CDI vs Spring: What are the differences?

Key Differences between CDI and Spring

CDI (Contexts and Dependency Injection) and Spring are both frameworks used for dependency injection in Java applications. While they have similarities in terms of managing dependencies, there are several key differences between the two.

1. Configuration and XML Usage: CDI relies on annotations for configuration, allowing for type-safe usage and reducing the need for XML files. In contrast, Spring heavily uses XML files for configuration, providing more flexibility but also increasing the complexity of the configuration process.

2. Scope Management: CDI provides a wider range of bean scopes, including built-in support for conversation, application, and request scopes. Spring, on the other hand, mainly focuses on Singleton and Prototype scopes, with other scopes available through third-party libraries.

3. Integration: Spring is a more comprehensive framework that offers various modules for different purposes like security, web development, and data access. CDI, on the other hand, is primarily focused on dependency injection and does not provide the same level of integration capabilities as Spring.

4. Transaction Management: Spring provides declarative transaction management using annotations or XML configuration. CDI, on the other hand, does not include built-in transaction management and relies on integration with other frameworks like Java Transaction API (JTA).

5. Aspect-Oriented Programming: Spring has extensive support for Aspect-Oriented Programming (AOP), allowing developers to separate cross-cutting concerns from the main business logic. CDI does not have native support for AOP, and developers need to rely on external libraries or frameworks for AOP functionalities.

6. Enterprise Capabilities: Spring is well-known for its comprehensive enterprise features, including advanced security configurations, batch processing, and enterprise integration patterns. CDI, although it provides CDI extensions for certain enterprise capabilities, does not offer the same extensive set of enterprise features as Spring.

In summary, while both CDI and Spring are dependency injection frameworks, they differ in terms of configuration, scope management, integration capabilities, transaction management, aspect-oriented programming support, and enterprise features.