# What is Servlet in Java ?

Servlets are a component of the JEE framework used for web development. Servlet is a class that handles requests, processes them and reply back with a response. Servlets are under the control of another Java application called a ***Servlet Container.*** Servlets need to be registered first so that a container, When an application running in a web server receives a request*,* the Server hands the request to the Servlet Container – which in turn passes it to the target Servlet.

For servlet life cycle including 3 part :

* init()
* service()
* destroy()

**init()**

1. Loads the servlet class
2. Creates an instance of the servlet class
3. Initializes it by calling the *init* method

**service()**

This method is only called after the servlet's *init()* method has completed successfully*.*The Container calls the *service()* method to handle requests coming from the client, interprets the HTTP request type (*GET*, *POST*, *PUT*, *DELETE*, etc.) and calls *doGet*, *doPost*, *doPut*, *doDelete*, etc. methods as appropriate.\
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**destroy()**

Called by the Servlet Container to take the Servlet out of service.This method is only called once all threads within the servlet's *service* method have exited or after a timeout period has passed. After the container calls this method, it will not call the *service* method again on the Servlet.

Reference: <https://www.baeldung.com/intro-to-servlets>