What is the difference between the Struts framework and Spring MVC?

The Struts framework and Spring MVC framework are two commonly used Java web development frameworks, and they have some differences in design principles and usage methods, as outlined below:

1. Design concept: Struts is a framework based on the MVC (Model-View-Controller) design pattern, emphasizing the separation of different responsibilities in an application. On the other hand, Spring MVC is an MVC implementation based on the Spring framework, placing more emphasis on decoupling and flexibility.
2. Spring MVC framework utilizes Spring’s Inversion of Control (IoC) and Dependency Injection (DI) mechanisms to easily manage object lifecycles and dependencies, whereas Struts framework lacks these functionalities and requires manual management of object creation and dependencies.
3. Configuration process: Struts framework employs XML files to configure request handlers and view resolvers, which can be relatively cumbersome. On the other hand, Spring MVC utilizes annotations and Java configuration classes to configure request handlers, view resolvers, among other components, making the configuration more concise and flexible.
4. Testing: Due to the use of inversion of control and dependency injection mechanisms in the Spring MVC framework, it is easier to conduct unit and integration tests. In contrast, the Struts framework requires manually creating objects and simulating requests, making testing relatively more complex.
5. Ecosystem: The Spring framework is a large ecosystem with abundant third-party libraries and plugin support. As part of Spring, Spring MVC can easily integrate with other Spring components. In contrast, the ecosystem of the Struts framework is relatively small, with limited support for plugins and extensions.

In conclusion, the Struts framework emphasizes MVC architecture and standardized request processing, making it suitable for traditional enterprise web application development. On the other hand, the Spring MVC framework focuses on decoupling and flexibility, making it suitable for large, complex application development and easy integration with other Spring components. The choice of which framework to use should be based on specific project requirements and the preferences of the development team.