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What is session ?how to manage the session?
jimmy514in
- Jul 4th, 2010
I thought we use session.getAttribute("attr_name") and session.setAttribute("attr_name",obj) to use session management!Do we use getValue and setValue()...??
bhanulee
- Apr 3rd, 2006
Session is an object of method maintaining state which is act of preserving the information from one page to another page. we can manage sessions in two ways using cookies using URL rewriting
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I can do every thing using jsp itself,then what is the need of using servlet?in which situation ,we must use servlet with jsp?
jimmy514in
- Jul 4th, 2010
JSP's are for view.You are normally supposed to just view the O/p using JSP.Servlets are the controller classes,They delegate the requests to the appropriate business logic class (Model) to execut...
Amit Kumar
- Feb 7th, 2006
We cann't implements interface in Jsp but it is in the servlet. Yes, it is true, we can every thing in JSP as in the servlet. But, Jsp is always used for design layout or view whereas the servlet is u...
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Consider a scenario where 2 instances of an appserver are running in a machine. And one application has been deployed in the two servers. Does these two applications deployed in two servers use the same JVM or different?
jimmy514in
- Jul 4th, 2010
Okay, so i have a question , if the 2 web applications are on the same server, Do they run on the the same JVM...but they have their own Servletcontext and their own runtime enviornment..?Just like a sand box?..Please clarify this point.Thanks!
Neeraj
- Aug 19th, 2006
If there are are two AppServer in a physical box, they must have their own JVM. So even if same application deployed on these appServer it will be on different JVM.
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How do to prevent user by viewing secured page by clicking back button when session expired..:)
jimmy514in
- Jul 4th, 2010
Please correct me if I am wrong,how about if we have a session.invalidate() method called during the logout button click.And while going back we can just check request.getSession(false) if the session exists then we can continue working else we have a session expired error!
Arindam
- Nov 10th, 2005
You will need to set the appropriate HTTP header attributes to prevent the dynamic content output by the JSP page from being cached by the browser. Just execute the following scriptlet at the beginnin...
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How Servlet Applet communication achieved?
jimmy514in
- Jul 3rd, 2010
Create a URL. Retrieve the URLConnection object. Set output capability on the URLConnection. Open a connection to the resource. Get an output stream from the connection. Write to the output stream. Close the output stream.
Shaik
- Oct 20th, 2007
Servlet - Applet communication can be achieved in the following way.a) Type the following code in your applet. //The path of the servlet needs to be passed as input param to URL C...
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What is servlet context and what it takes actually as parameters?
">What is servlet context and what it takes actually as parameters?
jimmy514in
- Jul 3rd, 2010
You cannot set the attribute of the servletcontext,You can only call the getAttribute() of the servletContext object.The attribute of the servletContext can be set in the web.xml file using <c...
Aparna
- May 5th, 2006
Sumit Sengar Wrote: Another very important and practical application of ServletContext that i have come across is that it can be used to hold the object which can generate request independent and non-...
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Suppose in web.xml file we are given 30 and in the servlet program we are given setSessionInActiveInterval(40).when that session will be terminated ? After 30 sec or 40 sec?
yogesh249
- Jun 30th, 2010
Session.setMaxInactiveInterval(20*60) Only the session on which you call the method is affected.But if you configure in DD (i.e. web.xml) it changes all the sessions of the web-application.
yogesh249
- Jun 30th, 2010
setMaxInactiveInterval specifies the maximum time, in seconds, that you want to allow between client requests for this session.When configuring in web.xml<web-app>...<session-config> ...
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What is the difference between ServetConfig and ServletContext..?
surikvs332
- Jun 22nd, 2010
ServletConfig: This is mainly to get the configuration parameters int your serlet. With this we can get the configuaration data which we menstioned in the web.xml file.ServletContext: This is fo...
gokulakrishnan
- Sep 28th, 2005
SevletConfig is used to give the information during the initializing period.ServletContext is used for thye communication between the servlet and the servletcontainer thatis to give MIME ty...
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After converting jsp into servlet which methods are present i.e all 6 methods(jspinit(),_jspService(),jspDestroy(),init(),service(),destroy()) or only 3 methods i.e either jsp life cycle methods or servlet lifecycle methods
kotichallenges
- Jun 7th, 2010
We can see _jspInit(), _jspService(), _jspDestroy() available after deploying the JSP file.
Vandana
- Aug 22nd, 2006
A jsp is basically a servlet so, there would be three methods not 6. jspInit() and jspDestroy() mehtods would be visible only if you override them in jsp page<%!public void jspInit() {//initialization code}public void jspInit() {//destroy code}%>_jspService() mehtod is always visible.
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What is the difference between URL and URI?
movie_22
- May 21st, 2010
URL->gives the complete path, including servername, host,path and target resourceURI-> only name of the target resource
atulkumar81
- Apr 23rd, 2007
URL-Uniform Resource Locator & URI-Unifrom Resource Identifier.
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What is difference between sendRedirect() and forward()..? Which one is faster then other and which works on server?
paramsethi
- Apr 8th, 2010
In addition to all of the above answers, one point of difference that was missed is,The forward method takes the relative URL to the servlet, where as sendRedirect method requires the full URL of the destination.
aditya25_abes
- Jun 15th, 2008
forward() can be used only within same application and response is send by the forwarded servlet.while send Redirect can also be be used outside the the application (requested servlet must be deploy o...
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JSP Internal Objects
Name the internal objects of JSP?
amitcsknit
- Dec 30th, 2009
In a more technical way we can say that Implicit object are only local variable which are decalred outside _JspService method and they have std names so that we can use them in our scriptlet as w...
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What is the servlet life cycle?
Each servlet has the same life cycle:A server loads and initializes the servlet (init())The servlet handles zero or more client requests (service())The server removes the servlet (destroy()) (some servers do this step only when they shut down)
Sonikanth
- Feb 22nd, 2010
Servlet Life cycle contains public void init(ServletConfig cg)public void service(HttpServletRequest req, HttpServletResponse res)public void destroy()init() with zero arguments is the helper method for init(-) with one parameter.
Santosh Kumar
- Oct 13th, 2005
Servlet life cycle defines the life process of the servlet. It has certain methods that comes into existence throughout the utilization of the servlet. Generally newInstance() method creates an object...
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What is the need for having HTTPServlet class when we already have GenericServlet class which can handle all type of requests?
satin40
- Apr 20th, 2009
Http servlets is the sub class of Generic servlet so all the life cycle methods available in the generic servlets are available to the Http servlets. Http servlets provides methods that supports cooki...
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What is the difference between ServletContext and ServletConfig?
Both are interfaces. The servlet engine implements the ServletConfig interface in order to pass configuration information to a servlet. The server passes an object that implements the ServletConfig interface to the servlet's init() method.The ServletContext interface provides information to servlets regarding the environment in which they are running. It also provides standard way for servlets to write...
lavanyarani
- Nov 9th, 2009
ServletContext and ServletConfig are the interfaces provided by java class in servlet API.The vendors of web containers(WC) provides the classes implementing these interfaces.It is the responsiblity o...
jawaharl0207
- Oct 22nd, 2009
ServletConfig gives the information about the servlet initialization, it is an interface, where as ServletContext holds the information about whole application(project), the servlet container will create the object of ServletContext. Each servlet has its own ServletConfig object.
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How many Request, Response & session instance you can create for N number of uesr request from a. user request from same userb. user request from diffrent user
Praveen.kb
- Sep 4th, 2009
1 session for 1 user.Multiple request-response objects for multiple request for 1 user.
myogeshchavan97
- Jul 26th, 2009
For each new request one request instance and one response instance is created and for each servlet only one session instance is created.
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What is the main purpose of Servlet? Why it is developed in Java?
Praveen.kb
- Sep 4th, 2009
Web server is not that much intelligent to handle requests where?dynamic data to be inserted. In this case, Web servers need helper classes to accomlish the same. CGI is also widely used like?Servle...
sampra
- Mar 4th, 2008
Servlet Technology is an implementation of the CGI standard, much better than that. It allows you to create dynamic web applications as opposed to the static HTML.
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What is difference between Redirect and request dispatch
Praveen.kb
- Sep 4th, 2009
Request Dispatcher - Dispatch the request to some other JSP or Servlet, user will not aware of this and finally response will go from where the request is dispatched.Request Redirect - Redir...
prasad_posina
- Sep 21st, 2007
Using the redirect method ,we can forward the request to servlet that is either in the same servlet container or in other container .When we are using request dispatch method ,we can forward the request only to a servlet that is in the current container.
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What is the Servlet Interface?
The central abstraction in the Servlet API is the Servlet interface. All servlets implement this interface, either directly or, more commonly, by extending a class that implements it such as HttpServlet.Servlets-->Generic Servlet-->HttpServlet-->MyServlet.The Servlet interface declares, but does not implement, methods that manage the servlet and its communications with clients. Servlet writers...
senthil_2009
- Sep 3rd, 2009
The central abstraction in the Servlet API is the Servlet interface. All servlets implement this interface, either directly or, more
trinadhd
- Jul 7th, 2009
It is nothing but an interface which contains set of method names (prototypes).Those are called servlet life cycle methods.init(ServletConfig)getServletConfig()service(SeveletRequest , ServletResponce...
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Session and Cookie
What is the different between session and cookies? Where is the session information stored? In RAM of the Client or Disk of the Client or it is stored on the server?
vinaymudgil007
- Aug 30th, 2009
well, the purpose of session and cookie is the same --- to maintain the state [in a typical web application, based on http protocol]Session -- Its stored at server side [containers memory, R...
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