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Discussion About Dispatcher Servlet in Java?

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What is Dispatcher Servlet?

Spring's web MVC framework is, like many other web MVC frameworks, request-driven, designed around a central servlet that dispatches requests to controllers and offers other functionality that facilitates the development of web applications. 

Spring's DispatcherServlet however, does more than just that. It is completely integrated with the Spring IoC container and as such allows you to use every other feature that Spring has.

The request processing workflow of the Spring Web MVC DispatcherServlet is illustrated in the following diagram. The pattern-savvy reader will recognize that the DispatcherServlet is an expression of the “Front Controller” design pattern 

Front controller is a typical design pattern in the web applications development. In this case, a single servlet receives all requests and transfers them to to all other components of the application. The task of the DispatcherServlet is to send request to the specific Spring MVC controller.

Example:

<servlet-mapping>
    <servlet-name>dispatcher</servlet-name>
    <url-pattern>/*</url-pattern>
</servlet-mapping>

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posted Feb 26 by anonymous

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