Iterator Design Pattern

1. Intent

• Provide a way to access the elements of an aggregate object sequentially without exposing its underlying representation.

• The C++ and Java standard library abstraction that makes it possible to decouple collection classes and algorithms.

• Promote to "full object status" the traversal of a collection

• Polymorphic traversal

2. Problem

Need to "abstract" the traversal of wildly different data structures so that algorithms can be defined that are capable of interfacing with each transparently.