尝试使用wso2尝试SAML的travelocity.com，由于此错误而无法显示SAML返回的声明：
HTTP Status 500 – Internal Server Error
Type Exception Report
Message javax.xml.parsers.FactoryConfigurationError: Provider org.apache.xerces.jaxp.DocumentBuilderFactoryImpl not found
Exception
javax.servlet.ServletException: javax.xml.parsers.FactoryConfigurationError: Provider org.apache.xerces.jaxp.DocumentBuilderFactoryImpl not found
Root Cause
javax.xml.parsers.FactoryConfigurationError: Provider org.apache.xerces.jaxp.DocumentBuilderFactoryImpl not found
`
Jar file xercesImpl-2.8.1.jar is in lib folder under travelocity.com application but seems it is not able to read it.
I saw that in the runtime tomcat : HTTP Session created without LoggedInSessionBean and the page getting the 500 error is using this reference: <%@ page import="org.wso2.carbon.identity.sso.agent.bean.LoggedInSessionBean" %>
任何线索为什么要得到这个？