The Servlet API is a comprehensive set of functions which provides all the functions required for complex interactions between a Web client and a Web container, including session management, security, dispatching requests, and more.
All the servlet classes and interfaces are organized into the following packages:
javax.servlet— Provides all the base interfaces needed for implementing generic servlets and HTTP servlets
javax.servlet.http— Provides all the base interfaces and classes needed for implementing an HTTP servlet
In the following sections, we'll look at the important interfaces and classes that make up the servlet implementation, along with examples for each of the operations.
The Servlet Interface