Jcaptcha和Kaptcha验证码使用入门

原文地址：http://www.v5cn.cn/?p=157

一、jcaptcha验证码使用

jcaptcha使用默认样式生成的验证码比较难以识别，所以需要自定义验证码的样式，包括，背景色、背景大小、字体、字体大小、生成的字符数等。相对与kaptcha比较复杂。

1.1、纯代码实现jcaptcha验证码

1、首先创建一个javaWeb工程添加jcaptcha包和它所依赖的包，添加完成后：

2、创建一个jcaptcha单例的Service类，这里是设置验证码样式的关键部分，代码如下：

package cn.v5cn.jcaptchatest.custom; import java.awt.Font; import com.octo.captcha.CaptchaFactory;import com.octo.captcha.component.image.backgroundgenerator.UniColorBackgroundGenerator;import com.octo.captcha.component.image.color.RandomRangeColorGenerator;import com.octo.captcha.component.image.fontgenerator.RandomFontGenerator;import com.octo.captcha.component.image.textpaster.RandomTextPaster;import com.octo.captcha.component.image.wordtoimage.ComposedWordToImage;import com.octo.captcha.component.word.FileDictionary;import com.octo.captcha.component.word.wordgenerator.ComposeDictionaryWordGenerator;import com.octo.captcha.engine.GenericCaptchaEngine;import com.octo.captcha.image.gimpy.GimpyFactory;import com.octo.captcha.service.image.ImageCaptchaService;import com.octo.captcha.service.multitype.GenericManageableCaptchaService; public class CaptchaServiceSingleton {    private static ImageCaptchaService service = null;     public static ImageCaptchaService getService(){        if(service == null)            service = generatorCaptchaService();        return service;    }    /**     * 根据SpringBean的配置文件编写的代码实现     * */    public static ImageCaptchaService generatorCaptchaService(){        //生成随机颜色，参数分别表示RGBA的取值范围        RandomRangeColorGenerator textColor = new RandomRangeColorGenerator(new int[]{0,255},new int[]{0,180},new int[]{0,210},new int[]{255,255});        //随机文字多少和颜色，参数1和2表示最少生成多少个文字和最多生成多少个        RandomTextPaster randomTextPaster = new RandomTextPaster(4, 5, textColor,true);        //生成背景的大小这里是宽85高40的图片，也可以设置背景颜色和随机背景颜色，这里使用默认的白色        UniColorBackgroundGenerator colorbgGen = new UniColorBackgroundGenerator(85,40);        //随机生成的字体大小和字体类型，参数1和2表示最小和最大的字体大小，第三个表示随机的字体        RandomFontGenerator randomFontGenerator = new RandomFontGenerator(20, 25, new Font[]{new Font("Arial", 0, 10),new Font("Tahoma",0,10)});        //结合上面的对象构件一个从文本生成图片的对象        ComposedWordToImage cwti = new ComposedWordToImage(randomFontGenerator,colorbgGen,randomTextPaster);        //随机文本的字典，这里是使用jcaptcha-1.0-all.jar中的文本字典，字典名称为toddlist.properties        ComposeDictionaryWordGenerator cdwg = new ComposeDictionaryWordGenerator(new FileDictionary("toddlist"));         GimpyFactory gf = new GimpyFactory(cdwg, cwti);         GenericCaptchaEngine gce = new GenericCaptchaEngine(new CaptchaFactory[]{gf});        //返回一个Service对象，这里180是验证码存在的时间，单位是秒，200000是最大存储大小        return new GenericManageableCaptchaService(gce,180,200000,75000);    }}

每一句代码都有注释，这里就不多说了。

3、创建一个生成验证码的Servlet，代码如下：

package cn.v5cn.jcaptchatest.custom; import java.awt.image.BufferedImage;import java.io.ByteArrayOutputStream;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 com.sun.image.codec.jpeg.JPEGCodec;import com.sun.image.codec.jpeg.JPEGImageEncoder; public class CustomServlet extends HttpServlet {     private static final long serialVersionUID = 169310818225761427L;         @Override    protected void doGet(HttpServletRequest req, HttpServletResponse resp)            throws ServletException, IOException {        byte[] captChallengeAsJpeg = null;                 ByteArrayOutputStream jpegOutputStream = new ByteArrayOutputStream();                 String captchaId = req.getSession().getId();        BufferedImage challenge = CaptchaServiceSingleton.getService().getImageChallengeForID(captchaId,req.getLocale());                 JPEGImageEncoder jpegEncoder = JPEGCodec.createJPEGEncoder(jpegOutputStream);        jpegEncoder.encode(challenge);                 captChallengeAsJpeg = jpegOutputStream.toByteArray();                  resp.setHeader("Cache-Control", "no-store");         resp.setHeader("Pragma", "no-cache");         resp.setDateHeader("Expires", 0);         resp.setContentType("image/jpeg");                   ServletOutputStream respOutputStream = resp.getOutputStream();         respOutputStream.write(captChallengeAsJpeg);         respOutputStream.flush();         respOutputStream.close();    }}

4、在Web.xml中注册这个Servlet，代码如下：

<servlet>    <servlet-name>generateValidateCode</servlet-name>    <servlet-class>cn.v5cn.jcaptchatest.custom.CustomServlet</servlet-class>  </servlet>  <servlet-mapping>    <servlet-name>generateValidateCode</servlet-name>    <url-pattern>/cgvc</url-pattern>  </servlet-mapping>

5、编写一个使用验证码的页面，代码如下：

<form action="valiServlet" method="post">    <input type="text" name="customgvc">    <img id="vcode" title="点击更换" alt="验证图片" style="vertical-align: middle;" src="cgvc" height="30" width="80">    <input type="submit" value="提交"></form>

6、编写一个验证Servlet并在web.xml中注册，代码分别如下：

package cn.v5cn.jcaptchatest.custom; import java.io.IOException; import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse; public class ValidateServlet extends HttpServlet {     private static final long serialVersionUID = -7173743572400866269L;         @Override    protected void doPost(HttpServletRequest req, HttpServletResponse resp)            throws ServletException, IOException {        String captchaId = req.getSession().getId();                 String validateCode = req.getParameter("customgvc");                 boolean validateResult = CaptchaServiceSingleton.getService().validateResponseForID(captchaId, validateCode);        if(validateResult)            resp.sendRedirect("success.html");        else            resp.sendRedirect("fail.html");    }}

 

<servlet>    <servlet-name>validatServlet</servlet-name>    <servlet-class>cn.v5cn.jcaptchatest.custom.ValidateServlet</servlet-class>  </servlet>  <servlet-mapping>    <servlet-name>validatServlet</servlet-name>    <url-pattern>/valiServlet</url-pattern>  </servlet-mapping>

7、运行会看到验证码如下：

8、输入验证码点击提交，看是否可以验证通过，如果一切正常的话Session中的和提交的是一致的。

1.2、使用Spring配置jcaptha验证码

1、创建一个javaWeb工程并加入Spring和jcaptcha的包。添加完成后的包依赖如下：

2、在web.xml中配置Spring代码如下：

<context-param>    <param-name>contextConfigLocation</param-name>    <param-value>        /WEB-INF/spring-jcaptcha.xml    </param-value>  </context-param>  <listener>    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>  </listener>

3、在WEB-INF中创建spring-jcaptcha.xml的SpringBean配置文件，代码如下：

<?xml version="1.0" encoding="UTF-8"?><beans xmlns="http://www.springframework.org/schema/beans"    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.2.xsd">     <!-- 构建生成图片服务 -->    <bean id="imageCaptchaService"  class="com.octo.captcha.service.multitype.GenericManageableCaptchaService">        <constructor-arg index="0" ref="imageEngine"/>        <constructor-arg index="1" value="180"/>        <constructor-arg index="2" value="200000"/>        <constructor-arg index="3" value="75000"/>    </bean>         <!-- 构建生成图片引擎，可以传入多个ImageCaptchaFactory工厂 -->    <bean id="imageEngine" class="com.octo.captcha.engine.GenericCaptchaEngine">        <constructor-arg index="0">                <list>                    <ref bean="imageCaptchaFactory"/>                </list>        </constructor-arg>    </bean>    <!-- 构件图片工厂 ，图片工厂包括FishEyeFactory和GimpyFactory 它们都继承自ImageCaptchaFactory抽象类-->    <bean id="imageCaptchaFactory" class="com.octo.captcha.image.gimpy.GimpyFactory" >        <constructor-arg><ref bean="wordgen"/></constructor-arg>        <constructor-arg><ref bean="wordtoimage"/></constructor-arg>     </bean>           <!-- 构件验证码上的文本生成类 -->     <bean id="wordgen" class="com.octo.captcha.component.word.wordgenerator.ComposeDictionaryWordGenerator" >        <constructor-arg index="0" ref="filedict"/>     </bean>           <!-- 构件文件字典类，读取文件字典 。该文件字典包含在jcaptcha-1.0-all.jar 包的toddlist.properties 文件-->     <bean id="filedict" class="com.octo.captcha.component.word.FileDictionary" >        <constructor-arg index="0" value="toddlist"/>     </bean>           <!-- 构件一个从文本到图片的生成类 -->      <bean id="wordtoimage" class="com.octo.captcha.component.image.wordtoimage.ComposedWordToImage" >          <constructor-arg index="0"><ref bean="fontGenRandom"/></constructor-arg>          <constructor-arg index="1"><ref bean="backGenUni"/></constructor-arg>          <constructor-arg index="2"><ref bean="simpleColoredPaster"/></constructor-arg>        </bean>     <!--         构件一个生成随机字体的类 。第一个参数是最小字体大小，第二个参数是最大字体大小，第三个参数是随机的字体列表         这里定义了5种类型的字体     -->     <bean id="fontGenRandom" class="com.octo.captcha.component.image.fontgenerator.RandomFontGenerator" >         <constructor-arg index="0"><value>20</value></constructor-arg>         <constructor-arg index="1"><value>25</value></constructor-arg>         <constructor-arg index="2">                 <list>                    <bean class="java.awt.Font">                        <constructor-arg index="0" value="Arial"/>                        <constructor-arg index="1" value="0"/>                        <constructor-arg index="2" value="10"/>                    </bean>                    <bean class="java.awt.Font" >                        <constructor-arg index="0" value="Tahoma"/>                        <constructor-arg index="1" value="1"/>                        <constructor-arg index="2" value="10"/>                    </bean>                    <bean class="java.awt.Font" >                        <constructor-arg index="0" value="Verdana"/>                        <constructor-arg index="1" value="0"/>                        <constructor-arg index="2" value="10"/>                    </bean>                     <bean class="java.awt.Font" >                        <constructor-arg index="0" value="Comic sans MS"/>                        <constructor-arg index="1" value="0"/>                        <constructor-arg index="2" value="10"/>                    </bean>                     <bean class="java.awt.Font" >                        <constructor-arg index="0" value="Lucida console"/>                        <constructor-arg index="1" value="0"/>                        <constructor-arg index="2" value="10"/>                    </bean>                 </list>         </constructor-arg>     </bean>     <!-- 构件一个背景大小生成类 ，第一个参数是背景宽度，第二个参数是背景高度-->    <bean id="backGenUni" class="com.octo.captcha.component.image.backgroundgenerator.UniColorBackgroundGenerator" >        <constructor-arg index="0"><value>85</value></constructor-arg>        <constructor-arg index="1"><value>40</value></constructor-arg>    </bean>         <!-- 构件一个随机文本个数和颜色，第一个参数是最少文本个数，第二个参数是最多文本个数 -->    <bean id="simpleColoredPaster" class="com.octo.captcha.component.image.textpaster.RandomTextPaster" >        <constructor-arg index="0" value="4"/>        <constructor-arg index="1" value="5"/>        <constructor-arg type="com.octo.captcha.component.image.color.ColorGenerator" index="2" ref="colorGenRandomDark"/>        <constructor-arg index="3" value="true"/>    </bean>    <!-- 构件一个随机的颜色，参数分别代表RGBA通道的取值范围 -->    <bean id="colorGenRandomDark" class="com.octo.captcha.component.image.color.RandomRangeColorGenerator" >            <constructor-arg index="0">                <list>                    <value>0</value>                    <value>255</value>                </list>            </constructor-arg>            <constructor-arg index="1">                <list>                    <value>0</value>                    <value>185</value>                </list>            </constructor-arg>            <constructor-arg index="2">                <list>                    <value>0</value>                    <value>200</value>                </list>            </constructor-arg>            <constructor-arg index="3">                <list>                    <value>255</value>                    <value>255</value>                </list>            </constructor-arg>        </bean> </beans>

各种配置与代码实现是一样的，每个配置中都有注释。

4、  编写一个生成验证码的Servlet，代码如下：

package cn.v5cn.jcaptchatest.spring; import java.awt.image.BufferedImage;import java.io.ByteArrayOutputStream;import java.io.IOException; import javax.imageio.ImageIO;import javax.servlet.ServletException;import javax.servlet.ServletOutputStream;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse; import org.springframework.beans.factory.BeanFactoryUtils;import org.springframework.web.context.WebApplicationContext;import org.springframework.web.context.support.WebApplicationContextUtils; import com.octo.captcha.service.CaptchaServiceException;import com.octo.captcha.service.image.ImageCaptchaService; public class JcaptchaServlet extends HttpServlet {     private static final long serialVersionUID = -8021621053846019170L;    public static final String CAPTCHA_IMAGE_FORMAT = "jpeg";     private ImageCaptchaService captchaService;     @Override    public void init() throws ServletException {        WebApplicationContext appCtx = WebApplicationContextUtils.getWebApplicationContext(getServletContext());                 captchaService = (ImageCaptchaService) BeanFactoryUtils.beanOfTypeIncludingAncestors(appCtx, ImageCaptchaService.class);    }     @Override    protected void doGet(HttpServletRequest request,            HttpServletResponse response) throws ServletException, IOException {        byte[] captchaChallengeAsJpeg = null;                 ByteArrayOutputStream jpegOutputStream = new ByteArrayOutputStream();        try {             String captchaId = request.getSession().getId();            BufferedImage challenge = captchaService.getImageChallengeForID(                    captchaId, request.getLocale());                         ImageIO.write(challenge, CAPTCHA_IMAGE_FORMAT, jpegOutputStream);        } catch (IllegalArgumentException e) {            response.sendError(HttpServletResponse.SC_NOT_FOUND);            return;        } catch (CaptchaServiceException e) {            response.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);            return;        }         captchaChallengeAsJpeg = jpegOutputStream.toByteArray();         // flush it in the response        response.setHeader("Cache-Control", "no-store");        response.setHeader("Pragma", "no-cache");        response.setDateHeader("Expires", 0);        response.setContentType("image/" + CAPTCHA_IMAGE_FORMAT);         ServletOutputStream responseOutputStream = response.getOutputStream();        responseOutputStream.write(captchaChallengeAsJpeg);        responseOutputStream.flush();        responseOutputStream.close();    }}

5、在web.xml中注册这Servlet，代码如下：

<servlet>    <servlet-name>springCaptcha</servlet-name>    <servlet-class>cn.v5cn.jcaptchatest.spring.JcaptchaServlet</servlet-class>  </servlet>  <servlet-mapping>    <servlet-name>springCaptcha</servlet-name>    <url-pattern>/scgvc</url-pattern>  </servlet-mapping>

6、验证步骤与代码实现一样，请大家自行编写。

二、kaptcha验证码使用

个人感觉kaptcha使用比jcaptcha相对简单。

1、在Servelt中配置kaptcha的Servlet，代码如下：

<!-- kaptcha验证码配置 -->  <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.textproducer.font.color</param-name>        <param-value>black</param-value>    </init-param>    <init-param>        <param-name>kaptcha.textproducer.char.space</param-name>        <param-value>5</param-value>    </init-param>  </servlet>     <servlet-mapping>        <servlet-name>kaptcha</servlet-name>        <url-pattern>/kaptcha.jpg</url-pattern>    </servlet-mapping>

kaptcha.border：是否显示边框。

kaptcha.textproducer.font.color：字体颜色

kaptcha.textproducer.char.space：字符间距

更多的属性设置可以在com.google.code.kaptcha.Constants类中找到。其中包括：

kaptcha.border.color：边框颜色

kaptcha.border.thickness：边框宽度

kaptcha.textproducer.char.length：产生字符的长度

kaptcha.textproducer.font.size：产生字符的大小

kaptcha.image.width：产生图片的宽度

kaptcha.image.height：产生图片的高度，等

2、编写一个显示验证码的页面，代码如下：

<form action="kaptcha" method="post">        <input type="text" name="kaptchaValidate">        <img id="vcode" style="vertical-align: middle;" title="点击更换" alt="验证图片" src="kaptcha.jpg" height="40" width="85">        <input type="submit" value="提交">    </form>

3、运行页面显示如下：

4、  编写一个验证的Servelt，代码如下：

package cn.v5cn.kaptcha; 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.google.code.kaptcha.Constants; public class KaptchaValidateServlet extends HttpServlet {     private static final long serialVersionUID = -7642000788132875193L;         @Override    protected void doPost(HttpServletRequest req, HttpServletResponse resp)            throws ServletException, IOException {        String validate = req.getParameter("kaptchaValidate");        String validateCode = (String) req.getSession().getAttribute(Constants.KAPTCHA_SESSION_KEY);                 if(validate==null || validateCode == null){            resp.sendRedirect("fail.html");        }else if(!validateCode.equals(validate)){            resp.sendRedirect("fail.html");        }else{            resp.sendRedirect("success.html");        }    }}

三、总结：

到处jcaptcha和kaptcha的验证代码就编写完成了，写的还比较浅显。希望对需要这两个验证码包的朋友有所帮助，也是给自己一个备忘。