Top Most Servlets Faqs

1) What is the servlet?
ANSWER : Servlets are modules that extend request/response-oriented servers, such as Java-enabled web servers. For example, a servlet might be responsible for taking data in an HTML order-entry form and applying the business logic used to update a company's order database.
Servlets are to servers what applets are to browsers. Unlike applets, however, servlets have no graphical user interface.
2) Whats the advantages using servlets than using CGI?
ANSWER : Servlets provide a way to generate dynamic documents that is both easier to write and faster to run. Servlets also address the problem of doing server-side programming with platform-specific APIs: they are developed with the Java Servlet API, a standard Java extension.
3) What are the uses of Servlets?
ANSWER : A servlet can handle multiple requests concurrently, and can synchronize requests. This allows servlets to support systems such as on-line conferencing.
Servlets can forward requests to other servers and servlets.Thus servlets can be used to balance load among several servers that mirror the same content, and to partition a single logical service over several servers, according to task type or organizational boundaries.
4) Which pakage provides interfaces and classes for writing servlets?
ANSWER : javax
5) Whats the Servlet Interfcae?
ANSWER : 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 provide some or all of these methods when developing a servlet.
6) When a servlet accepts a call from a client, it receives two objects- What are they?
ANSWER : ServeltRequest: Which encapsulates the communication from the client to the server.
ServletResponse: Whcih encapsulates the communication from the servlet back to the client.
ServletRequest and ServletResponse are interfaces defined by the javax.servlet package.
7) What information that the ServletRequest interface allows the servlet access to?
ANSWER : Information such as the names of the parameters passed in by the client, the protocol (scheme) being used by the client, and the names of the remote host that made the request and the server that received it.
The input stream, ServletInputStream.Servlets use the input stream to get data from clients that use application protocols such as the HTTP POST and PUT methods.
8) What information that the ServletResponse interface gives the servlet methods for replying to the client?
ANSWER : It Allows the servlet to set the content length and MIME type of the reply.
Provides an output stream, ServletOutputStream and a Writer through which the servlet can send the reply data.
9) What is the servlet Lifecycle?
ANSWER : 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)
10) How HTTP Servlet handles client requests?
ANSWER : An HTTP Servlet handles client requests through its service method. The service method supports standard HTTP client requests by dispatching each request to a method designed to handle that request.




How do u deal property files in servlet?
What methods do u use in Servlet - Applet communication ?
What are the types of Servlet ?
Difference between HttpServlet and Generic Servlets ?
Difference between doGet and doPost ?
What are the methods in HttpServlet?
What are the types of SessionTracking?
What is Cookie ? Why is Cookie used ?
If my browser does not support Cookie,and my server sends a cookie instance What will happen ?
Why do u use Session Tracking in HttpServlet ?
Can u use javaScript in Servlets ?
What is the capacity the doGet can send to the server ?
What are the type of protocols used in HttpServlet ?
What is meant by a servlet ?
What are the types of servlets ? Explain
What is the different between a Servlet and a CGI?
What is the difference between 2 types of Servlets ?
What is the type of method for sending request from HTTP server ?
What are the exceptions thrown by Servlets ? Why ?
What is the life cycle of a servlet ?
What is meant by cookies ?
What is HTTP Session ?
What is the difference between GET and POST methods ?
How can you run a Servlet Program ?
How to commuincate between an applet and a servlet ?
What is a Servlet-to-Servlet communcation ?
What is Session Tracking ?
What are the security issues in Servlets ?
What is HTTP Tunneling?
How do you load an image in a Servlet ?
What is Servlet Chaining ?
What is URL Rewriting ?
What is context switching ?
How will you pass values from HTML page to the Servlet ?
What is Servlet API used for conneting database ?
In servlets, we are having a web page that is invoking servlets? Username and password ? which is cheks in the database ? Suppose the second page also If we want to verify the same information whethe it will connect to the database or it will be used previous information?
What are virtual functions ?
Write down how will you create a binary Tree ?
What are the traverses in Binary Tree ?
Write a program for recursive Traverse ?
What are session variable in Servlets ?
What is client server computing ?
What is meant by Servelet? What are the parameters of the Service Method ?
What is meant by Session ? Tell me something about HTTPSession Class ?
How do you invoke a Servelt? What is the difference in between DoPost and doGet methods ?
What is the difference in between the HTTPServlet and Generic Servlet?
Expalin their methods ? Tell me their parameter names also Have you used threads in Servelet ?
How do you load an Image in a Servlet ?
Explain Servlet Life cycle?
Why do you go for servlet rather than CGI