTCHA_SESSION_KEY);
（4） kaptcha可配置项
kaptcha.border 是否有边框 默认为true 我们可以自己设置yes，no
kaptcha.border.color 边框颜色 默认为Color.BLACK
kaptcha.border.thickness 边框粗细度 默认为1
kaptcha.producer.impl 验证码生成器 默认为DefaultKaptcha
kaptcha.textproducer.impl 验证码文本生成器 默认为DefaultTextCreator
kaptcha.textproducer.char.string 验证码文本字符内容范围 默认为abcde2345678gfynmnpwx
kaptcha.textproducer.char.length 验证码文本字符长度 默认为5
kaptcha.textproducer.font.names 验证码文本字体样式 默认为new Font("Arial", 1, fontSize), new Font("Courier", 1, fontSize)
kaptcha.textproducer.font.size 验证码文本字符大小 默认为40
kaptcha.textproducer.font.color 验证码文本字符颜色 默认为Color.BLACK
kaptcha.textproducer.char.space 验证码文本字符间距 默认为2
kaptcha.noise.impl 验证码噪点生成对象 默认为DefaultNoise
kaptcha.noise.color 验证码噪点颜色 默认为Color.BLACK
kaptcha.obscurificator.impl 验证码样式引擎 默认为WaterRipple
kaptcha.word.impl 验证码文本字符渲染 默认为DefaultWordRenderer
kaptcha.background.impl 验证码背景生成器 默认为DefaultBackground
kaptcha.background.clear.from 验证码背景颜色渐进 默认为Color.LIGHT_GRAY
kaptcha.background.clear.to 验证码背景颜色渐进 默认为Color.WHITE
kaptcha.image.width 验证码图片宽度 默认为200
kaptcha.image.height 验证码图片高度 默认为50
（5）验证验证码是否正确的方法：
@RequestMapping(value = "/checkRandCode", method = RequestMethod.GET)
public void checkRandCode(HttpServletRequest request,
HttpServletResponse response) {
Map<String, Object> map = new HashMap<String, Object>();
try {
String randCode = request.getParameter("randCode");
logger.info("randCode: " +randCode);
String status = "0";
String code = (String)request.getSession().getAttribute(com.google.code.kaptcha.Constants.KAPTCHA_SESSION_KEY);
if(randCode.toLowerCase().equals(code.toLowerCase()))status="1";
map.put("status", status);
map.put("description", "");
String data = JSONObject.fromObject(map).toString();
logger.info("返回给页面的数据为: " + data);
response.getWriter().print(data);
response.getWriter().flush();
response.getWriter().close();
} catch (Exception ex) {
logger.error(ex.getMessage(), ex);
}
(6) 默认值
另一篇实用的 kaptcha 验证码在spring mvc 中的使用 教程
配置web.xml文件
<!--Kaptcha 验证码 --><!-- <servlet> <servlet-name>kaptcha</servlet-name> <servlet-class>com.google.code.kaptcha.servlet.KaptchaServlet</servlet-class> <init-param> <param-name>kaptcha.border</param-name> <param-value>no</param-value> </init-param> <init-param> <param-name>kaptcha.border.color</param-name> <param-value>105,179,90</param-value> </init-param> <init-param> <param-name>kaptcha.textproducer.font.color</param-name> <param-value>red</param-value> </init-param> <init-param> <param-name>kaptcha.image.width</param-name> <param-value>250</param-value> </init-param> <init-param> <param-name>kaptcha.image.height</param-name> <param-value>90</param-value> </init-param> <init-param> <param-name>kaptcha.textproducer.font.size</param-name> <param-value>70</param-value> </init-param> <init-param> <param-name>kaptcha.session.key</param-name> <param-value>code</param-value> </init-param> <init-param> <param-name>kaptcha.textproducer.char.length</param-name> <param-value>4</param-value> </init-param> <init-param> <param-name>kaptcha.textproducer.font.names</param-name> <param-value>宋体,楷体,微软雅黑</param-value> </init-param> </servlet>
Xml代码
<servlet-mapping> <servlet-name>kaptcha</servlet-name> <url-pattern>/ClinicCountManager/kaptcha.jpg</url-pattern> </servlet-mapping>
jsp 页面使用
<table>
<tr>
<td><img src="/ClinicCountManager/kaptcha.jpg"></td>
<td valign="top">
<form method="POST">
<br>sec code:<input type="text" name="kaptchafield"><br />
<input type="submit" name="submit">
</form>
</td>
</tr>
</table>
<br /><br /><br /><br />
<%
String c = (String)session.getAttribute(com.google.code.kaptcha.Constants.KAPTCHA_SESSION_KEY);
String parm = (String) request.getParameter("kaptchafield");
out.println("Parameter: " + parm + " ? Session Key: " + c + " : ");
if (c != null && parm != null) {
if (c.equals(parm)) {
out.println("<b>true</b>");
} else {
out.println("<b>false</b>");
}
%>
上面的配置在普通jsp环境下面是有效的，如果在spring mvc环境下，则取不到session值，对于sping mvc环境验证码配置如下：
不用在web.xml进行相关配置，在applicationContext.xml中配置
<bean id="captchaProducer" class="com.google.code.kaptcha.impl.DefaultKaptcha"> <property name="config"> <bean class="com.google.code.kaptcha.util.Config"> <constructor-arg> <props> <prop key="kaptcha.border">no</prop> <prop key="kaptcha.border.color">105,179,90</prop> <prop key="kaptcha.textproducer.font.color">red</prop> <prop key="kaptcha.image.width">250</prop> <prop key="kaptcha.textproducer.font.size">90</prop> <prop key="kaptcha.image.height">90</prop> <prop key="kaptcha.session.key">code</prop> <prop key="kaptcha.textproducer.char.length">4</prop> <prop key="kaptcha.textproducer.font.names">宋体,楷体,微软雅黑</prop> </props> </constructor-arg> </bean> </property> </bean>
新建生成图片控制类
import java.awt.image.BufferedImage;
import javax.imageio.ImageIO;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.servlet.ModelAndView;
import com.google.code.kaptcha.Constants;
import com.google.code.kaptcha.Producer;
@Controller
@RequestMapping("/")
public class CaptchaImageCreateController {
private Producer captchaProducer = null;
@Autowired
public void setCaptchaProducer(Producer captchaProducer) {
this.captchaProducer = captchaProducer;
}
@RequestMapping("/captcha-image")
public ModelAndView handleRequest(HttpServletRequest request, HttpServletResponse response) throws Exception {
response.setDateHeader("Expires", 0);
// Set standard HTTP/1.1 no-cache headers.
response.setHeader("Cache-Control", "no-store, no-cache, must-revalidate");
// Set IE extended HTTP/1.1 no-cache headers (use addHeader).
response.addHeader("Cache-Control", "post-check=0, pre-check=0");
// Set standard HTTP/1.0 no-cache header.
response.setHeader("Pragma", "no-cache");
// return a jpeg
response.setContentType("image/jpeg");
// create the text for the image
String capText = captchaProducer.createText();
// store the text in the session
request.getSession().setAttribute(Constants.KAPTCHA_SESSION_KEY, capText);
// create the image with the text
BufferedImage bi = captchaProducer.createImage(capText);
ServletOutputStream out = response.getOutputStream();
// write the data out
ImageIO.write(bi, "jpg", out);
try {
out.flush();
} finally {
out.close();
}
return null;
}
}
前台调用方式
<div class="chknumber">
<label>验证码：
<input name="kaptcha" type="text" id="kaptcha" maxlength="4" class="chknumber_input" />
</label>
<img src="/ClinicCountManager/captcha-image.do" width="55" height="20" id="kaptchaImage" style="margin-bottom: -3px"/>
<script type="text/javascript">
$(function(){
$('#kaptchaImage').click(function () {//生成验证码
$(this).hide().attr('src', '/ClinicCountManager/captcha-image.do?' + Math.floor(Math.random()*100) ).fadeIn(); })
});
</script>
</div>
取验证码的方式
String code = (String)session.getAttribute(com.google.code.kaptcha.Constants.KAPTCHA_SESSION_KEY);
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时间： 2024-09-16 17:54:55