The State Pattern allows an object to alter its behavior when its internal state changes, making the object appear to change its class.
- Context: Maintains an instance of a ConcreteState that defines the current behavior.
- State: Declares an interface for encapsulating behavior associated with a particular state of the context.
- ConcreteState: Implements behavior specific to the state.
- Managing the state of a document as it's drafted, reviewed, and published.
- Finite state machines like in vending machines or turnstiles.
- Localizes state-specific behavior.
- Simplifies the logic for state transitions.
- Encourages cohesion by keeping state-related behavior in one place.
