Differentiate between Struts 1 and Struts 2.
Struts 1 and Struts 2 are both frameworks for building web applications in Java, but they have significant differences in architecture, design principles, and features. Here’s a comparison of the two:
Struts 1: Based on the Model-View-Controller (MVC) design pattern, Struts 1 uses a centralized controller (ActionServlet) to handle requests and responses. It relies heavily on XML configuration files (like struts-config.xml) to define actions, form beans, and navigation rules.
Struts 2: Also follows the MVC pattern but has a more flexible architecture. It uses a filter-based approach (ActionFilter) instead of a servlet-based controller. Struts 2 integrates with the Spring framework and supports dependency injection, making it more modular and easier to test.
Struts 1: Configuration is primarily done through XML files, which can become cumbersome as the application grows. The configuration is static and requires redeployment for changes.
Struts 2: Uses annotations for configuration, which reduces the need for extensive XML files. This allows for more dynamic configuration and easier maintenance.
Struts 1: Action classes must extend the Action class and implement a specific method signature. They are tightly coupled with the framework.
Struts 2: Action classes are POJOs (Plain Old Java Objects) and do not need to extend any specific class. This makes them easier to create and test, as they can be used independently of the framework.
Struts 1: Uses ActionForm classes to handle form data, which requires additional boilerplate code for validation and data binding.
Struts 2: Uses a more straightforward approach with automatic population of action properties from request parameters. It also supports built-in validation and type conversion.
Struts 1: Provides a set of custom JSP tags for form handling and other functionalities, but they can be limited and less flexible.
Struts 2: Offers a more powerful and flexible tag library, including support for AJAX and other modern web technologies. It also allows for the use of other tag libraries like JSTL.
Struts 1: Lacks a built-in interceptor mechanism, which means cross-cutting concerns (like logging, authentication, etc.) need to be handled manually.
Struts 2: Introduces interceptors, which allow for reusable code to be applied to multiple actions. This makes it easier to manage cross-cutting concerns.
Struts 1: Error handling is done through the ActionErrors class, which can be cumbersome and requires additional setup.
Struts 2: Provides a more straightforward error handling mechanism, allowing for easier management of validation errors and messages.
Struts 1: Has been largely deprecated and is no longer actively maintained, with many developers moving to newer frameworks.
Struts 2: Continues to be actively developed and supported, with a larger community and more modern features.
In summary, Struts 2 is a more modern and flexible framework compared to Struts 1, offering improved configuration, easier action handling, and better support for contemporary web development practices. If starting a new project, Struts 2 or other modern frameworks (like Spring MVC) are generally recommended over Struts 1.