Design Pattern

Behavioral Patterns Behavioral patterns are those patterns, which are specifically concerned with communication (interaction) between the objects. The interactions between the objects should be such that they are talking to each other and are still loosely coupled. The loose coupling is the key to n-tier architectures. In this, the implementations and the client should be loosely coupled in order to avoid hard coding and dependencies. 
 

1. Iterator Pattern
   Iterator pattern is the mechanism of accessing all the objects in a collection. To sequentially access the objects of a collection, the iterator pattern defines an interface containing the methods that access the objects of a collection or the aggregate objects without having knowledge about its internal representation. It provides uniform interface to traverse collections of all kinds. Aggregate objects are the objects containing the group of objects as a unit. We can also referred them as container or collection. Hash table and linked list are the examples of aggregate objects.

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