<!-- 该过滤器负责对Ticket的校验工作，必须启用它 --> 

<filter>
<filter-name>CAS Validation Filter</filter-name>
<filter-class>org.jasig.cas.client.validation.Cas20ProxyReceivingTicketValidationFilter</filter-class>
<init-param>
<param-name>casServerUrlPrefix</param-name>
<param-value>http://localhost:8082/cas/</param-value><!-- cas 服务器地址 http://IP:PORT/CasWebProName -->
</init-param>
<init-param>
<param-name>serverName</param-name>
<param-value>http://localhost:8008/</param-value><!-- 客户端服务器地址 http://IP:PORT -->
</init-param>
</filter>
<filter-mapping>
<filter-name>CAS Validation Filter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
本人用的client版本为3.3.2
这个是客户端web.xml中的配置
客户端启动报错：
java.lang.IllegalArgumentException: casServerUrlPrefix cannot be null.
at org.jasig.cas.client.util.CommonUtils.assertNotNull(CommonUtils.java:80)
at org.jasig.cas.client.session.SingleSignOutHandler.init(SingleSignOutHandler.java:142)
at org.jasig.cas.client.session.SingleSignOutFilter.init(SingleSignOutFilter.java:58)
at org.apache.catalina.core.ApplicationFilterConfig.initFilter(ApplicationFilterConfig.java:279)
at org.apache.catalina.core.ApplicationFilterConfig.getFilter(ApplicationFilterConfig.java:260)
at org.apache.catalina.core.ApplicationFilterConfig.<init>(ApplicationFilterConfig.java:105)
at org.apache.catalina.core.StandardContext.filterStart(StandardContext.java:4830)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5510)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1575)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1565)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303)
at java.util.concurrent.FutureTask.run(FutureTask.java:138)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:662)
这是cas服务端请求路径：http://localhost:8082/cas/ 是可以访问的。