Why JSF?

Before JSF existed, most Java web applications were typically developed using non-standard web application frameworks such as Apache Struts, Tapestry, Spring Web MVC, or many others. These frameworks are built on top of the Servlet and JSP
standards, and automate a lot of functionality that needs to be manually coded when using these APIs directly.

Having a wide variety of web application frameworks available, often resulted in “analysis paralysis”, that is, developers often
spend an inordinate amount of time evaluating frameworks for their applications. The introduction of JSF to the Java EE specification resulted in having a standard web application framework available in any Java EE compliant application server.
We don’t mean to imply that other web application frameworks are obsolete or that they shouldn’t be used at all. However, a lot of organizations consider JSF the “safe” choice since it is part of the standard and should be well supported for the foreseeable future. Additionally, NetBeans offers excellent JSF support, making JSF a very attractive choice.
Strictly speaking, JSF is not a web application framework per se, but a component framework. In theory, JSF can be used to write applications that are not web-based, however, in practice JSF is almost always used for this purpose. In addition to being the standard Java EE component framework, one benefit of JSF is that it provides good support for tools vendors, allowing tools such as NetBeans to take advantage of the JSF component model with drag and drop support for components.