JSP Interview Questions

Jsp container provides a easy way to access standard objects and actions..

Easily saying

1)Auto compilation(translation.....)

2)Not deployment descritpor specific

3)Multiple deployment is avoided.

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HTML Comments - The Container passes these comments straight on to the client, where the browser interprets them as HTML comments. The commented out blocks still display in the source code. JSP Comme...

init() and destroy() methods can be override. not service() method.

init() and destroy() methods can be override. not service() method.

absolute url is full url relative url is part of url wn we are in app

As there seems to still be confusion about the difference between relative and absolute urls, I thought I'd post a little information and a reference link for everyone. An url that is ABSOLUTE shows ...

isELIgnored="true"

We can use isEliIgnored property or we can disable by using below code..

isErrorPage and errorPage

Example:


The exception will be thrown inside the catch:

<% int x = 5/0;%>



The exception is : ${catchException}


There is an exception: ${catchException.message}

we can do same as doing in java wd scriptlet

We can call stored producedure using sql tags in jstl "java5 For example, calling a stored procedure that returns a result set: exec ExampleProcLoadExample ? ...

we can set attribute in application session or request attribute.here page wont be use ful bcz scope of page is same page only

1.page
2.session
3.request.
4.application

using these scoped variables we can translate data from one resource to another

ex: request.setAttribute("key","value");
Object o=getAttribute("key");

The RequestDispatcher objects forward method to pass the control. The response.sendRedirect method

Code
<%      response.sendRedirect("RedirectIfSuccessful.html");            %>
 
<%
String st=request.getParameter("n");
if(st==""){
getServletContext().getRequestDispatcher("/form.jsp").forward(request, response);
}
else{
getServletContext().getRequestDispatcher("/welcome.jsp").forward(request, response);
}
%>
 

There are 2 ways to redirect the page
1) Use the forward :- By using this
you will get the all the objects in the redirected page.
2) response.sendRedirect("Path") :- In This case the control is not transferred to the next page.

application javax.servlet.ServletContext config javax.servlet.ServletConfig exception java.lang.Throwable out javax.servlet.jsp.JspWriter page java.lang.Object PageContext javax.servlet.jsp.PageContex...

The web container is a Java runtime environment which is responsible for managing life cycle of JSP pages and Servlets. A web container is responsible for instantiating, initializing and invoking Serv...

Containers are like window for Servlet and JSP's to ourside world. As explain by many answers it provides interface to ourside world. Few advantage of deploying JSP and servlet in container is:1) ...

What exactly mean by the following:

jsp-api.jar is missing in the build path.

What happen if it is occurred in Struts 2.1.0 ? while i trying to submit a list value from JSP page in action class : -



why jasper exception occurred when action successfully got the list value - and It give " Unhandled exception in struts : JasperException.

Can someone tell me...how a servlet container execute init(),service() and destroy() method in a sequential manner ?
is it true that a servlet container itself contains a main() method which call these methods ?

thanks in advance...

We can use main method in Jsp/servlet, but there is no use. This main() method will not execute throughout the life cycle. Then why should we need to use.Generally these JSP/Servlets are server side t...

NO, There will be one single instance of the servlet in the web-container ,when request arrives to the server a thread will be created rather creating the object. so that multiple request will have ...

single servlet object will be loaded in memory and one thread per request would be created by the container to serve those requests.

Thanks,
Vinay

JSP is an advanced version of Java Servlets. It will also extends the functionality of a web server. It will give clear separation between application logic and prosentation logic.

Hi, JSP is a server side scripting language. It encapsulates the java code with the html code. It is simpler and easier to develop application with JSP than servlet or any othere.

no. both session retained.

Hi Prasanth, The case is differnt here.Assume you have opened gmail.com and logged in... session will be created.Then you have tried to replace the url as yahoo.com, here the browser will identify the...

request is an implicit object in JSP

We can use thread local variable as an alternative to synchronization.

there is a way to do so, but its a bit complex and has be done by a programmer.Well u can implement the semaphore architecture using the the semaphore variable.this can be done as following:take a boo...