Behavioral patterns

Memento

Capture an object's internal state into an opaque snapshot you can stash away and restore later, implementing undo without breaking encapsulation. An animated lesson where the diagram draws itself as the design grows.

  • Lesson 9 of 10
  • Animated diagrams
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Behavioral patterns

  1. 1Strategy
  2. 2Observer
  3. 3State
  4. 4Command
  5. 5Chain of Responsibility
  6. 6Template Method
  7. 7Iterator
  8. 8Mediator
  9. 9Memento
  10. 10Visitor
10 lessons, each with diagrams that draw themselves.

What you will learn

  • The idea: a snapshot you can put back
  • An analogy: save points in a game
  • The three roles
  • Why encapsulation survives
  • Versus Command-based undo
  • The cost of snapshots

More low-level design

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Sign in and the lesson opens with its diagram ready to play, and the rest of Behavioral patterns beside it.

Sign in to open itSee plans

DSA comes with the all labs plan and every ChaiCode batch.