jcaptcha配置验证码

准备开始

首先导入jar包：jcaptcha-my-1.0

/**

* web 常量

* @author lx

public abstract class Constants {

/** 用户 session 的 cookie 名称*/

public static final String SESSION_ID = "JSESSIONID";

}

第一步:创建SessionProvider接口

cn.itcast.common.web.session.SessionProvider

public interface SessionProvider {

public void setAttribute(HttpServletRequest request,String name ,Serializable value);

//获取Session中的值

public Serializable getAttribute(HttpServletRequest request,String name);

//退出登陆

public void logout(HttpServletRequest request,HttpServletResponse response);

//获取Session Id

public String getSessionId(HttpServletRequest request);

}

第二步:创建HttpSessionProvider实现类

cn.itcast.common.web.session.HttpSessionProvider

/**

* Session提供类

* @author lx

public class HttpSessionProvider implements SessionProvider{

//往Session中设置值

public void setAttribute(HttpServletRequest request,String name ,Serializable value){

HttpSession session = request.getSession();

if(session != null){

session.setAttribute(name, value);

}

//获取Session中的值

public Serializable getAttribute(HttpServletRequest request,String name){

HttpSession session = request.getSession(false);

if(session != null){

return (Serializable) session.getAttribute(name);

}else{

return null;

}

//退出登陆

public void logout(HttpServletRequest request,HttpServletResponse response){

HttpSession session = request.getSession(false);

if(session != null){

session.invalidate();

}

Cookie c = new Cookie(Constants.SESSION_ID,null);

c.setMaxAge(0);

response.addCookie(c);

}

//获取Session Id

public String getSessionId(HttpServletRequest request){

return request.getRequestedSessionId();

}

第三步:创建classpath:config/utils.xml

第四步:创建JcaptchaServlet

第五步:创建classpth:config/captcha.xml

<?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-3.0.xsd"

default-lazy-init="true">

<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>

<constructor-arg index="0">

<list>

</list>

</constructor-arg>

</bean>

<constructor-arg>

</constructor-arg>

<constructor-arg>

</constructor-arg>

</bean>

<constructor-arg>

<value>aabbccddeefgghhkkmnnooppqqsstuuvvwxxyyzz</value>

</constructor-arg>

</bean>

<constructor-arg index="0">

</constructor-arg>

<constructor-arg index="1">

</constructor-arg>

<constructor-arg index="2">

</constructor-arg>

</bean>

<constructor-arg index="0">

</constructor-arg>

<constructor-arg index="1">

</constructor-arg>

<constructor-arg index="2">

<list>

<constructor-arg index="0"><value>Arial</value></constructor-arg>

<constructor-arg index="1"><value>0</value></constructor-arg>

<constructor-arg index="2"><value>32</value></constructor-arg>

</bean>

</list>

</constructor-arg>

</bean>

<constructor-arg index="0">

</constructor-arg>

<constructor-arg index="1">

</constructor-arg>

</bean>

<constructor-arg type="java.lang.Integer" index="0">

</constructor-arg>

<constructor-arg type="java.lang.Integer" index="1">

</constructor-arg>

<constructor-arg index="2">

</constructor-arg>

<constructor-arg index="3">

<list>

</list>

</constructor-arg>

</bean>

<constructor-arg type="java.lang.Integer" index="0"><value>1</value></constructor-arg>

<constructor-arg type="java.awt.Color" index="1"><ref bean="colorWrite"/></constructor-arg>

</bean>

<constructor-arg type="java.awt.Color" index="0">

</constructor-arg>

</bean>

<constructor-arg type="int" index="0">

</constructor-arg>

<constructor-arg type="int" index="1">

</constructor-arg>

<constructor-arg type="int" index="2">

</constructor-arg>

</bean>

<constructor-arg type="int" index="0">

</constructor-arg>

<constructor-arg type="int" index="1">

</constructor-arg>

<constructor-arg type="int" index="2">

</constructor-arg>

</bean>

</beans>

第六步:编写JcaptchaServlet

/**

* 提供验证码图片的Servlet

@SuppressWarnings("serial")

public class JcaptchaServlet extends HttpServlet {

public static final String CAPTCHA_IMAGE_FORMAT = "jpeg";

private ImageCaptchaService captchaService;

private SessionProvider session;

@Override

public void init() throws ServletException {

WebApplicationContext appCtx = WebApplicationContextUtils

.getWebApplicationContext(getServletContext());

captchaService = (ImageCaptchaService) BeanFactoryUtils

.beanOfTypeIncludingAncestors(appCtx, ImageCaptchaService.class);

session = (SessionProvider) BeanFactoryUtils

.beanOfTypeIncludingAncestors(appCtx, SessionProvider.class);

}

@Override

protected void doGet(HttpServletRequest request,

HttpServletResponse response) throws ServletException, IOException {

byte[] captchaChallengeAsJpeg = null;

// the output stream to render the captcha image as jpeg into

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());

// Jimi.putImage("image/jpeg", challenge, jpegOutputStream);

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;

}

// catch (JimiException 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();

}

第七步:配置web.xml

<servlet-name>jcaptcha</servlet-name>

<servlet-class>cn.itcast.common.captcha.JcaptchaServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>jcaptcha</servlet-name>

<url-pattern>/captcha.svl</url-pattern>

</servlet-mapping>

第八步:编写登陆页面front_page/buyer/login.jsp

<li>

</span>

</li>