cas错误:org.jasig.cas.client.validation.TicketValidationException: No principal was found in the response from the CAS server.

根据网上所说，是在第5步： Step 5: CAS客户端取出ticket，生成“ticket验证URL”,然后向"ticket验证URL"发起http GET请求 "ticket验证URL":    http://${cas-server-host}:${cas-server-port}/cas-server /serviceValidate?ticket=${service-ticket}&service=${client-service-url} 出的错，然后我把ticket取出，单独放到这个url里面去，页面提示：

大虾们知道的教教小弟。

猜测是证书引起的。 可以试试不用证书的时候是否正常。我记得以前本机测试的时候没用证书都正常， 用了证书就有类似的错误。

记不清了

终于解决了，这个错误怎么就没人发现呢，哎。最后还是看：http://jasig.275507.n4.nabble.com/No-principal-was-found-in-the-response-from-the-CAS-server-td1011262.html找到的方法，现把原因贴出来：

cas客户的的web.xml文件：

您好，我也碰到了相同的问题，但是按照你的解决方法，我还是会出错。错误信息如下：

java.lang.RuntimeException: java.io.IOException: Server returned HTTP response code: 500 for URL: http://service.thldl.org.cn/serviceValidate?ticket=ST-6-E5Z7zvVeRd0tvwwewRWw-cas01.example.org&service=http%3A%2F%2Fapp.thldl.org.cn%2F%2F%2Fsigns%2F
	org.jasig.cas.client.util.CommonUtils.getResponseFromServer(CommonUtils.java:328)
	org.jasig.cas.client.util.CommonUtils.getResponseFromServer(CommonUtils.java:291)
	org.jasig.cas.client.validation.AbstractCasProtocolUrlBasedTicketValidator.retrieveResponseFromServer(AbstractCasProtocolUrlBasedTicketValidator.java:32)
	org.jasig.cas.client.validation.AbstractUrlBasedTicketValidator.validate(AbstractUrlBasedTicketValidator.java:187)
	org.jasig.cas.client.validation.AbstractTicketValidationFilter.doFilter(AbstractTicketValidationFilter.java:164)
	org.jasig.cas.client.authentication.AuthenticationFilter.doFilter(AuthenticationFilter.java:102)
	org.jasig.cas.client.session.SingleSignOutFilter.doFilter(SingleSignOutFilter.java:65)

http://service.thldl.org.cn/serviceValidate?ticket