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Behavioral patterns

In software engineering, behavioral design patterns are design patterns that identify common communication patterns between objects and realize these patterns. By doing so, these patterns increase flexibility in carrying out this communication.

  • Chain of responsibility
    A way of passing a request between a chain of objects
  • Command
    Encapsulate a command request as an object
  • Interpreter
    A way to include language elements in a program
  • Iterator
    Sequentially access the elements of a collection
  • Mediator
    Defines simplified communication between classes
  • Memento
    Capture and restore an object's internal state
  • Null Object
    Designed to act as a default value of an object
  • Observer
    A way of notifying change to a number of classes
  • State
    Alter an object's behavior when its state changes
  • Strategy
    Encapsulates an algorithm inside a class
  • Template method
    Defer the exact steps of an algorithm to a subclass
  • Visitor
    Defines a new operation to a class without change

Rules of thumb

Code examples