Concept of Dependency Injection in Spring

Dependency Injection is a design pattern in which the objects are provided with their dependencies rather than creating them internally. In the context of Spring framework, Dependency Injection allows you to decouple your code and manage dependencies outside of the class, typically through configuration files.

How Dependency Injection is Used in Spring

Dependency Injection in Spring is implemented through Inversion of Control (IoC) containers. These containers are responsible for instantiating objects, configuring them, and managing their dependencies. By using annotations or XML configurations, you can tell the container which dependencies to inject where.

For example, in Spring, you can use annotations like @Autowired or @Resource to inject dependencies into your beans. This allows for a more flexible and testable codebase, as you can easily swap out dependencies or mock them for testing purposes.

Overall, Dependency Injection in Spring simplifies the process of managing dependencies in your application and promotes modularity, scalability, and maintainability of your codebase.