Spring+JCaptcha验证码使用示例

Spring+JCaptcha验证码使⽤⽰例1，导⼊jcaptcha.jar包，这⾥⽤的是1.0版本
2，编写captcha-context.xml配置⽂件（⾮必须，可在spring配置⽂件中直接添加）：
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="/schema/beans"
xmlns:xsi="/2001/XMLSchema-instance"
xsi:schemaLocation="/schema/beans
/schema/beans/spring-beans.xsd">
<bean id="captchaService" class="com.octo.captcha.service.multitype.GenericManageableCaptchaService">
<constructor-arg index="0" ref="imageEngine"/>
<constructor-arg type="int" index="1" value="180"/>
<constructor-arg type="int" index="2" value="100000"/>
<constructor-arg type="int" index="3" value="75000"/>
</bean>
<bean id="imageEngine" class="com.octo.captcha.engine.GenericCaptchaEngine">
<constructor-arg index="0">
<list>
<ref bean="captchaFactory"/>
</list>
</constructor-arg>
</bean>
<bean id="captchaFactory" class="com.octo.captcha.image.gimpy.GimpyFactory">
<constructor-arg>
<ref bean="wordgen"/>
</constructor-arg>
<constructor-arg>
<ref bean="wordtoimage"/>
</constructor-arg>
</bean>
<bean id="wordgen" class= "ponent.word.wordgenerator.RandomWordGenerator">
<!--可选字符-->
<constructor-arg>
<value>0123456789</value>
<!-- <value>abcdefghijklmnopquvwxyz</value> -->
</constructor-arg>
</bean>
<bean id="wordtoimage" class="posedWordToImage">
<constructor-arg index="0">
<ref bean="fontGenRandom"/>
</constructor-arg>
<constructor-arg index="1">
<ref bean="backGenUni"/>
</constructor-arg>
<constructor-arg index="2">
<ref bean="decoratedPaster"/>
</constructor-arg>
</bean>
<bean id="fontGenRandom" class="ponent.image.fontgenerator.RandomFontGenerator">
<!--最⼩字体-->
<constructor-arg index="0">
<value>16</value>
</constructor-arg>
<!--最⼤字体-->
<constructor-arg index="1">
<value>20</value>
</constructor-arg>
<constructor-arg index="2">
<list>
<bean class="java.awt.Font">
<constructor-arg index="0"><value>Arial</value></constructor-arg>
<constructor-arg index="1"><value>0</value></constructor-arg>
<constructor-arg index="2"><value>12</value></constructor-arg>
</bean>
</list>
</constructor-arg>
</bean>
<bean id="backGenUni" class="ponent.image.backgroundgenerator.FunkyBackgroundGenerator">
<!--背景宽度-->
<constructor-arg index="0">
<value>90</value>
</constructor-arg>
<!--背景⾼度-->
<constructor-arg index="1">
<value>30</value>
</constructor-arg>
</bean>
<bean id="decoratedPaster" class="ponent.image.textpaster.DecoratedRandomTextPaster"> <!--最⼤字符长度-->
<constructor-arg type="ng.Integer" index="0">
<value>4</value>
</constructor-arg>
<!--最⼩字符长度-->
<constructor-arg type="ng.Integer" index="1">
<value>4</value>
</constructor-arg>
<!--⽂本颜⾊-->
<constructor-arg index="2">
<ref bean="colorGen"/>
</constructor-arg>
<!--⽂本混淆-->
<constructor-arg index="3">
<list>
<ref bean="baffleDecorator"/>
</list>
</constructor-arg>
</bean>
<bean id="baffleDecorator" class="ponent.image.textpaster.textdecorator.BaffleTextDecorator"> <constructor-arg type="ng.Integer" index="0"><value>1</value></constructor-arg>
<constructor-arg type="java.awt.Color" index="1"><ref bean="colorWrite"/></constructor-arg>
</bean>
<bean id="colorGen" class="ponent.image.color.SingleColorGenerator">
<constructor-arg type="java.awt.Color" index="0">
<ref bean="colorBlack"/>
</constructor-arg>
</bean>
<bean id="colorWrite" class="java.awt.Color">
<constructor-arg type="int" index="0">
<value>255</value>
</constructor-arg>
<constructor-arg type="int" index="1">
<value>255</value>
</constructor-arg>
<constructor-arg type="int" index="2">
<value>255</value>
</constructor-arg>
</bean>
<bean id="colorBlack" class="java.awt.Color">
<constructor-arg type="int" index="0">
<value>50</value>
</constructor-arg>
<constructor-arg type="int" index="1">
<value>50</value>
</constructor-arg>
<constructor-arg type="int" index="2">
<value>50</value>
</constructor-arg>
</bean>
</beans>
View Code
3，编写JcaptchaServlet响应请求提供验证码输出:
protected void doGet(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
byte[] captchaChallengeAsJpeg = null;
// 输出jpg的字节流
ByteArrayOutputStream jpegOutputStream = new ByteArrayOutputStream();
try {
// get the session id that will identify the generated captcha.
// the same id must be used to validate the response, the session id
// is a good candidate!
String captchaId = session.getSessionId(request);
BufferedImage challenge = captchaService.getImageChallengeForID(
captchaId, request.getLocale());
// a jpeg encoder
JPEGImageEncoder jpegEncoder = JPEGCodec
.createJPEGEncoder(jpegOutputStream);
jpegEncoder.encode(challenge);
} 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();
}
4，在web.xml中添加该servlet：
<!-- Jcaptcha -->
<servlet>
<servlet-name>Jcaptcha</servlet-name>
<servlet-class>cn.xxx.JcaptchaServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>Jcaptcha</servlet-name>
<url-pattern>/captcha.jpg</url-pattern>
</servlet-mapping>
5，在html中显⽰验证码只需要以下代码：
<div><img src="${base }/captcha.jpg" onclick="this.src='${base}/captcha.jpg?'+Math.random()"/></div> <div class="input_capt">验证码: <input type="text"id="captcha" name="captcha" />
6，后台验证的话，只需要调⽤ImageCaptchaService的⼀个⽅法即可：imageCaptchaService.validateResponseForID(session.getSessionId(getRequest()), captcha);。