State Pattern

Definitions

1. A behavioral design pattern in which an object delegates behavior to interchangeable state objects, each representing a distinct state, so that the object appears to change its class when its internal state changes — eliminating large conditional blocks.

   In plain English: A design technique where an object behaves differently depending on what state it's in, by swapping out the piece of code that handles the behavior.

   Example: "We replaced the giant switch statement in the order class with the state pattern — now Draft, Submitted, and Shipped are each their own class."

Related Terms

• Mediator Pattern
• Null Object Pattern
• Open-Closed Principle
• Prototype Pattern
• Proxy Pattern
• Software Design
• Structural Pattern
• Template Method Pattern
• Utility Class
• Value Object
• Visitor Pattern