Servlets are server side Java programs that are designed to enhance the capabilities of a server. Servlets are not tied with a specific client-server protocol but they are widely used with HTTP and the word "Servlet" commonly refers to "HTTP Servlet".
Packages javax.servlet (the basic Servlet framework) and javax.servlet.http
extends the Standard Java classes. Servlets are portable in nature because they are written in the highly portable Java language and follow a standard framework. Servlets are used to create sophisticated server extensions in a server and operating system independent way.
Following are the uses of HTTP Servlets:
· Processes and/or stores the data submitted by an HTML form.
· Provides dynamic content, e.g. returns the results of a database query to the client.
· Manages state information on top of the stateless HTTP, e.g. an online shopping cart system that manages shopping carts for many concurrent requests and maps every request to the right customer.
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