多项选择题
A.Your filter class must implement an init method and a destroy method.
B.Your filter class must also implement javax.servlet.FilterChain.
C.When your filter chains to the next filter， it should pass the same arguments it received in its doFiltermethod.
D.The method that your filter invokes on the object it received that implements javax.servlet.FilterChaincan invoke either another filter or a servlet.
E.Your filter class must implement a doFilter method that takes， among other things， anHTTPServletRequest object and an HTTPServletResponse object.
多项选择题 A developer wants a web application to be notified when the application is about to be shut down. Which two actions are necessary to accomplish this goal？（）
单项选择题 Your web site has many user-customizable features， for example font and color preferences on web pages.Your IT department has already built a subsystem for user preferences using the Java SE platform’s lang.util.prefs package APIs， and you have been ordered to reuse this subsystem in your web application. Youneed to create an event listener that constructs the preferences factory and stores it in the applicationscope for later use. Furthermore， this factory requires that the URL to a database must be declared in thedeployment descriptor like this： 42. 43.prefsDbURL 44. 45.jdbc：pointbase：server：//dbhost：4747/prefsDB 46. 47. Which partial listener class will accomplish this goal？（）
单项选择题 Servlet A receives a request that it forwards to servlet B within another web application in the same webcontainer. Servlet A needs to share data with servlet B and that data must not be visible to other servlets inA’s web application. In which object can the data that A shares with B be stored？（）