In the design of

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Web application A web application (or web app) is application software that is accessed using a web browser. Web applications are delivered on the World Wide Web to users with an active network connection. History In earlier computing models like client-serv ...

s, there are two commonly used design models, referred to as Model 1 and Model 2.JavaServer Pages - Specification 0.92. JavaServer Pages Access Model. October 7, 1998
/ref> Model 1

In Model 1, a request is made to a JSP or

servlet A Jakarta Servlet (formerly Java Servlet) is a Java software component that extends the capabilities of a server. Although servlets can respond to many types of requests, they most commonly implement web containers for hosting web application ...

and then that JSP or servlet handles all responsibilities for the request, including processing the request, validating data, handling the business logic, and generating a response. The Model 1 architecture is commonly used in smaller, simple task applications due to its ease of development. Although conceptually simple, this architecture is not conducive to large-scale application development because, inevitably, a great deal of functionality is duplicated in each JSP. Also, the Model 1 architecture unnecessarily ties together the business logic and presentation logic of the application. Combining business logic with presentation logic makes it hard to introduce a new 'view' or access point in an application. For example, in addition to an

HTML The HyperText Markup Language or HTML is the standard markup language for documents designed to be displayed in a web browser. It can be assisted by technologies such as Cascading Style Sheets (CSS) and scripting languages such as JavaSc ...

interface, you might want to include a

Wireless Markup Language Wireless Markup Language (WML), based on XML, is a now-obsolete markup language intended for devices that implement the Wireless Application Protocol (WAP) specification, such as mobile phones. It provides navigational support, data input, hyp ...

(WML) interface for wireless access. In this case, using Model 1 will unnecessarily require the duplication of the business logic with each instance of the presentation code.

References

{{Reflist Software design patterns Software architecture