Apache Struts vs Vaadin: What are the differences?

# Introduction

Apache Struts and Vaadin are both popular frameworks used in Java web development. While they serve the same purpose of facilitating web application development, there are key differences between the two that developers need to understand.

1. **Architecture**: Apache Struts follows a Model-View-Controller (MVC) architecture, where the controller handles the incoming requests, processes them, and then delegates the response to the view for rendering. In contrast, Vaadin utilizes a component-based architecture, where the entire UI is built as a tree of components. This makes Vaadin more suited for single-page applications.
   
2. **Client-Side Rendering**: Apache Struts generates HTML on the server-side and sends it to the client, while Vaadin performs client-side rendering. Vaadin communicates with the server using AJAX calls to update the UI, providing a more dynamic and responsive user experience.
   
3. **Learning Curve**: Apache Struts requires a good understanding of MVC concepts and configuration through XML files, which can be challenging for beginners. On the other hand, Vaadin abstracts away the complexities of web development by providing a higher-level API and a more intuitive development experience, making it easier for new developers to get started.

4. **Component Library**: Vaadin comes with a rich set of pre-built UI components that offer a more consistent look and feel out of the box. In contrast, Apache Struts relies on third-party libraries for UI components, which may lead to inconsistencies in design and functionality across the application.

5. **Community Support**: Apache Struts has been around longer and has a larger community compared to Vaadin. This means that developers using Apache Struts can find more resources, tutorials, and support online. However, Vaadin has been gaining popularity in recent years, with an active community and growing ecosystem.

6. **Flexibility in UI Development**: Vaadin allows for a more flexible and interactive UI development experience by enabling developers to create custom components and layouts easily. In comparison, Apache Struts may require more manual coding for complex UI designs and interactions.

In Summary, Apache Struts and Vaadin differ in their architecture, client-side rendering approach, learning curve, component library, community support, and flexibility in UI development.