Description:

The State pattern allows an object to alter its behavior when its internal state changes

Benefits:

• Localizes state-specific behavior and partitions behavior for different states
• Makes state transitions explicit

When to use:

• An object’s behavior depends on its state, and it must change its behavior at run-time depending on that state.
• Operations have large, multipart conditional statements thatdepend on the object’s state.

Diagram: