Behavioral patterns are those patterns that are most specifically concerned with communication between objects. In this chapter, we’ll see that: (Each chapter is in PDF format)

• The Observer pattern defines the way a number of classes can be notified of a change,
• The Mediator defines how communication between classes can be simplified by using another class to keep all classes from having to know about each other.
• The Chain of Responsibility allows an even further decoupling between classes, by passing a request between classes until it is recognized.
• The Template pattern provides an abstract definition of an algorithm, and
• The Interpreter provides a definition of how to include language elements in a program.
• The Strategy pattern encapsulates an algorithm inside a class,
• The Visitor pattern adds function to a class,
• The State pattern provides a memory for a class’s instance variables.
• The Command pattern provides a simple way to separate execution of a command from the interface environment that produced it, and
• The Iterator pattern formalizes the way we move through a list of data within a class.