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？（）

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"）；

多项选择题WhichtwostatementsaretrueaboutusingtheisUserInRolemethodtoimplementsecurityinaJavaEEapplication？（）

A.It can be invoked only from the doGet or doPost methods.
B.It can be used independently of the getRemoteUser method.
C.Can return "true" even when its argument is NOT defined as a valid role name in the deployment descriptor.
D.Using the isUserInRole method overrides any declarative authentication related to the method in which it is invoked.

多项选择题Whichtwoarerequiredelementsfortheelementofawebapplicationdeploymentdescriptor？（）

A.<realm-name>
B.<url-pattern>
C.<description>
D.<web-resource-name>
E.<transport-guarantee>

单项选择题Whichelementofawebapplicationdeploymentdescriptorelementisrequired？（）

A.<realm-name>
B.<auth-method>
C.<security-role>
D.<transport-guarantee>
E.<web-resource-collection>

多项选择题Whichtwostatementsaretrueaboutthesecurity-relatedtagsinavalidJavaEEdeploymentdescriptor？（）

A.Every  tag must have at least one  tag.
B.A  tag can have many  tags.
C.A given  tag can apply to only one  tag.
D.A given  tag can contain from zero to many  tags.
E.It is possible to construct a valid  tag such that，for a given resource，no user rolescan access that resource.