1. What to know for the exam

2. Smalltalk will be used for questions, but there will not be questions about the grammar. Questions might ask – how particular patterns are different for Smalltalk – How to program a pattern in Smalltalk – How to program basic OO problem – questions that assume general knowledge of basic classes like collections or streams

3. Kent Beck patterns Composed method Complete creation method Conversion method Query method Intention revealing message Double dispatch

4. Core patterns Mediator Façade Proxy Command Template Method Adapter Null Object Composite Strategy Decorator State Iterator Observer Value Object

5. Creational Abstract factory (peripheral) Factory method Prototype Builder Singleton Dependency Injection

6. Peripheral Memento Chain of responsibility Bridge Visitor Type Object Extension Object Generation Gap

7. Compound Flyweight – To save space, factor out a Value Object, and create them using a Memoizing Factory that records the flyweight pool. Interpreter – Represent a program with a Composite, and let the class hierarchy match the grammar of the language. Define an “ interpret ” method in each class.

8. Dangerous Patterns Mediator – Supposed to be used to allow colleagues to be reusable. Is often used to allow programmers to continue to be procedural. Singleton – Supposed to be used to encapsulate global state when it cannot be eliminated. Is often used as a justification of global state.

9. Principles Single responsibility principle Open/closed principle Liskov substitution principle Dependency inversion principle