In which three directories， relative to a web application’s root， may a tag library descriptor file reside whendeployed directly into a web application？（）

多项选择题Giventhatascopedattributecartexistsonlyinauser’ssession，whichtwo，takenindependently，ensurethescopedattributecartnolongerexists？（）

A.${cart = null}
B.<c：remove var="cart" />
C.<c：remove var="${cart}" />
D.<c：remove var="cart" scope="session" />
E.<c：remove scope="session">cart</c：remove>

多项选择题Given in a single JSP page： <%@ taglib prefix=’java’ uri=’myTags’ %> <%@ taglib prefix=’JAVA’ uri=’moreTags’ %>  Which two are true？（）

A.The prefix ’java’ is reserved.
B.The URI ’myTags’ must be properly mapped to a TLD file by the web container.
C.A translation error occurs because the prefix is considered identical by the web container.
D.For the tag usage ， the tag1 must be unique in the union of tag names in ’myTags’ and’moreTags’.

单项选择题Whichinterfacemustasessionattributeimplementifitneedstobenotifiedwhenawebcontainerpersistsasession？（）

A.javax.servlet.http.HttpSessionListener
B.javax.servlet.http.HttpSessionBindingListener
C.javax.servlet.http.HttpSessionAttributeListener
D.javax.servlet.http.HttpSessionActivationListener

单项选择题A web application uses the HttpSession mechanism to determine if a user is  logged in.  When a usersupplies a valid user name and password， an HttpSession is created for that user. The user has access tothe application for only 15 minutes after logging in. The code must determine how long the user has beenlogged in， and if this time is greater than 15 minutes， must destroy the HttpSession. Which method in HttpSession is used to accomplish this？（）

A.Getcreationtime
B.Invalidateafter
C.Getlastaccessedtime
D.Getmaxinactiveinterval

单项选择题Given an HttpServletRequest request and an HttpServletResponse response： 41.HttpSession session = null； 42.  insert code here 43.if（session == null） { 44.  do something if session does not exist 45.} else { 46.  do something if session exists47. } To implement the design intent，which statement must be inserted at line 42？（）

A.session = response.getSession（）；
B.session = request.getSession（）；
C.session = request.getSession（true）；
D.session = request.getSession（false）；
E.session = request.getSession（"jsessionid"）；