Can you explain the essence of the singleton pattern in the context of Spring and its application?

The singleton pattern in the context of Spring means that the Spring container creates and manages a single instance of a bean for the entire application lifecycle. This prevents the creation of multiple objects of the same class and provides centralized access to it.

By default, the scope of a bean in Spring is singleton. Example:

@Component
public class MyService {
    // service logic
}

In this case, Spring will create one instance of MyService and use it everywhere this bean is required.

This approach is convenient for stateless services that depend on configuration and should be shared across the entire application.