Servlet A receives a request that it forwards to servlet B within another web application in the same web container. Servlet A needs to share data with servlet B and that data must not be visible to other servlets in A’s web application.  In which object can the data that A shares with B be stored？（）

多项选择题Forwhichthreeeventscanwebapplicationeventlistenersberegistered？（）

A. when a session is created
B. after a servlet is destroyed
C. when a session has timed out
D. when a cookie has been created
E. when a servlet has forwarded a request
F. when a session attribute value is changed

多项选择题AdeveloperchoosestoavoidusingSingleThreadModelbutwantstoensurethatdataisupdatedinathread-safemanner.Whichtwocansupportthisdesigngoal？（）

A. Store the data in a vocal variable.
B. Store the data in an instance variable.
C. Store the data in the HttpSession object.
D. Store the data in the ServletContext object.
E. Store the data in the ServletRequest object.

多项选择题ARequestDispatchercanbeobtainedfromwhichtwoobjects？（）

A. ServletConfig
B. ServletContext
C. HttpServletRequest
D. HttpServletResponse

多项选择题Inwhichtwolocationscanlibrarydependenciesbedefinedforawebapplication？（）

A. the web application deployment descriptor
B. the /META-INF/dependencies.xml file
C. the /META-INF/MANIFEST.MF manifest file
D. the /META-INF/MANIFEST.MF manifest of a JAR in the web application classpath

单项选择题Which defines the welcome files in a web application deployment descriptor？（）

A.A
B.B
C.C
D.D
E.E