How do you prevent the Creation of a Session in a JSP Page and why? What is the difference between include directive & jsp:include action?

JSP Interview Questions and Answers

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44. How do you prevent the Creation of a Session in a JSP Page and why? What is the difference between include directive & jsp:include action?

By default, a JSP page will automatically create a session for the request if one does not exist.
However, sessions consume resources and if it is not necessary to maintain a session, one should not be created. For example, a marketing campaign may suggest the reader visit a web page for more information. If it is anticipated that a lot of traffic will hit that page, you may want to optimize the load on the machine by not creating useless sessions.

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Other Interview Questions

• What is a JSP and what is it used for?
• What is difference between custom JSP tags and beans?
• What are the two kinds of comments in JSP and what's the difference between them.
• What is JSP technology?
• What is JSP page?
• What are the implicit objects?
• How many JSP scripting elements and what are they?
• Why are JSP pages the preferred API for creating a web-based client program?
• Is JSP technology extensible?
• Can we use the constructor, instead of init(), to initialize servlet?
• How can a servlet refresh automatically if some new data has entered the database?
• The code in a finally clause will never fail to execute, right?
• How many messaging models do JMS provide for and what are they?
• What information is needed to create a TCP Socket?
• What Class.forName will do while loading drivers?
• How to Retrieve Warnings?
• How many JSP scripting elements are there and what are they?
• In the Servlet 2.4 specification SingleThreadModel has been deprecated, why?
• What are stored procedures? How is it useful?
• How do I include static files within a JSP page?
• Why does JComponent have add() and remove() methods but Component does not?
• How can I enable session tracking for JSP pages if the browser has disabled cookies?
• How do I prevent the output of my JSP or Servlet pages from being cached by the browser?
• How do you restrict page errors display in the JSP page?
• What JSP lifecycle methods can I override?
• How do I perform browser redirection from a JSP page?
• How does JSP handle run-time exceptions?
• How do I use comments within a JSP page?
• Is it possible to share an HttpSession between a JSP and EJB? What happens when I change a value in the HttpSession from inside an EJB?
• How can I implement a thread-safe JSP page?
• How can I declare methods within my JSP page?
• Can I stop JSP execution while in the midst of processing a request?
• Can a JSP page process HTML FORM data?
• Is there a way to reference the "this" variable within a JSP page?
• How do you pass control from one JSP page to another?
• Is there a way I can set the inactivity lease period on a per-session basis?
• How does a servlet communicate with a JSP page?
• How do I include static files within a JSP page?
• Can you make use of a ServletOutputStream object from within a JSP page?
• Can a JSP page instantiate a serialized bean?
• What is JSP?
• How do I mix JSP and SSI #include?
• How do I mix JSP and SSI #include? What is the difference between include directive & jsp:include action?
• How do you prevent the Creation of a Session in a JSP Page and why? What is the difference between include directive & jsp:include action?
• How do I use a scriptlet to initialize a newly instantiated bean?
• How can I set a cookie and delete a cookie from within a JSP page?
• How do you connect to the database from JSP?
• What is the page directive is used to prevent a JSP page from automatically creating a session?
• How do you delete a Cookie within a JSP?
• Can we implement an interface in a JSP?
• What is the difference between ServletContext and PageContext?
• What is the difference in using request.getRequestDispatcher() and context.getRequestDispatcher()?
• How to pass information from JSP to included JSP?
• How is JSP include directive different from JSP include action.
• Can we override the jspInit(), _jspService() and jspDestroy() methods?
• Why is _jspService() method starting with an '_' while other life cycle methods do not?
• Explain the life cycle of JSP?
• What happens when a page is statically included in another JSP page?
• A JSP page, include.jsp, has a instance variable "int a", now this page is statically included in another JSP page, index.jsp, which has a instance variable "int a" declared. What happens when the index.jsp page is requested by the client?
• Can you override jspInit() method? If yes, In which cases?
• What is the difference between directive include and jsp include?
• What is the difference between RequestDispatcher and sendRedirect?
• How does JSP handle runtime exceptions?
• How can my application get to know when a HttpSession is removed?