Chapter 5. Behavioral Patterns
In the last chapter we looked at structural patterns that describe ways in which objects can be constructed to ease interaction.
In this chapter we'll take a look at the final, and largest, grouping of GoF patterns: behavioral patterns. These patterns are ones that provide guidance on how objects share data or, from a different perspective, how data flows between objects.
The patterns we'll look at are as follows:
- Chain of responsibility
- Command
- Interpreter
- Iterator
- Mediator
- Memento
- Observer
- State
- Strategy
- Template method
- Visitor
Once again there are a number of more recently identified patterns that could well be classified as behavioral patterns. We'll defer looking at those until a later chapter, instead keeping to the GoF patterns.
Chain of responsibility
We can think of a function call on an object as sending that object a message. Indeed this message passing mentality is one that dates back to the days of Smalltalk. The chain of responsibility...
