code: public Object getService(RequestWrapper request) {
  		ContainerWrapper cw = containerCallback.getContainerWrapper();
  		SessionContextSetup sessionContextSetup = (SessionContextSetup) cw.lookup(ComponentKeys.SESSIONCONTEXT_SETUP);
  
  		TargetMetaRequest targetMetaRequest = targetMetaRequestsHolder.getTargetMetaRequest();
  		targetMetaRequest.setVisitableName(ComponentKeys.SESSIONCONTEXT_FACTORY);
  		ComponentVisitor componentVisitor = targetMetaRequest.getComponentVisitor();
  		SessionContext sessionContext = (SessionContext) componentVisitor.createSessionContext();
  
  		targetMetaRequest.setSessionContext(sessionContext);
  		sessionContextSetup.setup(sessionContext, request);
  		return serviceAccessor.getService();
  	}
docs: /*
  1. create a SessionContext object in httpsession 2. save the principle
  name in the session context.
  
  the principle name the request.getPrincipleNme you can save more
  attribute in the SessionContext object by replcaing this class in
  container.xml
  
  SessionContextInterceptor will get the SessionContext into targetObject
  implements SessionAcceptable