Key Differences Between @Autowired and @Qualifier Annotation

What is Dependency Injection in Spring?

Dependency Injection (DI) is a design pattern used in software development, and it plays a significant role in the Spring Framework, which is a popular framework for building Java-based enterprise applications. Dependency Injection is a technique where one object supplies the dependencies of another object, rather than the dependent object creating them itself. In other words, it’s a way to achieve Inversion of Control (IoC), where the control over the flow of a program’s execution is shifted from the program itself to a framework or container....

How Dependency Injection Works in Spring?

Components: In a Spring application, you typically define various components, such as classes or beans, that represent different parts of your application’s functionality. Dependencies: These components often have dependencies on other components or services to perform their tasks effectively. Configuration: You configure your Spring application using XML-based configuration files, Java annotations, or Java-based configuration classes (using @Configuration and @Bean annotations). Injection: Spring’s IoC container manages the creation of objects and their dependencies. When a component needs a dependency, the container injects it at runtime, ensuring that the required objects are available and correctly initialized....

Dependency Injection with @Autowired

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Key Differences Between @Autowired and @Qualifier Annotation

@Autowired is used to automatically inject dependencies into a class. When you annotate a field, setter method, or constructor with @Autowired, Spring will attempt to find a matching bean in the application context and inject it into the annotated component. It is typically used when you have multiple beans of the same type, and Spring needs to determine which one to inject automatically....

When to use @Autowired and @Qualifier?

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Conclusion

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