What Is Servlet?


Servlet technology is employed to make an internet application (resides at server side and generates a dynamic web page).

Servlet technology is strong and scalable due to the Java language. Prior to Servlet, CGI (Common Gateway Interface) scripting language was usually a server-side programming language . However, there have been many disadvantages to the present technology. We have talked about these disadvantages below.

There are numerous interfaces and classes inside the Servlet API such as Servlet, GenericServlet, HttpServlet, ServletRequest, ServletResponse, etc.

What is a Servlet?

Servlets are often described in some ways , counting on the context.

  • Servlet may be a technology which is employed to make an internet application.
  • Servlet is an API that gives many holographics and classes together with documentation.
  • Servlet is an interface that has to be executed for generating any Servlet.
  • Servlet may be a class that enlarges the capabilities of the servers and acknowledges the incoming requests. It can answer any appeal.
  • Servlet may be a web component that's deployed on the server to make a dynamic website.

Let’s Have one Q&A:

  • What is the online application and what's the variation between Get and Post request?
  • What knowledge will you acquire by the online server if we appeal for a Servlet?
  • How to start a servlet in Eclipse, MyEclipse and Netbeans IDE?
  • What are the procedures for servlet combination and what's the distinction between RequestDispatcher and sendRedirect() procedure?
  • Differentiate between ServletConfig and ServletContext interface?
  • How many courses of action can we carry on the state of a user? Which perspective is usually utilized in web development?
  • How to count the entire number of tourists and the whole reaction time for an invitation using Filter?
  • How to start and run servlet with annotation?
  • How to generate registration forms by utilizing Servlet and Oracle databases?
  • How can we up-load and downlink the file from the server?

What is an Internet (web) Application?

A web application is an application accessible from online . An internet application consists of web elements like Servlet, JSP, Filter, etc. and further elements such as HTML, CSS, and JavaScript. The online section typically executes in Web Server and answers the HTTP request.

Common Gateway Interface (CGI)

CGI technology enables the online server to call an external program and proceed HTTP appeal figures to the external program to proceed the request. For every request, it starts a replacement process.

Disadvantages of CGI

There are many difficulty in CGI technology:

  • If the amount of clients increases, it takes longer for sending the reply.
  • For each request, it starts a process, and therefore the web server is restricted to start out processes.
  • It makes use of platform dependent on language e.g. C, C++, perl.

Advantages of CGI

There is much supremacy of Servlet over CGI. The online container produces threads for picking up the multiple requests to the Servlet.

Threads have many benefits over the Processes like they share a standard memory area, are lightweight, cost of conveying between the threads are low. the benefits of Servlet are given below:

  • Better performance: because it produces a thread for every request, not operation.
  • Portability: because it makes use of Java language.
  • Robust: JVM manages Servlets, so we do not have to worry with reference to the memory leak, garbage pickup , etc.
  • Secure: because it makes use of java language