23 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 Java SE's lang.util.prefs package APIs and you have been ordered to reuse this subsystem in your web application. You need to create an event listener that stores the user's Preference object when an HTTP session is created. Also, note that user identification information is stored in an HTTP cookie. Which partial listener class can accomplish this goal? 
(A) Option A
(B) Option B
(C) Option C
(D) Option D

複選題19 A developer chooses to avoid using singieThreadModel but wants to ensure that data If; updated in a thread safe manner. Which two can support this design goal? (Choose two) (A) Store the data in a local variable. (B) Store the data in an instance variable. (C) Store the data in the Httpsession object. (D) Store the data in the sarvletContext object. (E) Store the data in the ServletRequest object.

20 View the exhibit.  Assuming the tag library in the exhibit is imported with the prefix stock, which custom tag Invocation outputs the contents of the variable exposed by the quote tag? (A) ${var}＜stock:quote symbol= "SUNW" /＞ (B) ＜stock:quote symbol= "SUNW"＞$ {var}＜/stock:quote＞ (C) ＜stock:quote symbol= "SUNW" var= "quote" /＞$ {quote} (D) ＜stock:quote symbol= "SUNW" var= "quote"＞＜%= quote %＞＜/stock:quote＞

21 Which Java expression can be used to check whether the web container is currently configured to track sessions via URL rewriting? (A) servletContext.getSessionCookiesConfiq() .isHttpOnly() (B) servletContext.getSessionCookiesConfiq() .isSecure() (C) servletContext.getDefaultSessionTrackingModes() .contains(SessionTrackingMode.URL) (D) servletContext.getEffectiveSessionTrackingModes() .contains (SessionTrackingMode.URL)

22 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 exists  47. } 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");

複選題24 Which two are true about the JSTL core iteration custom tags? (Choose two.) (A) It may iterate over arrays, collections, maps, and strings. (B) The body of the tag may contain EL code, but not scripting code. (C) When looping over collections, a loop status object may be used in the tag body. (D) It may iterate over map, but only the key of the mapping may be used in the tag body. (E) When looping over integers (for example begin= '1' end= '10'), a loop status object may not be used in the tag body.

25 ServletContextListeners are invoked in (A) Random order (B) contextInitialized and contextDestroyed are invoked in the order in which they are declared in the web.xml (C) contextInitialized method are invoked in the order in which they are declared in the web.xml and the contextDestroyed method is invoked in the reverse order in which they are declared in the web.xml (D) contextInitialized and contextDestroyed are invoked in the reverse order of which they are declared in the web.xml

26 Given the web application deployment descriptor elements: Which element, inserted at line 27, causes the ParamAdder filter to be applied when MyServlet is IT Certification Guaranteed, The Easy Way! invoked by another servlet using the RequestDispatcher.include method? (A) ＜include/＞ (B) ＜dispatcher＞INCLUDE＜/dispatcher＞ (C) ＜dispatcher＞include＜/dispatcher＞ (D) ＜filter-condition＞INCLUDE＜/filter-condition＞ (E) ＜filter-condition＞include＜/filter-condition＞

27 Given the java code snippet in contextInitialized method of a ServletContextListner: ServletRegistration.Dynamic sr = (ServletRegistration.Dynamic)sc.addServlet ("myServlet", myServletClass); sr.addMapping("/abc"); sr.setServletSecurityElement(servletSecurityElement); sr.addMapping("/def"); Which statement is true? (A) "/abc" is mapped to "myservlet". The servletSecurityElementy applies to both "/abc" and "/def". (B) Both "/abc" and "/def" are mapped to "myservlet". The servletSecurityElementy applies to "/abc". (C) Both "/abc" and "/def" are mapped to "myservlet". The servletSecurityElementy applies to "/def". (D) Both "/abc" and "/def" are mapped to "myservlet". The servletSecurityElementy applies to both "/abc" and "/def". (E) Both "/abc" and "/def" are mapped to "myservlet". The servletSecurityElementy applies to "/abc", but the behavior for "/def" is not specified.

28 An application stores session data in a JavaBean object. The object is then stored in the HttpSession object. Which is true? (A) Synchronization of all bean methods is required to ensure thread safety. (B) Thread safety is not an issue, since concurrent access to a single session is impossible. (C) Appropriate protection against problems caused by concurrent access should be provided by the bean. (D) The servlet should take precautions to ensure that concurrent access to the bean is prevented. (E) The servlet should implement SingleThreadModel

29 Given a war file with the following structure | - WEB-INF/classes/Myservlet.class | - WEB-INF/lib/wf.jaf Where wf.jar contains a valid web-fragment.xml and the following two classes: MyFilter1.class and MyFiler2.class. The web-fragment.xml is as follows: The following are some code snippets: When one access "/" of the above web application, which filters will be executed? (A) No filters will be executed. (B) MyFilter1 (C) MyFilter2 (D) MyFilter1 and MyFilter2