Design patterns are intended to solve common design problems. These patterns provide guidelines for solving a design issue, and their techniques are proven to work. There are 23 original patterns, categorized into creational, structural, and behavioral patterns. Different design patterns exist for different types of known design issue. In this chapter, we discussed some commonly-used patterns in enterprise applications.
Design patterns introduce transparency and clarity to the system's design, and provide reusable constructs that help to build a better enterprise system. Selecting a design pattern from the set of patterns is important for solving a design issue that we are trying to solve.
The first thing that we need to do before selecting a pattern is to understand the problem and see whether it is related to object creation, or its behaviors,...