singletonscoped

Singletonscoped refers to a binding in a dependency injection system that is instantiated once per container lifetime and shared throughout the application. With singleton scope, the container creates a single instance of the component and reuses it for all requests for that type.

Lifecycle and thread safety: The instance typically remains active for the life of the container; initialization can be eager or lazy. Because the same object can be accessed concurrently by multiple threads or execution paths, code inside a singleton should be thread-safe or designed to avoid mutable shared state.

Advantages and drawbacks: Benefits include reduced creation cost, consistent state, and straightforward cross-cutting concerns. Drawbacks include potential for hidden dependencies, difficulty in testing due to global-like state, and risk of memory leaks if not cleared appropriately.

Comparison and configuration: Singleton scope contrasts with per-request or per-injection scopes that create new instances for each use. Many frameworks treat singleton as the default scope or offer explicit configuration to enable it. In some ecosystems it is achieved by a global service registration, a root-level provider, or an application-wide singleton component.

Usage guidance: Use singleton scope for stateless services, shared utilities, or caches that are safe to share. Avoid keeping large amounts of mutable state unless properly synchronized. Consider alternatives like per-request scope for data tied to a single operation, or lightweight stateless services when possible.