cas添加验证码,折腾了很久,终于整理好了,很大部分都是借鉴http://binghejinjun.iteye.com/blog/1255293这个的。可是他的有一个很很差的地方就是不能提高验证码错误!css
红色字体的为我添加的,能够提示验证码错误!很简单,感谢。原做者。谢谢。html
1. 首先,我用的cas版本是3.4.6,验证码采用的是CAPTCHA,所需jar包能够google搜索,部署好cas后.在web-info目录下找到login-webflow.xml,打开,找到以下代码: java
<view-state id= "viewLoginForm" view= "casLoginView" model= "credentials" > web <var name= "credentials" class = "org.jasig.cas.authentication.principal.UsernamePasswordCredentials" /> spring <binder> express <binding property= "username" /> session <binding property= "password" /> app </binder> jsp <on-entry> 字体 <set name= "viewScope.commandName" value= "'credentials'" /> </on-entry> <transition on= "submit" bind= "true" validate= "true" to= "realSubmit" > <set name= "flowScope.credentials" value= "credentials" /> <evaluate expression= "authenticationViaFormAction.doBind(flowRequestContext, flowScope.credentials)" /> </transition> </view-state> |
此段代码的功能是绑定cas登陆过程当中的用户名和密码,再次咱们修改以下:
<view-state id= "viewLoginForm" view= "casLoginView" model= "credentials" > <var name= "credentials" class = "org.jasig.cas.authentication.principal.UsernamePasswordCredentials" /> <binder> <binding property= "username" /> <binding property= "password" /> </binder> <on-entry> <set name= "viewScope.commandName" value= "'credentials'" /> </on-entry> <transition on= "submit" bind= "true" validate= "true" to= "yzmSubmit" > <set name= "flowScope.credentials" value= "credentials" /> <evaluate expression= "authenticationViaFormAction.doBind(flowRequestContext, flowScope.credentials)" /> </transition> </view-state> |
也就是说,只须要修改realSubmit为yzmSubmit便可.而后加入以下配置:

<!--fan add start-->
<action-state id="yzmSubmit">
<evaluate expression="yzmViaFormAction.submit(flowRequestContext,messageContext)" />
<transition on="success" to="realSubmit" />
<transition on="error" to="viewLoginForm" />
</action-state>
<!--fan add end-->

此段配置是自定义的验证码验证器,用来验证你提交的验证码的正确性.
2.在web-info下找到cas-servlet.xml,打开后,加入
<!--fan add start--> <bean id= "yzmViaFormAction" class = "com.ivan.zhang.servlet.YzmAction" /> |
<!--fan add end-->此配置是注册自定义的验证码
3.编写以下类:
package com.ivan.zhang.servlet; import com.ivan.zhang.CaptchaServiceSingleton; import com.octo.captcha.service.image.ImageCaptchaService; import java.io.PrintStream; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpSession; import org.jasig.cas.web.support.WebUtils; import org.springframework.webflow.core.collection.ParameterMap; import org.springframework.webflow.execution.RequestContext; public class YzmAction { public final String submit(RequestContext context) throws Exception { Boolean flag = Boolean.valueOf( false ); System.out.println( "YzmAction is submiting...................." ); String yzm = context.getRequestParameters().get( "yzm" ); String captchaId = WebUtils.getHttpServletRequest(context).getSession().getId(); flag = CaptchaServiceSingleton.getInstance().validateResponseForID(captchaId, yzm); if (flag.booleanValue()) { return "success" ; } <br> //<span style="background-color: #ff0000;">我添加的改动。提示验证码错误</span> |
MessageBuilder msgBuilder = new MessageBuilder();
msgBuilder.defaultText("验证码错误!");
messageContext.addMessage(msgBuilder.error().build());
其中,flag = CaptchaServiceSingleton.getInstance().validateResponseForID(captchaId,
yzm);
此句话是为了验证提交的验证码和先前生成的验证码的正确性,以此做为验证结果跳转的依据.CaptchaServiceSingleton此类是自定义类,稍后会附加完整的类供下载调试.
4.打开web-info/view/jsp/default/ui/casLoginView.jsp,在密码下面加入
<%--fan add start --%> <img alt= "yzm" src= "captcha.jpg" > <spring:message code= "screen.welcome.label.yzm.accesskey" var= "yzmAccessKey" /> <form:input cssClass= "required" cssErrorClass= "error" id= "yzm" size= "25" tabindex= "1" accesskey= "${yzmAccessKey}" path= "yzm" autocomplete= "false" htmlEscape= "true" /> <%--fan add end --%> |
5. 最后一步则是注册验证码生成器,打开web.xml文件,加入
<servlet> <servlet-name>jcaptcha</servlet-name> <servlet- class >com.ivan.zhang.servlet.ImageCaptchaServlet</servlet- class > <load-on-startup> 0 </load-on-startup> </servlet> <servlet-mapping> <servlet-name>jcaptcha</servlet-name> <url-pattern>/captcha.jpg</url-pattern> </servlet-mapping> |
ok,就这么简单.简单解释一下流程,web.xml中注册的类是用来调用自定义的验证码生成器,以便在显示登录界面的时候绘制验证码图片,并在session中生成标志位并记录,当用户提交验证码和用户名密码时,会先走自定义的验证码验证器(此时会先验证验证码的正确性),若是正确,再走用户名和密码的验证,若是不正确,则直接跳转回登录页面.yzm.jar是自定义的验证码生成器和验证类,直接打包好后放到web-info/lib下.
努力生活,珍惜一切,满足最快乐!young joy..