Oracle Oracle Certifications 1Z0-858 Questions & Answers

• Question 71:

  Which two are characteristics of the Intercepting Filter pattern? (Choose two.)

  A. It provides centralized request handling for incoming requests.

  B. It forces resource authentication to be distributed across web components.

  C. It reduces coupling between presentation-tier clients and underlying business services.

  D. It can be added and removed unobtrusively, without requiring changes to existing code.

  E. It allows preprocessing and postprocessing on the incoming requests and outgoing responses.

  Correct Answer: DE

• Question 72:

  A developer has created a web application that includes a servlet for each use case in the application. These servlets have become rather difficult to maintain because the request processing methods have become very large. There is also common processing code in many servlets because these use cases are very similar. Which two design patterns can be used together to refactor and simplify this web application? (Choose two.)

  A. Proxy

  B. View Helper

  C. Front Controller

  D. Session Facade

  E. Business Delegate

  F. Model-View-Controller

  Correct Answer: CF

• Question 73:

  A developer is designing a multi-tier web application and discovers a need to hide the details of establishing and maintaining remote communications from the client. In addition, the application needs to find, in a transparent manner, the heterogeneous business components used to service the client's requests. Which design patterns, working together, address these issues?

  A. Business Delegate and Transfer Object

  B. Business Delegate and Service Locator

  C. Front Controller and Business Delegate

  D. Intercepting Filter and Transfer Object

  E. Model-View-Controller and Intercepting Filter

  Correct Answer: B

• Question 74:

  A developer for the company web site has been told that users may turn off cookie support in their browsers. What must the developer do to ensure that these customers can still use the web application?

  A. The developer must ensure that every URL is properly encoded using the appropriate URL rewriting APIs.

  B. The developer must provide an alternate mechanism for managing sessions and abandon the HttpSession mechanism entirely.

  C. The developer can ignore this issue. Web containers are required to support automatic URL rewriting when cookies are not supported.

  D. The developer must add the string ?id= to the end of every URL to ensure that the conversation with the browser can continue.

  Correct Answer: A

• Question 75:

  You need to store a floating point number, called Tsquare, in the session scope. Which two code snippets allow you to retrieve this value? (Choose two.)

  A. float Tsquare = session.getFloatAttribute("Tsquare");

  B. float Tsquare = (Float) session.getAttribute("Tsquare");

  C. float Tsquare = (float) session.getNumericAttribute("Tsquare");

  D. float Tsquare = ((Float) session.getAttribute.("Tsquare")).floatValue();

  E. float Tsquare = ((Float) session.getFloatAttribute.("Tsquare")).floatValue;

  F. float Tsquare = ((Float) session.getNumericAttribute.("Tsquare")).floatValue;

  Correct Answer: BD

• Question 76:

  Given the definition of MyObject and that an instance of MyObject is bound as a session attribute:

  8.

  package com.example;

  9.

  public class MyObject implements

  10.

  javax.servlet.http.HttpSessionBindingListener {

  11.

  // class body code here

  12.

  }

  Which is true?

  A. Only a single instance of MyObject may exist within a session.

  B. The unbound method of the MyObject instance is called when the session to which it is bound times out.

  C. The com.example.MyObject must be declared as a servlet event listener in the web application deployment descriptor.

  D. The valueUnbound method of the MyObject instance is called when the session to which it is bound times out.

  Correct Answer: D

• Question 77:

  As a convenience feature, your web pages include an Ajax request every five minutes to a special servlet that monitors the age of the user's session. The client-side JavaScript that handles the Ajax callback displays a message on the screen as the session ages. The Ajax call does NOT pass any cookies, but it passes the session ID in a request parameter called sessionID. In addition, assume that your webapp keeps a hashmap of session objects by the ID. Here is a partial implementation of this servlet:

  10.

  public class SessionAgeServlet extends HttpServlet {

  11.

  public void service(HttpServletRequest request, HttpServletResponse) throws IOException {

  12.

  String sessionID = request.getParameter("sessionID");

  13.

  HttpSession session = getSession(sessionID);

  14.

  long age = // your code here

  15.

  response.getWriter().print(age);

  16.

  }

  ... // more code here

  47. }

  Which code snippet on line 14, will determine the age of the session?

  A. session.getMaxInactiveInterval();

  B. session.getLastAccessed().getTime() - session.getCreationTime().getTime();

  C. session.getLastAccessedTime().getTime() - session.getCreationTime().getTime();

  D. session.getLastAccessed() - session.getCreationTime();

  E. session.getMaxInactiveInterval() - session.getCreationTime();

  F. session.getLastAccessedTime() - session.getCreationTime();

  Correct Answer: F

• Question 78:

  One of the use cases in your web application uses many session-scoped attributes. At the end of the use case, you want to clear out this set of attributes from the session object. Assume that this static variable holds this set of attribute names:

  201.

  private static final Set USE_CASE_ATTRS;

  202.

  static {

  203.

  USE_CASE_ATTRS.add("customerOID");

  204.

  USE_CASE_ATTRS.add("custMgrBean");

  205.

  USE_CASE_ATTRS.add("orderOID");

  206.

  USE_CASE_ATTRS.add("orderMgrBean");

  207.

  }

  Which code snippet deletes these attributes from the session object?

  A. session.removeAll(USE_CASE_ATTRS);

  B. for ( String attr : USE_CASE_ATTRS ) {session.remove(attr);}

  C. for ( String attr : USE_CASE_ATTRS ) {session.removeAttribute(attr);}

  D. for ( String attr : USE_CASE_ATTRS ) {session.deleteAttribute(attr);}

  E. session.deleteAllAttributes(USE_CASE_ATTRS);

  Correct Answer: C

• Question 79:

  Given an HttpServletRequest request:

  22.

  String id = request.getParameter("jsessionid");

  23.

  // insert code here

  24.

  String name = (String) session.getAttribute("name");

  Which three can be placed at line 23 to retrieve an existing HttpSession object? (Choose three.)

  A. HttpSession session = request.getSession();

  B. HttpSession session = request.getSession(id);

  C. HttpSession session = request.getSession(true);

  D. HttpSession session = request.getSession(false);

  E. HttpSession session = request.getSession("jsessionid");

  Correct Answer: ACD

• Question 80:

  Given a portion of a valid Java EE web application's directory structure:

  MyApp | |-- Directory1 | |-- File1.html | |-- META-INF | |-- File2.html | |-- WEB-INF |-- File3.html

  You want to know whether File1.html, File2.html, and/or File3.html is protected from direct access by your web client's browsers.

  What statement is true?

  A. All three files are directly accessible.

  B. Only File1.html is directly accessible.

  C. Only File2.html is directly accessible.

  D. Only File3.html is directly accessible.

  E. Only File1.html and File2.html are directly accessible.

  F. Only File1.html and File3.html are directly accessible.

  G. Only File2.html and File3.html are directly accessible.

  Correct Answer: B