A. Access to session-scoped attributes is guaranteed to be thread-safe by the web container.
B. To activate URL rewriting， the developer must use the HttpServletResponse.setURLRewriting method.
C. If the web application uses HTTPS， then the web container may use the data on the HTTPS request stream to identify the client.
D. The JSESSIONID cookie is stored permanently on the client so that a user may return to the web application and the web container will rejoin that session.

A. Tag files can only be accessed using a tagdir attribute.
B. The sort.jsp page translates successfully and invokes the tag defined by beta.tag.
C. The sort.jsp page produces a translation error because a taglib directive must always have a uri attribute.
D. Tag files can only be placed in /WEB-INF/tags， and NOT in any subdirectories of /WEB-INF/tags.
E. The tagdir attribute in line 2 can be replaced by a uri attribute if a TLD referring to beta.tag is created and added to the web application.