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What is JSP? Differentiate it with servlet. Discuss life cycle of servlet in brief.

 JSP (JavaServer Pages) is a technology used for creating dynamic web pages in Java. JSP allows you to embed Java code directly into HTML pages, making it easy to create dynamic content. JSP pages are compiled into servlets by the web container.


Servlets are Java programs that run on a web server to handle client requests and generate dynamic responses. Servlets can handle any type of request (HTTP, FTP, etc.) and produce any type of response (HTML, XML, etc.). Servlets are often used as the backend processing for web applications.

The main difference between JSP and servlets is that JSP is a technology for creating dynamic web pages, whereas servlets are Java programs for handling HTTP requests and producing responses. Servlets are the underlying technology behind JSP.


The life cycle of a servlet is as follows:

  1. Loading: When the web container starts up or receives a request for a servlet, it loads the servlet class into memory.
  2. Initialization: After the servlet class is loaded, the web container creates an instance of the servlet by calling the init() method. The init() method is called only once in the life cycle of the servlet.
  3. Handling Requests: Once the servlet is initialized, it is ready to handle client requests. The web container creates a new thread for each request and calls the service() method to handle the request. The service() method determines the type of request (GET, POST, etc.) and calls the appropriate method (doGet(), doPost(), etc.) to handle the request.
  4. Unloading: When the web container shuts down or decides that the servlet is no longer needed, it calls the destroy() method to give the servlet a chance to clean up any resources it may be using. The destroy() method is called only once in the life cycle of the servlet.

During the life cycle of a servlet, the init() method is called only once, while the service() method may be called multiple times to handle different requests.

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