Apache Struts
Apache Struts is an open-source web application framework for developing Java EE web applications. It follows the Model-View-Controller (MVC) architectural pattern, providing a structured approach to building scalable and maintainable web apps. It extends the Java Servlet API to encourage developers to adopt a model-based architecture.
Developers should learn Apache Struts when building enterprise-level Java web applications that require a robust MVC framework for separation of concerns and easier maintenance. It's particularly useful in legacy systems or environments where Struts is already established, offering features like form validation, internationalization, and tag libraries. However, it's less recommended for new projects due to security vulnerabilities and the availability of modern alternatives.